Amusing, yes, but perhaps as well not to get too friendly with the Now Show – if I remember correctly, they’ve been none too kind to Al Gore in the past. Mind you, I can’t recall them being kind to anybody in the past.
Just read the transcript and I want to congratulate the folks who put their effort into the global warming debate in New York city. Regardless of the outcome of the vote at the end, you did a fantastic job! Clearly on substance, as one reads the transcripts your “sceptic” crowd said almost nothing about global warming, lots of funny comments but nothing substantial at all. Don’t know how it will sound on NPR yet but on paper, word for word, idea for idea, it was a great effort! And very helpful for someone like myself who took part in Gore’s training in Nashville and am to some extent dealing with the same challenges myself during my own presentations. THANK YOU.
I read the transcript of the debate you participated in. Those formats are useless for getting to the bottom of anything, but there may be a better way – the blogosphere.
Here is Lindzen’s closing statement. Perhaps you would like to rebut:
RICHARD S. LINDZEN Yes. I think it’s a little bit difficult to know how to respond,
to be told that, uh, one shouldn’t attack scientists while you’re attacking scientists,
to go and say you have to control methane without explaining that methane has
stopped growing. You don’t explain why there’s global warming on Mars, Jupiter,
Triton and Pluto. You don’t look at the ocean data and see, that whereas your boss
Jim Hansen was saying that the heating of the ocean proved the flux that he needed
for high sensitivity, that in the last year there’ve been two papers in the same
journal, that point out that the original Levitus data’s wrong, that the ocean is cool,
and that the new numbers would call for one-tenth the sensitivity that Hansen
mentioned. If all this is so certain, why is the data changing, or is it a case when the
data changes you ignore it, and
BRIAN LEHRER One
RICHARD S. LINDZEN stick to the point. [APPLAUSE]
Marcus Brigstocke is good, however he certainly does tend to the left in UK political terms. His aim can be a little wobbly sometimes, see for example his interesting assertion than “global warming is supported by 80% of the world’s scientists” — but of course it’s a five minute angry rant, not a paper in Nature.
Well done the Corduroy King ;)
Incidentally the language is rather more direct than usual – this goes out at 6:30pm on a Friday evening on the main BBC speech radio channel, I’m rather surprised he got “bastard” and “prick” through. Excellent venting of spleen, though, and interesting to hear the background of the producer of this “documentary”.
There was also the “Moral Maze”, Radio 4, on Wednesday 14th March 2007 which discussed GW and included George Monbiot of the Guardian. Sadly the beeb don’t produce downloads for it.
The Moral Maze is broadcast on Radio 4 at 8pm on Wednesdays and repeated on Saturdays at 10.15pm i.e tonight. One of the questioners accused George of sidestepping a certain question three times. Can you help him and me? I’ve forgotten the Q myself.
I’m glad that someone else heard the Now Show. I rarely listen, but was glad I did. Humour and sarcasm have a way of cutting the legs from under ill-considered opinion in a way that common sense and logic often fail to do. Pens v swords. Perhaps something to remember if you go head-to-head in another debate?
If you’re not using a machine that plays streaming audio (or using for example the Lynx text browser, popular for blind people who read using text-to-speech) the radio show is also — for the moment — downloadable as a .MP3 audio file via this link, found at the show’s main page:
Don’t know whether it’s relevant to TGGWS, but the Great British public have this evening voted for a song which appears to be a celebration of air travel as their chosen entry for the Eurovision song contest.
I love the stand-by power bit, it’s so sad; otherwise intelligent people are absolutely wedded to this stand-by, “instant on” thing. And, the irony is that people will search for five or ten minutes for the misplaced remote so they can turn the television on, rather than simply pushing the buttons on the set. I guess they like the “magical” “action at a distance” quality of it….
Probably the only way to really solve the problem is to either do away with standby, (one’s magical remote will still work after one turns the set on), or get the manufacturers to develop much more efficient stand-by modes. I have serious doubts that many people will pull the plugs on their stand-by appliances voluntarily, it’s much too “inconvenient”.
Mike, in the question posed (three times) to George Monbiot what we have is a perfect example of Melanie Phillips’ complete misunderstanding of the precautionary principle aspects of ‘Post Normal Science’ (PNS).
Funtowicz and Ravetz (Futures Sept 1993) pointed out that in order to formulate policies in relation to risk issues “where the facts are uncertain, values are in dispute, stakes are high and decisions urgent” then an “extended peer community” is needed in order to deliberate a policy solution. This is in contrast to the pure-science curiosity-driven approach which promotes reductionism and testing until scientific “truth” is deducted, a replicable test designed and the process peer reviewed.
What Funtowicz and Ravetz suggested is that “Science cannot always provide well founded theories based on experiments for explanation and prediction, but can frequently achieve at best only mathematical models and computer simulations, which are essentially untestable. On the basis of such uncertain inputs, decisions must be made, under conditions of some urgency. Therefore policy cannot proceed on the basis of factual predictions, but on policy forecasts”
In asking the question [as aggressively] as she does Phillips is suggesting that, in her understanding, PNS makes fossil-fuel companies completely justified in their approach of hypothesis formulation and testing i.e. their starting point (H0) is that “fossil fuel use is not a problem” but their testing merely involves searching for anything (absolutely anything) which proves that hypothesis whilst discounting any other evidence, because that’s what they want to do.
In essence pure-science has indicated that there is an interaction between the atmosphere, the sun and increasing CO2 concentrations which causes global temperature to rise. This process cannot, however, be explicitly tested in-situ because of the sheer scale and complexity of the atmospheric system and the irreducible uncertainties introduced by other processes acting within it. What this necessitates is multiple stakeholder (not just by amongst scientists) deliberation about what is known and what is uncertain in order that value commitments can be made over the policies to be enacted which can affect their own welfare as well as that of other stakeholders, including future generations and other species.
In answering the question Monbiot is absolutely correct in asserting that pure-science is still vital to PNS because it introduces urgent issues into the policy domain. Where Phillips couldn’t be more wrong is in her belief that post normalism (as described by Mike Hulme) simply means that climate science is so uncertain that the science can be thrown out with the bath water in order to allow a purely value based decision process to prevail.
The remarkable thing is not that I was attacked. But that the attacks have been so feeble. The ice-core data was the jewel in the global-warming crown, cited again and again as evidence that carbon dioxide ‘drives’ the earth’s climate. In fact, as its advocates have been forced to admit, the ice-core data says the opposite. Temperature change always precedes changes in CO2 by several hundred years. Temperature drives CO2, not the other way round. The global-warmers do not deny this. They cannot.
During the post-war economic boom, while industrial emissions of CO2 went up, the temperature went down (hence the great global-cooling scare in the 1970s). Why? They say maybe the cooling was caused by SO2 (sulphur dioxide) produced by industry. But they say it mumbling under their breath, because they know it makes no sense. Thanks to China and the rest, SO2 levels are far, far higher now than they were back then. Why isn’t it perishing cold?
Too many journalists and scientists have built their careers on the global-warming alarm. Certain newspapers have staked their reputation on it. The death of this theory will be painful and ugly. But it will die. Because it is wrong, wrong, wrong.
Jeez, I answered (as an amateur) the ‘why isn’t it cold from Chinese sulfates just yesterday in another thread (because in 1970 only half the total fossil fuel had been burned, aerosols act fast, CO2 warming happens over decades); now with twice that much fossil fuel burned, we’re well into the warming from the past emissions and the aerosols are just reducing that trend — operating on a very different background than they did in 1940-1970.
Guess whoever asked it was cut’n'pasting, eh? Someone competent, correct my answer please.
By the way, that debate Gavin attended was interesting. It had Crichton, Lindzen and Philip Stott on one side, Gavin, Brenda Ekwurzel and Richard Somerville on the other. The motion was “Global Warming Is Not A Crisis”.
Prior to the debate they polled the audience and found 30-57-13 for-against-don’t know. After the debate it was 46-42-11. The ‘con’ side of the debate, if the numbers are square, took an audience that believed in their case and unconvinced them of it.
I would live to hear Gavin’s thoughts on this.
If this means that sound science loses the sound-byte war because it takes too long to explain it, then there is probably going to be a nagging problem communicating this sort of nuance to the public.
“During the post-war economic boom, while industrial emissions of CO2 went up, the temperature went down (hence the great global-cooling scare in the 1970s). Why? They say maybe the cooling was caused by SO2 (sulphur dioxide) produced by industry. But they say it mumbling under their breath, because they know it makes no sense. Thanks to China and the rest, SO2 levels are far, far higher now than they were back then. Why isn’t it perishing cold?”
Because sulfur dioxide emissions are going down and CO2 levels are going up would be my guess.
The CO2/temperature ice core lag is dealt with elsewhere on RC- but let’s take Durkin’s statement on global SO2 emissions to task. China’s emissions in 2006 were equal to the USA’s 1980 emissions at around 25.5Mt. In 1970 USA emissions were around 31Mt. The USA has now reduced emissions by @ 50% since 1970. Does anyone have more data on global SO2 emissions? With the collapse of the Soviet economy and severe SO2 reductions in W. Europe because of environmental legislation I suspect global SO2 emissions are lower now than during the 1970′s.
Funny how everyone seems to be concenreating on climate change here in th UK when politically we are well on the way doing something about it and most Britons seem convinced that something needs to be done, well enough Britons to start the three main parties vying for votes by offering policies anyway and the EU has a even wider climate science remit.
The issue is the United States where only states seem to be doing anything, the country as a whole seems hell bent on burning more fossil fuels than ever with the plans to build 159 new coal fired power plants over the next decade and the technology to sequester it is just a prototype at the moment, nice.
I have just read a peice in the Daily Telegraph concerning this man, Prof Nigel Weiss, from the department of astrophysics at Cambridge University. He is an astrophysicist there and he is claiming to have been misrepresented in the following peice which seems to be stating that CO2 may not be the sole cause of climate change that is relevant to our current warming, the Sun might be assisting us also.
It looks like what he is saying is that the Sun is going through its lower polar magnetic field moment in 50 years.
I wonder if real climate could resolve the solar issue once and for all if possible by contacting these solar and astro physicists and asking them for their expert opinion on why all of a sudden the Sun is becomming the tour de force of climate change?
It all seems plausable even if these people have beem misquoted.
Re: #22 (off-topic) Pete, isn’t that 3-4 times you make the same point? Some progress re this concern:
US legislative bodies are presently deliberating bills to (1) amend Clean Air Act to regulate emission of greenhouse gases from electric utilities; (2) accelerate reduction of US greenhouse gas emissions; (3) green capitol buildings to lead US by example, and so on. Not end results, but activity that merits awareness.
Some scientists in the UK seem to have decided Durkin didn’t do a good enough job and the anti-AGW brigade could do with their help, too. It seems they’ve accused the American Association for the Advancement of Science of the “Hollywoodisation” of climate science.
Doesn’t look very contentious, although one might wonder why they only mention Kilimanjaro and ignore all the other glaciers. They seem to imply none of them are retreating due to AGW. And does the term “tipping point” really have “no scientific definition”? I thought scientists objected to its misuse , not to not using it at all. Maybe I’ve got that wrong.
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Perhaps someone should ring them up about the glaciers and in passing ask them who’s idea it was to use the word “Hollywoodisation”.
Lord Taverne, who Chairs Sense about Science, is not known for championing climate science, and has some interesting friends.
Wow, Durkin has a lot of gall. I hope the UK audience that reads his remarks has also seen the program. It actually hurts the skeptics’ side, not helps.
Prof. Wunsch’s inclusion is something I spotted as new, which is why I ended up on RC, reading about The Great Global Warming Sandbagging.
Durkin should be honest: It runs through some of the standard skeptic fare, then quickly descends into the conspiracy theory that AGW is a weapon that is the creation of Maggie Thatcher in her war against the coalworkers union. It then ends with an emotional piece about poverty in Africa.
> A leading solar expert has told how he was vilified by environmental campaigners and condemned
> by scientists after he was wrongly branded a climate-change denier.
> Larry Solomon, the columnist who wrote the profile of Prof Weiss, said: ‘I wrote the piece as a
> laudable profile of Prof Weiss and his work. I am perplexed as to why he has responded in this way.’
Solomon who doesn’t know the meaning of the word “laudable” — unless he’s congratulating himself on the excellence of his own writing there.
I would certainly like to see an investigation of the IP addresses of the “environmental campaigners” who attacked Dr. Weiss — I’d bet on sock puppets pretending to be environmentalists, behind such actions. And whether they’re RCP-types or naive #$&@ [edited], either way, they ought to come to light.
Anecdote, from experience: during the 1960s anti-war protests in the USA, a fair number of us who were more interested in first aid and crowd control than in any rhetoric would go to demonstrations to stand _behind_ the audience and _behind_ the speakers, looking away from them, watching out for the yahoos who would come up and try throwing rocks and bottles over the pacifists to provoke the police. As far as I heard at the time, those yahoos were usually RCP types. Provoking violence by pretending to be on _all_ sides of any debate, to stir up trouble and misunderstanding, is a political tactic.
Don’t fall for this #*$&[edited]. It works quite well:
pretend attack, provoke attack, bogus attack, profit for those who benefit from the confusion.
Yes, there are #%$* [edited] who call themselves ‘environmentalists’ (ask them about ecology — they think it means green stuff out past the suburbs, rather than a science with great uncertainty).
But I think it’s really, really important to validate who’s who when attacks start happening.
Perhaps time for digital signatures, in fact, to know people are who they claim to be.
Indeed the USA are considering bills and acts to do something about it, however considering that 50% of US electricity is coal based and as clean coal technologies do not exist yet to fit to these 159 power stations so what does the USA do? Well I would imagine that they are harrdly going to leave themselves at an economic disadvantage are they and hence I doubt that any of these bill and acts come to anything anytime soon.
What technology presently can replace coal or sequester its exhaust?
Maybe just another instance of scientists taking too little care when talking to the press.
However, I do wonder at the complacency of people sitting in the beautiful, but rarified atmosphere of an Oxford college, with food and drink on tap, and for whom the word drought means little more than not being able to water the front garden, criticizing those who see AGW as a threat to society. It may not seem much of a threat amongst the dreaming spires, but I daresay it looks it bit different if you are living in one of those places in the world where daily life is already a desparate struggle for survival. For these people catastrophe really doesn’t sound too strong a word. And you don’t need to be talking about catastrophic climate change either.
Climate change isn’t some abstract concept , it happens in the real world, interacting with existing circumstances. We can’t deal with the mess we’ve got now, how on earth does anyone think we’re going to cope if it gets worse.
If saying that makes you guilty of “Hollywoodisation”, then I really am living on a different planet.
Just to point out another (and more serious!) rebuttal of TGGWS in this narrated Powerpoint presentation by Christopher Merchant, which nicely points out some of the main errors and logical fallacies.
He does make an error on the solar-T curve, though it’s an understandable one given that the graph is misattributed and mislabelled (and he’s presumably not aware of the Friis-Christensen stuff). The “solar” curve is actually solar cycle length rather than sunspot number, and is dealt with here. His point about selective presentation of the pre-1980 data still stands though.
Marcus Brigstoke said what should have been said by every scientist this week on radio 4 when asked about the programme. Instead we got Sir John Houghton (having written a very good (bad)review of the whole thing http://www.jri.org.uk/index.php?option=com_content&task=view&id=137&Itemid=83
totally fluffed it when asked to name one thing wrong with it. It could be argued that he was just overwhelmed by the ‘target-rich environment’ that question opened up, but frankly he just waffled.
I’ve posted about Hardakers own particular brand of stupidity when interviewed on Friday 17th on another thread (but you should be able to listen to the interview on the BBC’s radio 4 web page – truely a horrible experience), but it shows that some are buying into the idea that the seriousness of AGW is something that should be dabated as some sort of ‘philosphy of science’ question, suitable for high table. Unfortunately, the BBC led with it for the whole morning (Today is the headline leading programme in the UK for news and politics, so if its top of their news, its the top of everyone else’s as well).
The media does not do nuance, it does not do ‘are we absolutely sure?’ and it does not do scientific uncertainity at all well. Whereas the deniers will say something cannot be happening, academics feel much more comfortable with ‘maybe and ‘possibly’. It’s fine when you write it in an article or paper, because we all understand the rules. But when you do it on the Today programme, when you have three minutes before the sport opposite someone who really does not care about truth, its fatal. A large number of people believed that programme (just look at C4, the BBC, the Times and the Guardian’s message-boards), and waffling or welcoming a non-existant ‘debate’ will simply convince them that Stott, Chrichton and co have as much weight as the vast number of scientists actually working on AGW .
But its not just Collier and Hardaker who seem to be sipping the KoolAid. Michael Hulme of the Tyndall Centre seems to also being on this particular track. Back in Feb., he wrote a piece about the media reaction to the IPCC report relase saying pretty much the same thing http://sciencepolicy.colorado.edu/prometheus/archives/climate_change/001117mike_hulme_in_nature.html
, which got a response from the Guardians Science editor that
‘Mike accuses us of “appealling to fear to generate a sense of urgency”
Guilty as charged. Is it not frightening? Is it not urgent?’.
About a month ago, he featured heavily in a rather weak programme on Radio 4 called ‘The Interregation’, which was supposed to take a hard look at Stern and the IPCC report. It was the same line. The programme failed to deliver, relying on nitpicking and the possibility that things might not be as bad in the future as Stern warns. Without his imput, it would have been a very thin programme indeed. He was at it agin this week, with a widely read article saying much the same thing http://environment.guardian.co.uk/climatechange/story/0,,2032821,00.html. He actually managed to give Singers new book a plug of sorts in the second paragraph (he does say its wrong in the eighth, but its a bit late by then), and seems to follow a similar path to Collier and Hardaker.
Indeed, according to this article in the Observer http://environment.guardian.co.uk/climatechange/story/0,,2036762,00.html he’s joined forces with them. Its true that the media does spin stories, but is there any real evidence that climate scientists have actually made the effects of climate change more dramatic? If anything, they may have underplayed the effects. Bill McKibben and New Scientist has both noted that the IPCC is rather conservative, and the 4th report will probably not include the latest and most alarming data.
This breast-beating does nothing to help convince the public that scientists are speaking with one voice on climate change, and will undoubtably do a great deal of damage. Since its taken the British media a great deal of time to cover it in the first place http://www.bjr.org.uk/data/2007/no1_andreadis_smith.htm, why can the scientist involved refrain from giving such mixed signals.
Frankly, if the Royal Society and others does not get its act together, it will be left to george Monbiot and one or two others to fight against the deniers. He’s a zoology trained journalist, but he’s not a climate scientist and ultimately its not his job to do this alone. There should be a real effort to get out the message to the public, a message that should be simple and unambigous.
I’ve tried very hard to get to some facts about GW but find it increasingly difficult. It all seems to boil down to ‘our scientific group is bigger and has better credentials than yours’ or ‘their information may have been funded by an oil company’.
All this seems little better than ‘my dad’s bigger than yours’ and frankly, what does it matter if research is funded by an oil company. The evidence it finds can be tested on it’s own merit. Who paid for it shouldn’t make any difference to any facts – unless of course this whole GW area doesn’t actually have any hard facts.
I watched the program and read the rebutals but still cannot for the life of me understand if CO2 levels lag behind the temperature by 800 years how CO2 causes the temperature to change. You can invoke all kinds of linked feedback mechanisms plus an ‘unknown’ reason why the temperature intially kicked off but surely the simplest possibility is that CO2 does not effect the temperature as much as temperature effects the CO2.
If 1000′s of scientist are so sure then why cant we just have a straight answer on this – please.
The reaction to this single program strikes me as a case of the ‘lady doth protest too much’
Re #32: PhilC — In the ice core records, temperatures rise and this causes carbon dioxide to rise. In the twentieth and twenty-first centuries, carbon dioxide rises (due to burning carbon) and this causes temperatures to rise.
It is a matter of the temperature and the carbon dioxide in the air being out-of-balance. Try reading Wikipedia about greenhose gases.
Comment by David B. Benson — 18 Mar 2007 @ 6:46 PM
re 32 and #33. re does CO2 cause temp rise?
Someone please correct me…but I understand that this is a complete red herring and is NOT what is in the peer reviewed literature…and Lindzen DOES NOT CONTRIBUTE PEER_REVIEWED LITERATURE THAT STANDS UP UNDER SCRUTINY… he is a quack and a charliton.
The correct order is a three step process (from EPICA ice cores as well as three other ice core records).
First, the average Earth’s temps first go up a little. Second, there is a huge CO2 increase as the oceans get warmer/permafrost starts melting, methane starts increasing due to more swamps and the ice age winds stop/slow down (no feeding the hungry little plankton)…and thirdly 600-1000 years later there is a huge temperature increase over the next several thousand years….this is driven largely by the positive CO2 feedback…ie. in effect CO2 causes temperature to rise because it is a feedback.
[I wonder if real climate could resolve the solar issue once and for all if possible by contacting these solar and astro physicists and asking them for their expert opinion on why all of a sudden the Sun is becomming the tour de force of climate change?]
Me too but I think most of the RC posters have already concluded the Sun is a minor player in the recent warming.
We are now with 15-20 years of the end of the 90 year cycle of increased solar output and magnetic activity. Unforunately, our best records of solar output, and hence our understanding of solar output, date only from the middle of cycle. During this same period humans have dumped huge quantities of CO2 into the atmosphere. This creates a muddled picture since both solar activity and CO2 have been increasing at the same time. Both sides would agree that increased CO2 and increased solar activity would increase warming but they differ in the degree of influence they assign to each.
The fact that the current cycle of increased solar activity is nearing its end may be pretty well confirmed:
Phil C (#32):
The lag you mention is observed in the ice core data for past warmings (from glacial to inter-glacial temperature regimes).
What it means is that in the past (when there was no industrial civilisation mining carbon out of the ground and releasing it into the atmosphere) there wasn’t enough flux in the various sources and sinks of the carbon-cycle for CO2 to initiate a warming. Instead you had to wait for changes in the earth’s orbital paramaters to start the world’s climate out of a glacial episode – once the warming started however, the ice core data shows that C02 levels rise shortly thereafter (cause unknown, although there are some hypotheses around), and this rise in CO2 intensifies the warming (‘cuz CO2 is a greenhouse gas dontchaknow). All of which is a jolly good thing, because orbital changes aren’t enough to effect a full deglaciation without a helping hand from the carbon – if the CO2 hadn’t come along then I’d be composing this post from the middle of a glacier. So anyway, absent something significant like an industrial civilisation or a massive bout of vulcanism, you need orbital changes to start the ball rolling and then carbon comes along afterwards and gives it enough of a wallop to get it over the line.
This time is different, because this time (as you may have noticed) there is an industrial civilisation mining carbon out of the ground and emmitting it to the atmosphere. So you don’t need to wait for a change in orbital inclination to cause an uptick in temps which then (via mechanisms unknown) causes a noticeable rise in C02 to prolong and increase the warming. We’ve cut out the middleman and, by virtue of the known properties of atmospheric CO2, we are going straight to the ‘prolong and increase’ part of the story directly.
#32, Phil, who ever said that every warming cycle is initiated by increasing greenhouse gases? Greenhouse gas emission can also occur as a positive feedback to a warming trend already in progress. Such a feedback tends to intensify and lengthen the warming trend. Remember, these warming epochs last 5000 years or so, while the CO2 kicks in after the first 800 years or so.
Now, you may ask how do we know that the current epoch is different? It is because in this case CO2 is leading. We know this because the carbon in fossil fuels actually has a different isotopic abundance than carbon that has been in the carbon cycle (all the Carbon-14 has decayed, for one thing), and we are putting enough fossil carbon into the atmosphere, that we can actually see the isotopic abundances changing. So, we know where the carbon is coming from. We know it is enough to cause warming, and we know that the release of carbon via the positive feedback mechanisms has not yet started to occur in this epoch of warming. When it does, we’ll see methane increase dramatically as well as CO2, and this likely will cause even greater warming. There is no great mystery here.
Re #32: [If 1000's of scientist are so sure then why cant we just have a straight answer on this - please.]
Maybe because you don’t bother to look for that straight answer. I know I’ve given my simplified, not-a-climate-scientist version in a recent thread; other people have given better ones. This is over-simplified, but over the past many millions of years prior to the Industrial Revolution, there was essentially a fixed amount of CO2 in the system. Some was in the air, some in the ocean. Those ice cores show what happens in that system: if the world gets warmer for some reason, CO2 comes out of the ocean (a process that takes several centuries), and causes further warming. Eventually all of it gets into the air, and you have an extended, high CO2 warm period. Then something causes the world to cool beyond a critical point, CO2 goes from the air back into the ocean, and you have a cool period.
Then humans came along and added a lot more CO2 to the system. This changes its behavior. To begin with, it cranks up the thermostat, so you might think you’d have the same cycle, just a few degrees higher. The problem, though, is that the coolings seem to depend on having lots of snow & ice in the polar regions, and if the planet’s too warm, you won’t get that.
“How can it be that chemical reactions cause a match to burn if the chemical reactions lag behind friction? Look, when you strike a match it’s just friction, right? Friction is what causes the match to burn, not some putative feedback effect involving chemicals in the match head.
Thus, the most reasonable explanation is that the chemical reactions do not affect the temperature, but rather that the temperature changes affect the chemical reaction – and it’s all due to friction.”
Sounds reasonable – but is utter nonsense. A little bit of friction provides the activation energy for further chemical reactions.
Let’s consider the ice age transition:
You say: “You can invoke all kinds of linked feedbacks effects plus an ‘unknown’ reason why the temperature initially kicked off..”
Look: there is no ‘chicken and egg’ paradox here. The ‘unknown’ reason is known; this is the change in the Earth’s orbital characteristics. Imagine if the Earth’s axis of rotation was pointed towards the sun, so that the North pole was in perpetual darkness. In fact, the Earth’s axis of rotation does change, and this leads to changes in the distribution of sunlight hitting the Earth. That’s your ‘unknown’ trigger – the Milankovitch cycle effect.
CO2 release is one amplification mechanism that is activated by the initial Milankovitch cycle effect; the lag is only an initial effect. Another amplification mechanism is the change in albedo as ice sheets begin to melt back: more bare soil and vegetation and less ice and snow mean less sunlight is reflected to space, i.e. a lower albedo. We can calculate albedo effects; we can calculate CO2 and CH4 radiative forcing effects, and we know (from ice core records) that glacial/interglacial transitions are always accompanied by rises in CO2 and CH4 and a reduction in albedo.
Putative mechanisms for CO2 release are uncertain – but if you defrost your freezer, and it’s full of food, then it will become a source of CO2 and other gases as microbes go to work. Most explanations work along similar lines. Unfortunately, noone was around with a video camera to observe what happened – but we have the record.
Now, consider that we are in an interglacial currently, and we’ve found new sources of CO2 (fossil fuels) to add to the atmosphere, and that we know CO2 played a large role in the complete glacial/interglacial transition (and we’ve added a lot of methane and N2O as well). In fact, we’re increasing CO2 at rates 30X greater than anything seen in the glacial record. Should we expect a strong response? Yes! How fast will the changes occur? Still uncertain… but we seem to be in an accelerating phase of CO2 emissions. It’s no accident that this past winter was the warmest on record since accurate global recordkeeping began in 1880 – and yet that’s a record that will surely fall in the next few years. Global cooling trends? Not unless we see record levels of volcanic activity – or an asteroid strike – and that would only be a temporary effect.
We need to plan for more of the same (heat waves, intense hurricane seasons, drought & flooding) while reducing CO2 emissions to head off potentially catastrophic effects, like inducing massive methane releases and ocean anoxia.
“Following a misleading account of my views in the Toronto Financial Post last month, a number of right-wing lobbyists have asserted that I claimed that an impending drop in solar activity would lead to global cooling that would cancel out the warming caused by greenhouse gases. On the contrary, I have always maintained that any temperature changes caused by variations in solar activity — while interesting in themselves — are not significant compared to the global warming that we are already experiencing, and very small compared to what will happen if we continue to burn fossil fuel at the present rate.”
As coal-fired emissions decrease, however, so will the sulfate aerosol cooling effect. It’d be interesting to see an estimate of the net effect of eliminating all coal emissions on a global basis – shouldn’t IPCC scenarios include this kind of specific estimate? (sulfate aerosols have a far shorter lifetime than CO2, so the CO2 from past coal combustion is still in the air; the sulfates are not). See the excellent links posted by Tavita in #19.
Re #35 “Who paid for it shouldn’t make any difference to any facts…”
In a perfect world, it wouldn’t. Unfortunately, we don’t live in a perfect world. Surely you’ve heard how the tobacco companies suppressed the research of their own scientists when that research revealed that smoking was harmful to one’s health? And big pharmaceutical companies have done the same thing. Research sponsored by big oil companies may well result in good science, but one can’t easily know for sure.
As for your inability to find some “facts” about global warming, you must not have tried very hard. Why not try the Science Links posted on the RC home page?
Re# 44 & 46 – Value of research funded by oil companies:
I would be very impressed if they or anyone else was able to fund the development of a climate model that like the others i) is based on known physics, ii) is able to effectively hindcast historical and paleological climate as successfully as the existing models and iii) predicts no or minimal CO2 induced temperate increase.
Perhaps this is an effective response to the skeptics. Meet that challenge and then they’ll be credible.
I’d be particularly excited if they, or anyone else for that matter, could come up with a model that effectively predicts the El Nino/La Nina climate pattern. I depend on direct rainfall capture alone and want to know how big a water tank I need to buy to keep my vegie patch going through future Australian summers.
Comment by Ike Solem “…it looks like China is taking some positive action: China Bans New Small Coal-Based Power Generators – shouldn’t the United States do the same?”
According to your link, this is only to reduce SO2 and soot, something the US has been doing for many years.
Comment by Steve Reynolds — 18 Mar 2007 @ 11:26 PM
There’s only a fixed amount of carbon that is mobile between the different components of the Earth system: atmosphere, oceans (hydrosphere), biosphere and lithosphere (surface rocks). So the process can’t carry on indefinitely. Unless a global civilisation works night and day to pump carbon out of the ground and into the air. The fossil fuels we are burning have been out of the equation for hundreds of millions of years. We need to take our foot off the accelerator.
search: biogeochemical cycling
White cliffs of Dover
calcite and aragonite
“Plankton cooled a greenhouse”
There’s plenty on this; it’s a FAskedQ — the answers are in the research; that’ll help find postings.
Look into it just a bit first, it will help you ask questions about the science if you read the frequent answers and those searches in the searchbox at top of page will turn up the answers, asked very often here.
“Once this process (co2 being incresed naturally -RO) starts – what stopped it from running completely out of control in the past?”
Again anyone step in. Here is a simplified explanation. There are several processes (can be called negative feedbacks) which stop the Co2 (on Earth…not poor Venus)from going “runaway” (“runaway greenhouse effect”).
The first is, is that rocks (silicate rocks), in the long term, remove the CO2 out of the air with a reaction with rain.
The warmer it gets, the more these chemical reactions increase (because it rains more when it gets warmer-ooops, what does that mean is happening now?).
Now this solution flows to the sea and dumps CO2 into the sea. in other words to paraphase from your high school chemistry that you were required to take: CaSiO3 + 3H2O + 2CO2 turns into Ca2+ + 2(HCO3- ) + H4SiO4).
Notice how the CO2 disappears. This is called the chemical weathering process and is part of the “carbon cycle.” In the ocean, types of animals absorb the carbon out of the water to make shells…they die and sink to the bottom of the ocean.
A second process to stop co2 from growing , is that the warmer it gets (the ice-covered lands disappear and the more trees and plants appear. They absorb more CO2 from the air and transfer it by roots deep in the soil where it combines with water to make an acid “carbonic acid” which disolves calcium silicate in rock to to make calcium carbonate (notice the word carbon in carbonate).
The calcium carbonate (carbon) is then transported in solution to the oceans where it can be dumped out as limestone.
Okay, those are the two basic processes. Otherwise, co2 gets reduced during ice ages when the Earth’s orbit changes the amount of sun energy hitting at least the northern hemisphere during the summer in regular (pretty regular) three cycles of about 26,000 years, 41,000 years and 100,000 years (Milankovitch cycles).
You know the routine: Cool the air. Cool the oceans which can hold more co2 in solution (think of your cold versus hot pop bottle). Now increase the ice on Earth. This makes higher winds by air coming over ice, rapidly sinking and making winds. With an ice age, more dusty land is exposed as sea levels drop as water becomes ice. This carries more dust. Dust has iron. More iron feeds more plankton in the oceans. More plankton (plant variety) eats more co2 and sinks.
In ice ages, the ocean currents often also get more active because of a bigger difference in temperatures between the poles and the equator and this allows even more co2 to be absorbed (subducted).
That is a simplified expanation that leaves a lot out.
Comment by Richard Ordway — 19 Mar 2007 @ 12:24 AM
RE#45, This was discussed from many perspectives at the “Swindled” thread; my attempts can be viewed at #150, #202, #291, but to quote one of the moderators:
“Response:AFAIK, people don’t know exactly why CO2 stopped at 280 in interglacials and 180 in glacials. It doesn’t have to be feedbacks: there could simply be some reservoir that is exhausted. Also, thats for the previous 4 interglacials: before then, EPICA shows 250. This again is unexplained – William”
‘Some confusion surrounded the views of the RMS scientists yesterday after Prof Hardaker told the IoS that he could not think of a case where a scientist had overstated the position. He did however mention a statement by the American Association for the Advancement of Science that described an “intensification of droughts, heatwaves, floods, wildfires and severe storms” as “early warning signs of yet more devastating damage to come”.
He said he did not disagree with any of this, but thought the AAAS should have made it clear what could be justified by the scientific evidence and what was based on judgement. He pointed out that he and his colleague were not experts on climate change. ‘
So after all this fuss, he did not disagree with any of the statement, and ‘he and his colleague were not experts on climate change’. Strange, since the BBC Today website still has the interview http://www.bbc.co.uk/radio4/today/listenagain/ram/today2_climate_20070317.ram with the headline ‘Two of Britain’s most senior climate researchers have told the BBC that scientists have been overplaying the message on climate change.’. Still, if you wanted to get lots of pulicity for outfit like Sense about Science (who have some slightly dodgy links to the RCP/Spiked crowd), then this nonsense would have done you no harm…
I’ve been following the “pro” and “cons” for a while now and still can’t get to some conclusion of it all. On questions I have for instance is: The CO2 we are releasing now is that not previously free CO2 that have been captured at some time in history? And if so, are these volumes not already in the climate system and we are actually not adding anything that did not exist before?
Re #35, climate change is relative is the answer. Today millions of people live along the coasts of the world, when the seas rise due to climate change they will be in trouble, it does not matter that 50 million years ago the earth was 5 degrees hotter and the seas 70 meters higher does it as it did not impact anyone ?
It is all about forcings or which the earths albedo and vegetation is the strongest followed by greenhouse gases. Both do not need to be high for warming to occur either can cause warming or cooling for that matter. 10,000 years ago the earths natural cycles (known to us as miltankovitch cycles) starting to bring us out of an ice age and hence the albedo effect was the cause of this warming. As you have been told it takes some 800 years of warming before albedo and vegetation had been effected enough although RC tell us that it may not have been this long. Anyway the source of the CO2 is most likely the oceans which absorb CO2 when it is cold and release it when it is warmed and it is this released CO2 that then causes further warming of the atmosphere.
In the modern world 280 ppm seems to be the earths natural limit and we are not at 390 ppm due to industrial burning. Further burning will cause steadily increasing CO2 levels and hence further warming.
Yes, most CO2 we are producing at present was at some point in history captured and converted to fossil fuels, which then remained safely underground (and outside the climate system) until we recently started re-releasing it into the atmosphere.
I should maybe start by stating that I recognize the fact that earth is warming… And with that out of the way… After considering your answer I still don’t understand why many claim that the CO2 levels have never been this high when evidently “all” the CO2 we’re releasing must have been around some point in time. I understand the consequences at present and future time for mankind but in the history of earth (and I’m thinking rather recently) there must have been worse situations than the one that is proposed to be?
Rob…the problem is I think pre-Industrial Revoluton levels of CO2 were 270ppm with a very small population and now C02-equivalent levels are way over 400ppm with a population heading towards 9.5 billion by 2050. These people need to be fed, housed, clothed, and have access to clean water and good sanitation. If extreme weather events increase and the temperature gets hotter, then this has severe implications for that larger population. If there were still less than a billion people in the world and the temperature rose naturally rather than being forced there wouldn’t be such a problem. Isn’t this what we are all really worried about?
Exactly, we should worrie about the consequences of a warmer world rather than try to rectify something that we might or might not be able to influence. Is it not so that a very high percentage agrees and recognize that the world is getting warmer (independent of source)? And are we also not on agreement that this warming will continue for a long time regardless of any action taken to prevent that? If so, shouldn’t the prudent way of the humankind (as history have told us) be to adapt?
The claim about “CO2 levels never been this high” is made (as far as I know) for the last 650,000 years (this is found from analysing air bubbles in ice cores).
With a little googling I found this temperature graph: http://www.scotese.com/climate.htm which has several maxima at ca 22 deg C global T, for example in the Cretaceous some 100 million years ago (currently we’re at 15-16 deg C). Presumably CO2 concentrations were also higher then (but I am no paleoclimate expert).
However, as people have often pointed out in the hockeystick discussion, whether CO2 levels were higher at some time in the past is really not the issue*). Even if we had no clue whatsoever about the climate before 1800 there is plenty of evidence that the theory of global warming is sound and we’re involved in a dangerous global experiment.
*) Of course I don’t mean to deny the importance of paleoclimatology. It it is a good thing to have the complete picture, and to check our theories wherever we can.
“…I still don’t understand why many claim that the CO2 levels have never been this high when evidently “all” the CO2 we’re releasing must have been around some point in time.”
Bear in mind that the coal / oil deposits we’re burning through weren’t laid down overnight. The CO2 we’re re-releasing WAS all in the atmosphere in the past, but not necessarily all at the same point in time (unless you go billions of years back, before life on the planet).
[[You don't explain why there's global warming on Mars, Jupiter, Triton and Pluto. ]]
All we know about Mars is that one of its polar caps has shrunk a bit in the past three years. That proves exactly nothing relevant to the overall thermal balance of Mars.
Jupiter is not undergoing global warming. Where did Lindzen get that idea?
Triton? Where is Neptune in its orbit just now? Ditto Pluto. Neither Triton nor Pluto has an atmosphere worth speaking of, but they do have summer and winter. Is Lindzen aware that Pluto takes 248 years to go around the Sun, and therefore that its seasonal change in any direction will last a lot longer than on Earth?
Coming up at 10am on C-SPAN, another episode of “Stop Interfering with My Research.” Today, the big boys go at it. The CEQ head’s name is actually James Connaughton, a fairly important policymaker on climate change, but who is seldom seen or heard. C-SPAN usually repeats these hearings, so check the schedule.
Global Warming Research
Rep. Henry Waxman (D-CA) chairs an Oversight and Gov’t Reform Cmte. hearing on claims of poli-
tical interference with government scientists & their research on climate change. Witnesses include James Hansen, Dir., NASA Goddard Inst. for Space Studies; John Connaughton, Council on Environmental Quality & others.
thanks for the replies so far – I do appreciate the time people take to put forward information but…
All of this started off in the 1970′s with the simple idea that Co2 warms the atmosphere. This has developed so that now ice coverage, methane, CO2 etc all contribute. Throw in solar and cosmic activity and I’d say you have a very, very complex system youâ��re trying to model. Anyone who is willing to take a firm stand on any prediction being right is a brave sole.
A computer model of this would have to take account of every contributing factor in exactly the right amount for its predictions to have any chance of being right. Not only the initial conditions but also the exact nature of how everything interacts with everything else. Should any of these be out (or some other as yet unrecognized factor be missed altogether) then after a few interations the model would bare no relation to how the world’s real climate will change.
Perhaps this is why the GW predictions I read range from â��not too badâ�� to â��the end of life as we know itâ��.
Other theories like relativity or quantum mechanics stand or fall on very definite predictions. The predictions from GWT have such a wide variation that the theory itself seems very under-developed.
[[I watched the program and read the rebutals but still cannot for the life of me understand if CO2 levels lag behind the temperature by 800 years how CO2 causes the temperature to change. ]]
Try reading the past posts in the blog. RealClimate and posters have covered this many, many times.
We know more CO2 in the air raises the temperature of the ground. That’s basic radiation physics which goes back at least to Arrhenius in 1896. If any temperature increase for another reason raises CO2, the CO2 will raise the temperature further. It can’t be avoided unless there’s some counteracting factor, and no one has ever found one despite diligent search for many decades.
[[If I understand this correctly, an initial rise in temperature causes an increase in CO2 which then causes an increase in termperature which would cause another rise in CO2.
Once this process starts - what stopped it from running completely out of control in the past? ]]
The math governing it is essentially a converging series — each increment is smaller than the last, so the total comes to some finite sum. Compare the series 1 + 1 + 1 … which diverges to infinity, with 1 + 1/2 + 1/4 … which converges to 2.
[[I've been following the "pro" and "cons" for a while now and still can't get to some conclusion of it all. On questions I have for instance is: The CO2 we are releasing now is that not previously free CO2 that have been captured at some time in history? And if so, are these volumes not already in the climate system and we are actually not adding anything that did not exist before?]]
Most of the carbon on Earth is not in the climate system, but in sedimentary rocks on the ocean floor. It does eventually get recycled to the air, but the process takes millions of years.
You’re right that the total amount of carbon is fixed — mass is conserved in any non-nuclear reaction. But what’s happening now is that carbon is being released from the rocks — fossil fuels — and dumped into the atmosphere faster than natural recycling can handle it.
[[I should maybe start by stating that I recognize the fact that earth is warming... And with that out of the way... After considering your answer I still don't understand why many claim that the CO2 levels have never been this high when evidently "all" the CO2 we're releasing must have been around some point in time. I understand the consequences at present and future time for mankind but in the history of earth (and I'm thinking rather recently) there must have been worse situations than the one that is proposed to be?]]
There have been times in geological history when CO2 was much higher and the world was much warmer, and life survived. It will survive now. But the transition to that warmer state will be faster than our agriculture and our economy can handle. In the Jurassic when the sea level was higher, there were no cities built on the coastline. There are now.
The model problems are not so severe as you make them out to be.
1. Some factors are less important than others, so it doesn’t matter whether we know them accurately, as long as we’re in a reasonable range. There are also some statistical ‘tricks’ to deal with uncertainty, as they do in the ClimatePrediction project.
2. Some important factors (what CO2, CH4 etc do with radiation) are well known from independent experiments.
3. It gives A LOT of confidence that the models reproduce measurements fairly well, not only over time, but also in space: temperature and rain distributions over the globe for example.
There is the matter of lacking knowledge of ice dynamics (melting) of course, but from what I gather this will probably make matters worse than better.
And what’s the alternative? Just ignore the best predictions science has to offer?
“On questions I have for instance is: The CO2 we are releasing now is that not previously free CO2 that have been captured at some time in history?
And if so, are these volumes not already in the climate system
and we are actually not adding anything that did not exist before?”
My over-simplified explanation was too simplified on how Earth’s systems keep CO2 in check. I named only two general processes.
There is at least a third important process at work that keeps the CO2 naturally in check…sometimes known as biological sequestering or a biological pump. This is also part of the carbon cycle.
This third process is approximately as follows (again very simplified)… the CO2 levels rise, Earth’s average surface temperatures rise.
Now trees, plants, algae (in comparatively now stagnant oceans and lakes-[algae are plants]…think scum on a summer pond surface) and swamps and bogs spread massively.
Oceans often become more stagnant during long warm periods because of fewer temperature differences between the poles and the equator.
The warmth spreads to almost the poles. Palms and ferns grow at the equivalent of the artic circle area…ie most of the Earth’s land surface now becomes covered by swamps and the oceans by algae.
Trees, plants, algae and other single-celled animals absorb CO2. They die and are covered by newer trees, plants and algae in this stagnant wet swamp/bog/ocean envriroment.
They sink (in swamps, bogs and oceans) and are covered my more plants and trees. After a while (millions of years) this is turned by pressure and heat…into coal, oil and gas full of…carbon.
It basically stays this way…unless we humans suddenly dig it up and release it to the atmosphere by burning oil, coal and gas. This carbon now combines with oxygen to form…co2 when you burn it.
Guess what one of the biggest geological ages was called when this “biological sequestering or biological pump” was occurring about 300 million years ago…the “Carboniferous age” (note the word carbon).
That is a third major process that keeps co2 in check…and has severe implications for today and the future. In short…”this ain’t natural.”
on the American Institute of Physics website. Arrenhius’ (1896) prediction was that for a doubling of CO2 there would be roughly 5degree increase in temperature, I believe the current estimate for this sensitivity is a little lower.
I wonder if he intended for us to test his prediction experimentally?
1.. “The model problems are not so severe as you make them out to be.”
you can only know how severe they are by waiting until the predictions have come true – or not. If it turns out to have even a slightly different effect that you origianlly thought your model can be way off.
2. “Some important factors (what CO2, CH4 etc do with radiation) are well known from independent experiments.”
experiments that actually show their overall effects on the real climate, or do they just extrapolate an effect in the laboratory.
Am I wrong in thinking that the different models report widely varying predictive effects (between 1-6 degree temperature changes for example)
How can they be accurate yet produce widely differing at the same time
[Response: There are two parts to making a projection. The first is the scenario that is used that determines how much CO2 etc. might change, and secondly, the physical model is to project the change in the climate. The range you quote is for both sorts of uncertainty, and most of it is related to the different scenarios, not the different models. The model sensitivity is significantly less for any one scenario. See the SPM for details. - gavin]
Carbon trapped in limestone deposits is returned to the atmosphere when the limestone is subducted during a plate collision. It can then react with silicate rocks
and the CO2 is expelled, through volcanoes funnily enough (so much for the assertion that volcanoes emit CO2 – it’s often fossil atmosphere anyway).
And of course, the organic stuff can be returned when their strata are eroded and the material is then oxidised.
I’ve been busy & need to catch up, so this might be off topic, but several posts ago Chris Mooney raised the issue of Al Gore being incorrect on something in AIT, and how that might damage credibility or something.
If Gore underestimated GW, then that is a bad mistake & morally reprehensible (if done purposely). If he overestimated the harm, then that is perfectly okay.
The only debate in my view is between the scientists, avoiding false positives (not making a claim re GW unless they are extremely sure), and the environmentalists (and everyone else), avoiding false negatives (being cautionary in assuming and trying to prevent the worst). So, the skeptics and contrarians and denialists are all in the “avoid the false positive” camp, with only the scientists having a morally valid reason to be there.
So any mistake on the “assuming the worst & trying to prevent it side” is a non-problem. It’s perfectly okay. That’s were everyone, except the scientists, should be.
Comment by Lynn Vincentnathan — 19 Mar 2007 @ 11:45 AM
re #85, #79;
You needn’t take offense, Phil, the word “ignorant” was used in its literal rather than pejorative sense.
You do have a point. Climate models have a lot of utility in investigating climate, but the boundaries between their uses and abuses are complex and controversial. It’s not especially easy or obvious what we should trust about them and what not to.
The public and much of the scientific community focuses on the conceptually simple use of prognostication that the IPCC report cycle drives. (Note that it’s prognostication and not prediction; all of the climate models of the future are predicated on CO2 concentration scenarios, which in turn depend on 1) human behavior and 2) carbon cycle feedbacks; there’s no way around the first part at least.)
How reliable these prognoses are is not better than the scatter among them, which is large. It may be worse than that, because there may be some unconscious bias toward producing a “typical” result among the modeling centers. However, it is difficult in practice to imagine how such biases might operate.
So it is a bit of a quandary.
The less you believe the models, the more vigorously you should support carbon mitigation. I feel compelled to come out and say this on occasion, since most people get it backwards. The weaker you think the science is, the bigger the risk you believe we are taking, and hence the more effort you should put into avoiding the worst cases. The cost of overreacting to benign climate change scenarios has to be balanced against the much larger cost of overreacting to catastrophic ones. The cost of the catastrophes increasingly dominate the more uncertainty you place upon the estimates.
It is also important to take note of the fact that despite enormous motivation to do so, nobody has been able to build a model that reasonably represents contemporary climate that has a greenhouse gas sensitivity different from the model consensus by a factor of greater than two.
The models continue to fail to represent local changes well enough to rely upon for local policy. Whether they can be improved enough to do so remains an open question. I think it is too soon to give up, but late enough to start exploring alternative design methodologies. That is a topic that is worthy of a real scientific debate.
Your question whether we “can accurately model the entire atmosphere” depends very much on what sort of accuracy you are looking for. The models produce storms that go where storms go and, as of recently, hurricanes that go where hurricanes go. The gulf stream goes where the gulf stream goes, and so does the Kuroshio and the Antarctic current. The sea ice grows and shrinks at roughly the right times and rates. The intertropical convergence zone and the El Nino, however, remain wretched. Make of this what you will. (I make of it a living, myself.)
But the climate sensitivity to CO2 is essentially known. There’s very little evidence that would place it far from 3 degrees C per CO2 doubling, and a great deal that puts it near that quantity. Models agree with other evidence on this matter. It’s not really an open question; any scientist proposing a dramatically different value at this point would have an awful lot of ‘splainin’ to do.
“…while someone (admittedly not me) may fully understand a model I just question the idea that you can accurately model the entire atmosphere of a planet. …” – PhilC
As long as we’re mixing things, a prediction of the weather to be on Thursday morning requires a degree of accuracy akin to threading the eye of a tiny needle; hitting the broad side of a barn 200 years from now doesn’t.
Any person should question the idea that you can model the atmosphere of a planet… but then, assuming that’s the question of interest (and not, how can I inject doubt into scientific discussions of climate in order to prevent governments from taking action?) then you’d want to look at weather models, and how climate models are derived from weather models, and how ocean circulation and heat transport is modeled, and how ocean models are coupled to climate models… and so on. You’d want to compare past model predictions to reality (see for example http://www.realclimate.org/index.php?p=148 “Planetary Energy Imbalance”)…and then you’d realize that the models do a pretty good job.
Of course, there’s always something that might be missing, but that’s true for any model – a model of air flowing over an airplane wing, a model of a bridge. That’s why comparing models to observations matters; if there’s a persistent discrepancy it can tell you about what your model is missing (for example, early models didn’t include aerosol effects). That’s how science is done.
If you ignore the facts after they’re presented to you and persist with the same discredited arguments, as Lindzen et al do, then you simply lose all credibility.
“As long as we’re mixing things…. hitting the broad side of a barn 200 years from now doesn’t.”
What am I mixing?
The current models seem to predict different ‘barns’ depending on who’s running the model (i.e. different temperatures and climate effects etc) – how come they differ so much if they are essentially accurate.
Mark, that’s the difference between what you see and what you get (grin).
You old enough to remember the 48-star flag? I’m still flying mine, it hasn’t worn out yet — it’s a grid (stars aren’t offset), six rows. You don’t see all eight columns in the WSJ Editorials picture.
Trust me, that’s the flag from before the upstart Alaska and Hawaii Territories intruded themselves into the country (and the current staggered-to-fit-fifty star layout became the official flag).
Aw, you knew that, I’m such a sucker for a good troll sometimes. Gulp.
Michael Tobis (#87) was correct – I was using “ignorant” and “ignorance” to describe your apparent lack of knowledge about global climate models. Had I intended to disparage you personally, I would have chosen some other term (and the comment would surely have been deleted by the RC moderators).
As others have pointed out on this and other RC threads, computer models used to make forecast are commonly run mutiple times using different starting values to account for the known (or expected) variability of the input parameters (i.e., the assumptions on which the model is based). The result is a range of possible output values (predictions/prognostications, whatever you want to call them). Yes, the predicted magnitude of global warming is a range of temperature values – usually these predicted values are assigned some degree of certainty akin to confidence limits in statistics. It will take some time to verify the accuracy of these predictions, but the fact that they all predict global warming should be alarming to everyone – keep in mind that one degree C is almost two degrees F, and a rise in global mean temperature of even 1 degree C over a couple of decades could be expected to have very serious implications for sea level rise, animal and plant survival, disease outbreaks, etc.
Re #37: Richard Ordway — My understanding of the LGM to Holocene temperature increase of 6–8 K is that only about half of that can be attributed to so-called greenhouse gases. (My amateur attempt only supplies about 2 K.) The rest of the temperature increase might be due to albedo changes?
Comment by David B. Benson — 19 Mar 2007 @ 3:42 PM
Re #45: PhilC:
There’s a mathematical way to understand why it might not run away: The positive feedback is smaller than the initial kick. So, if we take the initial kick as having one unit of strength (in other words, call it 1), the positive feedback could be 3/4 the size. Then that 3/4 causes a feedback 3/4 the size of that one, etc:
1 + 3/4 + (3/4)*(3/4) + (3/4)*(3/4)*(3/4) + …
This is what is called in mathematics a “convergent” series, which adds up to 4. So the final effect is that the change is 4 times as big as the original effect.
Plus, there could be a time delay as it takes effect. So, for example, the solar change that kicks it off happens at time t=0, but then t=100 years later the initial 3/4 takes effect. Then at t=200 years the next 3/4 takes effect, etc. What you’d see is the CO2 rise trailing the climate change in precisely the observed way.
It is possible that the feedback was bigger than the initial kick, say 1.2. Then the series is:
1 + 1.2 + (1.2)*(1.2) + (1.2)*(1.2)*(1.2) + …
This series is called “divergent” – it never stops growing. I have heard that it is believed that this is what happened on Venus. (Of course, in any physical system you eventually get cut off – you run out of carbon, for example.)
What we really need to fix is our science education.
The final vote of the debate was really a notice that society is not going to make a determined effort to restrict ghg emissions until our infrastructure is flooded, and we are living in a tent on Mt Ararat. Noah did, and so can we. I have lived in a tent and herded sheep, it is not so bad â?? if you have those skills.
In only a 150,000 years, the waters will recede and we can reclaim places like New York City, Houston, London, Istanbul, Bombay, and Shanghai. Not to mention every major refinery in the world. Of course, without those refineries, even inland cities could no longer function.
We have a society that does not understand science: not climate science, not economics, and not geography.
Piers Corbyn, the meteorologist that supplies long range forecasts for industry says the IPCC in fairness should include a temperature record going back to the end of the last ice along with the CO2 record of the same period. Do you agree with him?
[Response: Umm... sure. If such a thing existed. But we don't even have good data for the global mean back before 1000 years ago (and Mr. Corbyn would probably dispute that also), so how we can have it going back 15,000 years is a little odd. The graph he uses appears to a very rough copy of one of the Greenland ice cores, but that is hardly typical, and certainly not a global mean. - gavin]
Re #97: At some point we need to remind ourselves that many interlocking feedbacks are involved: GHGs (with water vapor doing the major part of the work as always), albedo, dust clouds, carbon sinks, sea ice, ocean currents, atmospheric circulation patterns, vegetation, plankton, etc. Bear in mind that the entire climate system is being shifted into a different state. *Everything* that can change does change. That certainly makes modeling it difficult, but it turns out to not be impossible:
I’ve linked it before, but since we’ve been talking ice ages and models on this thread these fresh results are very much worth reading. I’d love to get the opinion of one of the modelers on this, but from my humble POV these results seem very good indeed (although not perfect by any means, plus they avoid dealing with the Mid-Pleistocene Transition).
Re #101: Steve Bloom — Yes, many interactions occur. My goal is to keep it simple as long and as far as possible.
Regarding your link, my amateur reading is that the work is quite good, but with the important exception of the transition from the Eemian (last previous interglacial) to the first stade, which did not model well…
Comment by David B. Benson — 19 Mar 2007 @ 5:49 PM
Hearings Clear Up Misunderstanding About Censorship
I managed to watch several hours of the House Govt. Reform Committee hearing on scientific censorship of climate change research before C-SPAN cut away to cover the House. The full hearing will probably be shown later. But no matter. It was all a big misunderstanding.
The hearings were to focus on why the Bush Admin. had deliberately tried to prevent government scientists from giving media interviews on climate change and on the selective editing of important policy documents produced on climate change such that the edits did not accurately reflect the science.
Witness Phil Cooney, formerly and presently of Big Oil testified he only made changes he thought should be made and that James Mahoney, the then head of the Climate Science program didn’t include most of his changes anyway. No harm, no foul. It was agreed that having an oil man in that position was probably a bad idea, certainly from a PR standpoint.
Witness George Deutsch, the former NASA press information officer, testified that he was only a messenger boy, telling James Hansen and others what the big boys at NASA HQ on the 9th floor wanted done. Specifically that they didn’t want him to give interviews, especially after the one where Hansen said that 2003? 04? was the warmest year on record. Deutsch, who did not have a college degree at the time of his tenure at NASA and was chastised for misleading people that he had a degree has now graduated and runs a radio call in show for the mentally ill. Not qualified for this one either or competition for Limbaugh?
Witness James Connaughton, still head of the Council on Environmental Quality praised Dr. Hansen and said that they invited Hansen to make a presentation to them on non CO2 GHGs and this led to the various international agreements to reduce methane. Hansen himself said this was a success.
But witness Hansen was not living in the same bizarro world as these guys and reminded the committee that obstructing scientists would not make the problem of global warming go away, it would just make it harder to solve. He wouldn’t give a specific amount when asked how much federal money should be spent on solving global warming based on a range of $3 billion (now spent) vs. $350 trillion (amount needed to immediately solve problem in U.S. according to one congressman). He said that more money should be spent on developing renewable energy and not just on nuclear energy, a favorite of Connaughton. The $3 billion figure seems to be quoted a lot more since I exposed the phony $6 billion number claimed by the Admin. for some time, as a lot of hypothetical tax credits and unrelated work spray painted green.
The hearing went off the paved surface and up a dirt road on several occasions with some time spent debating whether Al Gore’s house is more energy efficient than Bush’s Crawford ranch. Members also agonized over whether it would have been better if Bush had taken the high road on Kyoto or climate change in general.
The issue of whether Hansen endorsed Kerry for president because he had received a $250K prize from the Heinz foundation came up because Republicans wanted to portray Hansen as a hypocrite since the issue of bought and paid for staff had come up regarding Cooney’s hiring. No evidence was presented that there was any connection with the endorsement of Kerry and Hansen said he supported any candidate who took the issue of global warming seriously, including John McCain.
There was also some discussion of Hansen’s comparison of the Administration’s censorship of scientists as like that of Nazi Germany and whether this was appropriate. Agreed. He could have chosen a less inflammatory example. USSR, N. Korea, Cuba, Myannmar (a little too esoteric perhaps), Turkmenistan, Iraq (pre-2003), Iran, Libya, Syria, the former E. Germany. Why play the Hitler card when you have Belarus and Zimbabwe to choose from?
This led to the question of whether government employees have the right to speak out publicly when they disagree with a stated policy. Hansen said this was allowed under the First Amendment.
And on the subject of debates and censorship, Hansen said he would not censor any of his approx 120 staff on a scientific matter, but he also did not encourage debates with the handful of climate contrarians, since it gives them an apparent equal status and a platform from which to cherry pick facts that would likely confuse a lay audience. Not that anything like that would ever happen.
The people most worried about bird flu fall into two groups — those actively trying to educate the public and improve public health, and those who are improving their personal private property and stocking up what they expect to need when public health and services break down during a crisis.
The “Reveres” who write Effect Measure commented on this a while back, saying they are not taking up stockpiling and planning for personal survival, they are spending their time and effort trying to educate people about how to prevent the problem.
I have no problem believing that Mr. Bush’s private ranch is very energy efficient, and likely has all his family needs to be self-sufficient.
I would like to thank those who patiently have answered the questions posed by PhilC. You may not convince him, but you have provided the rest of us with a wealth of information and explanation.
So please correct me if I’m wrong, but this is what I glean from the discussion. We have recovered from past glaciations because orbital variations have started a warming cycle that released, in 800 years or so, CO2 from the oceans and other sources, which resulted in additional warming for thousands of years until CO2 was stable in the atmosphere (since CO2 is not an infinite resource). Then over geologic time, CO2 was sequestered back into the ocean and rocks, cooling the planet.
But now, we do not have the orbital change driving the warming, but instead the increase in CO2 has resulted in jump starting the warming. The end result should be that additional CO2 will be released as the planet warms, until CO2 again is exhausted from “natural” sources.
EXCEPT that at this time, we have dumped (and will continue to dump) huge amounts of fossil CO2 into the atmosphere. This fossil CO2, combined with the CO2 that will be released as the oceans warm, will lead to conditions which have not been seen for hundreds of millions of years.
This suggests to me that it is going to get very, very hot here on Earth, and this with continue for a very, very, very long time.
Re 95: Nevermind ‘magna est veritas, et praevalet’. More like ‘veritas fortis est, et praevalebit’. I sincerely hope that Gore reads RC and has learned from the experiences of others. Monckton is attempting to hook Gore by playing the ‘southern gentleman’ card. Gore should refuse to play this game, not get sidetracked from the real job in hand, and walk away.
Re 29: [What technology presently can replace coal or sequester its exhaust?]
Considering the abundance of coal and the affordability of its electricity, none that I’m aware of today. But it’s in development, e.g. Integrated Gasification Combined Cycle (IGCC) and Supercritical Pulverized Coal (SCPC). Web searches provide info on these systems. The government consideration I referenced in #24 in conjuction with similar international efforts, driven by science, could result in economic drivers that make these or other similar-purpose systems reality.
Re #108, don’t go from a skeptic to a extreme convert. You have the jist of it right but remember all CO2 is doing is trapping more heat that the earth is reradiating back into the atmosphere. This is a known amount (measured in w/m2) and hence at the present moment the warming that is occuring is going to be 3 deg C higher that it was in 1750. The world is not going to roast or die and humans will still survive etc but it will costs millions of people their livlihoods and lives, unfortunately mainly coastal and poor peoples.
At the present moment in time climate change is deemed to be linear in nature and that is true of CO2 warming, however some of earths other systems such as the Oceans, vegetation and frost/ice will be influenced by this warming and hence additional CO2 could be released into the atmosphere as vegetation, tundra and oceans contain a lot of locked up CO2 in very large amounts. Current climate models take into account many factors, however I do not believe that permafrost melting, rain forest depletion or oceans becomming large scale sources etc are factored in they are mainly based around fossil fuel burning scenarios only I believe but I could be wrong. Additional releases of greenhouse gases from natural sources could render the warming more non linear and then we could see increased warming. This is known as sudden/abrupt/catastrophic climate change and I thought that some of this stuff was going to be in the 4th IPCC report but apparantly it is to attention grabing and alarmist to warrant its inclusion at the present time, maybe the 5th one will add it in.
Thanks to everyone for their replies – I remain skeptical (although strongly object to the term ‘denier’)
I have a degree in physics and MSc in applied optics – all a bit out of date now but I am familiar with science. I’ve also spent 25 years building commercial software models of relatively simple systems & know how easily they go off in wrong directions when one tiny factor is missed out – in which case, the longer you let them run the more ridiculous their results.
You can use models to design airplane wings, camera lenses, bridges, buildings etc. but these are very well defined systems. The planet is a part understood living system – massively more complex and to say we can accurately model this is just naive which won’t stop people from making a living out of doing it.
If you model a plane wing and the plane doesn’t fly you quickly find that the model was wrong but climate models are making predications for 10,20,100, 1000(!) years in the future which conveniently means no one can say they’re wrong. Making them ‘nonfalsifiable’ and a nonfalsifiable theory is not a scientific theory.
It would be more responsible if predications from these models carried a large notice “this is from a computer simulation and may be wrong” – but they are reported in the newspapers with such certainty, especially when the predictions are dramatic (see the front cover of the UK Independent most days).
And I still don’t like this T-Co2 lag. If GWT had never been thought up most would simply say that heat produces CO2 end of story but all sorts of other processes have to be introduced so that the Theory still ‘works’.
Despite all your best efforts many people are skeptical about man-made global warming -why?
While some people are just contrary by nature, a lot of very sensible people are feeling we are being manipulated into a belief (see the “have you say” discussion page on the BBC website each time this subject comes up – many people just don’t buy it).
Media reporting of science (in general and GW in particular) is atrocious. Other than “we’ll die, it’s your fault, if you dont believe it you’re being stupid” there is no real public discussion of the theory, no public debates between pro-con, very little chance for the public to really think about it.
Our lives are now being changed for us with no real discussion. In the UK new “Green Taxes” have been introduced to make things that we have to do more expensive but which have zero impact on any CO2 levels. Our Environment Minister says the debate is over and the spokesman for our liberal party even tried to stop the TGGWS program being transmitted (some liberal).
If the anti-man-made-global-warming arguments are as weak as you say then put them all on TV and have experts from all sides debate the facts in public and keep debating it in public until every argument is resolved.
Whatever the truth is it can always standup for itself
Re #111 “remember all CO2 is doing is trapping more heat that the earth is reradiating back into the atmosphere.”
Not so: it’s also acidifying the oceans, with possibly very serious consequences, discussed on this site under the heading “The Acid Ocean â�� the Other Problem with CO2 Emission”; changing the physiology of plants and bacteria and their competitive interactions in complex and incompletely understood ways (it’s often claimed agriculture would benefit as plant growth is increased when CO2 levels are increased in greenhouses, but there are considerable problems in scaling up these results); and reducing oxidation of methane in soil. Those are the other effects I know of. Probably there are others known, and yet others no-one knows about.
Yes, that’s pretty much how my non-climatologist head understands it.
The big unknowns for the amplified warming aspects of this problem being
(i) how large the ‘natural’ carbon reservoirs are
(ii) what is required to release them
(iii) how fast they’ll emit to the atmosphere
(iv) are there any negative feedback mechanisms that might dampen things out
Re #113 yes but these effects are not evident in climate models are they. Climate models are not earth models or ecology models but models of heat movement and where it will be warmer (and cooler) in the future not what species are going to die out or how much acidification of the oceans will effect life in them.
Re # 112
“Despite all your best efforts many people are skeptical about man-made global warming -why?”
I don’t know, but a significant number of people in the U.S. are skeptical (or deny absolutely) the theory of evolution, and a significant number of people still think Saddam Hussein had weapons of mass destruction and posed a serious and imminent threat to the U.S. (Why are people who fight tooth and nail against paying an extra $100 or so in annual property taxes to fund their local school so willing to support a war that could end up costing the country a trillion dollars?). I’m afraid the answer lies more in social psychology than in the absence of public debates – evolution v.s creationist/ID has been debated to death in public forums and I doubt any minds have been changed; the rationale for invading Iraq continues to be debated almost daily on U.S. television news shows and it doesn’t seem that many minds have been changed). There is one goal in a debate, and that is to win the debate – not resolve a complex scientific (or political) issue. The real debate about the details of AGW and the reliability of the computer models is, appropriately, carried out at research conferences and in the pages of peer-reviewed scientific journals.
106 Hank Roberts [[The people most worried about bird flu fall into two groups --- those actively trying to educate the public and improve public health...]]
Let’s look at how the public perceives the threats of Bird Flu, Y2K, Global Warming…and how the scientific community actually warns them.
People say…oh “those scientists” are always warning of things that don’t come true.
This is a red herring and often used by people hostile to science. Look at the PROBABITIES that scientists assign to possible events. That is the key.
Did you EVER hear of the scientific communtity stating thre is a 90% probability that Y2K will happen…no. Perhaps they said it is possible so we have to be serious about it.
How about bird flu. When one of the spokes-person researchers was pressed about probability of it happening by the press, she stated that she did not feel comfortable doing that…but that the risks were high enough to be taken seriously…
Now, for global warming…”there is a 90+% chance that it is happening and we humans are causing it and it will continue for at least 100 years.” Paraphrased for the IPCC, 2007
See the difference. The scientific community tries to qualify the threat level…and is very careful and conservative about trying NOT to “scare people” or make big predictions that if wrong could come back to haunt them.
Anthropogenic climate change, in other words, is considered to be in a very different threat category than bird flu or Y2K.
Comment by Richard Ordway — 20 Mar 2007 @ 11:02 AM
#112 Phil [[If the anti-man-made-global-warming arguments are as weak as you say then put them all on TV and have experts from all sides debate the facts in public and keep debating it in public until every argument is resolved]]
No Phil. You don’t understand how science works. In public debates, truth is utterly unverifiable because one side can make up fake facts to refute actual facts…it is a fool’s game.
In the juried, peer-reviewed journal process, truth can be and is eventually vetted out.
Apparently, even you can’t tell from the public debates between Gavin and Lindzen who is telling the truth. Public debates are not useful for determining the truth.
In the USA, public debates on evolution had many anti-evolutionists winning debates in the 1800s. Evolution is quite provable and yet the truth was not vetted out by public debates.
The scientific community needed a vetting process that worked…the only thing they found, as troubled as it is, that vetted out the truth was the juried, peer-review journal system. It is a tried and proven system.
Public debates may raise public awareness of an issue…but whoever is the better liar or debater wins…truth is the loser.
Comment by Richard Ordway — 20 Mar 2007 @ 11:32 AM
What you are forgetting when you are bothered by the lag in CO2 increase is the fact that CO2 IS a greenhouse gas–the second most important in terms of its effect here on Earth. It is not reasonable that you could dump gigatons of carbon into the atmosphere (either as part of a natural feedback or via anthropogenic activity) and expect it to have no effect. As another indication that such feedbacks have been important in amplifying solar variability as a driver of climate, consider the article on Milankovitch cycles: http://en.wikipedia.org/wiki/Milankovitch_cycles
The gist is that solar forcing is not sufficient to explain the effects seen, so other mechanisms must also be important in amplifying solar effects–best candidate: natural greenhouse gas emissions as Earth heats up.
In the current case, we know things are different–CO2 is leading temperature, and we know it’s driven by anthropogenic sources of fossil carbon (due to the isotopic abundances). The question is what happens when we get to the point where we trigger the feedbacks that release the natural stores of CO2 and CH4.
And I 100% agree that the truth will win in this case. In scientific cirles, it already has. Unfortunately, the question is whether we will convince policy makers to respond in time. Decreasing carbon emissions will mean some very significant changes–requiring much higher energy efficiency for everything, diversifying sources of energy toward renewables and away from cheap, dirty coal. And it will mean doing it on a global scale, not just a national scale. For instance, shifting to compact fluorescent or solid state (LED) lighting represents a significant savings in energy (and money), but will take a lot of effort and up-front expense, time and effort. Meeting energy demands with either renewables or nuclear power will take decades. And the problem is that we do not know how long we have until natural ghg emissions kick in and render our efforts effectively meaningless.
So you see, this is not a simple matter–as in the case of evolution vs. creationism–where science can ignore the few contrarians and not care that a significant proportion of the population remain unconvinced. This is a situation where we have to act soon. The thing is that the answer will be obvious to our progeny, and they will likely judge us harshly for complacently gambling with their future.
Uh oh, now I have to put on my contrarian hat and disagree with Ray’s comment:
“this is not a simple matter–as in the case of evolution vs. creationism–where science can ignore the few contrarians and not care that a significant proportion of the population remain unconvinced.” (This comment aside, I usually find Ray’s posts very informative)
We biologist DO care, and are just as frustrated (perhaps even more so?) over that issue as the scientific community (and others) is over the AGW skepticism/denial. When local communities start changing school science curriculum standards and requiring disclaimers in science textbooks to undermine the teaching of evolution, and when our students claim passionately that evolution is a myth, the impact is felt immediately by those of us who teach biology.
Hi Chuck, Let me quickly backpedal. I have been known to tilt at the occasional fundamentalist Young-Earth Creationist (YEC) windmill myself. The difference here is that the YECs probably do not pose a direct threat to the infrasturcture of civilization, whereas climate change could well do so. So, while I would have no objection to YECs teaching creationism in their private schools, I would object to the contrarian point of view being passed off as if it were actual Earth Science. The difference is that I can oppose the contrarians without being in violation of the Constitution’s establishment clause. Having said this, I share your frustration every time I read the news and hear about these morons taking a fieldtrip to the Grand Canyon and saying it was created in a matter of minutes during “The Flood”.
“No Phil. You don’t understand how science works. In public debates, truth is utterly unverifiable because one side can make up fake facts to refute actual facts…it is a fool’s game”
I understand very well how science works – but I cant say the same for politics or changing public opinion :)
Public discussion may expose â��fake factsâ�� as such, but at the moment they just do the rounds on the Internet or pop up on Channel 4. People have every right to be able to ask questions because we will be paying higher tax bills and many people in the developing world are to be denied the chance we had to develop.
Bringing in the evolution debate is irrelevant – that is an argument between two different mind sets that will never and can never agree. You could say it’s a battle between the irrational and rational. The argument about GW should be a discussion between scientists who disagree but could agree and indeed will agree when the long terms facts are available.
You say – “a lot of very sensible people are feeling we are being manipulated into a belief”
Too true. But it’s not the climate scientists who are doing the manipulating.
Since you feel you’re being manipulated, you might look at what industry is saying. More and more are publicly stating that climate change is real, human caused, and emissions must be reduced. Even that bastion of anti-regulation conservatism, the U. S. auto industry, in recent testimony before Congress, agreed that regulations to reduce greenhouse gases are needed. The same thing is being demanded by many large industries in the U. S. including many power companies and oil companies. The insurance industry has long recognized the increased risk climate change poses to their industry and has begun to change how they insure – or, rather, who they will no longer insure. Are these powerful industries all being manipulated by a bunch of geeky climate scientists (no offense folks)? Or do they know what they’re doing and are acting in their economic best interest?
Don’t take my word for it. Go to the industry websites. Most of them have a link to climate change.
I disagree. The do think the YECs are a threat to the infrastructure of civilization. In order to be a YEC, you have to deny all science – not just evolution, not just biology – but geology, astronomy, physics, etc. I don’t think we can overestimate the damage done to our society by the anti-science/poor science education that has been fostered by certain fundamentalists for over a generation. A public that is largely science illiterate, is easy to manipulate.
No, I’m serious. For many reasons. For one, if we act to mitigate GW, when it is not happening, we save lots of money & strengthen the economy (see http://www.natcap.org for some inspiration). However, if we fail to mitigate GW & it really is happening, it would be a long played out world disaster. So, unlike scientists who must strive to avoid false positives (requiring high confidence to make claims, so as to protect their reputations & not become the boy who called wolf), people concerned about life on earth (you’d think) would be striving to avoid a false negative (fiddling while the world burns) on this issue.
Another reason it’s okay to overestimate AGW from what science is now telling us, is that as the science reports come in year after year, on the whole the trend is “GW’s worse than we thought” (I’ve been following it for 17 years, and that’s the sense I have). So, if we over-estimate the problem, eventually the science will likely catch up with us, and we’ll eventually be right. For just one instance, they underestimated the melting of the Greenland icesheets. However, I’d never gloat, and I sincerely wish I’m wrong on this.
Another reason is that there are lots of uncertainties (as contrarians like to point out), and those uncertainties cut both ways. I think it’s hard to quanitify just when and to what extent GHGs will be released from melting permafrost and ocean clathrates (though we do know that heat melts ice), or to what extent nature will slow down in absorbing GHGs given the heating going on. Or at what point and to what extent there will be forest fires due to the heating, drying out, and changed wind situations from AGW, causing more GHG releases and reducing sinks.
So, yes, to be on the safe side, it’s better to overestimate AGW.
Comment by Lynn Vincentnathan — 20 Mar 2007 @ 8:21 PM
Elizabeth, I think the most we can hope for is to keep the forces of anti-science–be they creationist or denialist–to a tiny and powerless, but hopefully not-too-disgruntled minority. To date we have mostly done that with the YECs. Yes, they occasionally rear their heads in Kansas or Pennsylvania, but nowhere has a school board that imposed creationist standards been re-elected. Where they become dangerous is as part of a coalition–as this magnifies the strength of their small numbers (yes, I know more people say they believe in angels than believe in Angels, but most of these folks can’t name all 4 gospels, either).
The situation is very different wrt climate change. There is a very good chance that the anti-science types will succeed in keeping us from addressing climate change until all we can do is watch it happen. It is the degree of the threat that is greater
RE #123, I sort of agree with you Phil. It looks like we’re going to need taxes, policies, and laws to get people & businesses to reduce their GHGs. Too bad, they could have done so by factor 4 or even factor 10 in some cases (see http://www.natcap.org ) while saving money. But OH NO, they had to drag their heels kicking and screaming like brats for nearly 20 years since we’ve come to understand this problem, and now the hour is growing very late indeed. No more leeway. The do-badders will have to be forced to do good. Afterall, we can’t have people going around ruining the world for everyone else. Too bad indeed. And I blame it ALL on the contrarians and denialists!
Comment by Lynn Vincentnathan — 20 Mar 2007 @ 9:52 PM
Does invoking Ming Dynasty Annals count as Junk Science ?
“.. as the science reports come in year after year, on the whole the trend is “GW’s worse than we thought”
Is this really true? If so, in the past the theory/scientists make predictions, then as time goes by you find that it is consistantly “worse than we thought”.
This would indicated that your theory has never yet understood the climate well enough to make any predications that work.
I “sort of” completely and utterly dissagree with you Lynn.
The evolution debate is perfectly relevant for the AGW discussion, because concerning climate change, it is also a clash between different belief systems. The pure scientific discussions are about “unimportant” details, not about the red line of what’s happening. Someone who is brought up with a belief in unlimited growth, unlimited technical capabilities, freerider-ship, externalizing of costs, nature is here to be used for mankind, taxes are evil, the higher the GDP, the better we’re off, disregard for the wellbeing of others, putting individual gain over communal gain, etc.; someone with such an outlook on life will have as hard of a time to accept the reality of AGW as a creationist has to accept the reality of evolution. Their belief system prohibits it.
Science happens to back up those with a different belief system. Reality (as approached by the conclusions of scientific endeavour) doesn’t clash with their belief system, so they can accept reality a lot better than those whoe belief system doesn’t allow for such a reality.
Both the climate change and the evolution “debate” should be a discussion between scientists, but neither are. In both fields, more than enough information is available to make an informed decision, but large groups of people block out this information since it doesn’t match their worldview. And of course there’re still enough missing links and uncertainties in the science that they try to (ab)use to back up their predetermined and unchangeable position.
Re 129, Personally with Peak Oil and Gas not that far off now (10 to 20 years) then the price of these fuels will rocket which will demand alternatives as a response. Global Warming is telling us to look into them now and hence maybe its a win win situation all round this time unless of course no alternatives are viable enough to replace fossil fuels as their energy denisty is very great relative to other so called sustainable energy sources.
This is why governments should be drawing up plans for large scale R&D plans for viable alternative fuels. Only coal is around in abundance and in many countries (energy security) but I doubt that it will fill in for peak oil and gas as you need Oil and Gas to get the coal out of the ground.
The implicit comparison of Man-made-GW sceptics to creationists is interesting…
Surely, relatively rational people should be able to have a reasonable discussion. We can start from the very sensible statement that CO2 has an effect, then move to a discussion of how much that effect will be â�� itâ��s an argument of degree not kind.
To see sceptics in the same camp as creationists may make you feel stronger in *your* rational world view and less interested in listening to anyone else’s rational world view.
A discussion on the long term effects of CO2 can be a scientific one. What to do about it is a political discussion and if you believe in democracy then people have to decide.
Monday we learned or should have, that you must change the policy to fit the science, not the other way around. Today, we will learn more about why the policy must be changed.
This morning at 930am EDT and later today at 230pm EDT former VP Al Gore will testify before the U.S. House and Senate on global warming. The hearings will air on C-SPAN3 live and on C-SPAN radio as well as online (not certain about that) and will be shown delayed later today on one of the other C-SPAN channels. Maybe we will find out how green his house is. Heh, heh, heh.
In the interest of balance or perhaps comic relief, Danish economist Bjorn Lomborg will also appear. If the Republicans decide to act up again as in the case of Dr. Hansen’s appearance, Gore’s slide show may turn into a side show.
PhilC, In scientific circles, rational discussion should be based on the evidence. The so-called “skeptics” who claim that climate change is not occurring or that humans are playing no role in it have chosen not to deal in evidence, but rather to appeal to the nonexperts via the media. (For example, see the reference to warming on other planets/moons in Lindzen’s closing argument–an argument so specious and transparently false that it casts doubt on his bona fides.) In so doing, they have abandoned rational scientific discussion, and the tactics they have adopted are very like those of the creationists–attacking the established science while advancing no viable alternatives to it.
Now, I 100% agree there is lots of room to talk about how we deal with this issue. That is politics. The role of science here is to provide a conservative estimate of how long we have to act, the consequences if we do not act and the level of effort required to make a difference. In effect, this is what the community has been trying to do throught the IPCC process and other venues.
Re: 127. Lynn, I think that risk assessment provides the language you are looking for. In risk assessment, we estimate risk in different ways depending on the purpose we are trying to achieve. It is quite possible to overestimate risk if you are trying to design a robust system that will survive the likely stresses it will face. Thus is is perfectly acceptable to conservatively bound (that is, overestimate) risk if one is trying to ensure the system will work or if one is trying to assess whether a threat is significant. We are currently in the threat assessment stage, and it is fair to say we have established the significance of the threat. The next step is to shave away some of the conservatism in the estimate (eliminate some of the error in our overestimate) so that we can efficiently allocate resources to deal with the threat. Here, it is helpful to have both upper and lower bounds on the risk.
RE #141, “If it were as cost free as that group asserts, it’d be a no-brainer. Nobody bleievs it is,”
Well, anyway, we can start with the low-hanging fruit of cost-effective energy/resource conservation/efficiency, and my electric and other bills took nose-dives, while we actually increased our living standard. So, I know from experience that a typical American household can reduce their energy & resources by at least 1/3 (perhaps even more if they put some thought into it), while saving money AND maintaining their living standard. The same goes for businesses.
It is just pure wickedness and/or lack of information that prevents this. But since I’ve been trying to tell people about this for over 17 years, with no bites, I think it’s wickedness.
Comment by Lynn Vincentnathan — 21 Mar 2007 @ 11:21 AM
Many different types of estimates of consequences will be needed, depending on the purpose of the analysis. Given that we are working with a chaotic system, I would say that any possible outcome (e.g. past Earth climate) that doesn’t violate conservation of energy and is not inconsistent with the other known physics is a possibility, wouldn’t you. By those standards, I would say that the IPCC has been conservative indeed. By trying to keep their predictions to the near term, they are indeed focusing on the likely outcomes of climate change–not the worst case outcomes which would probably occur in later centuries of the warming epoch.
Climate change is certainly established as a credible threat, and expenditures to mitigate its effects are certainly justified at a level commensurate with the risks it proposes–conservatively in the trillions of dollars. Moreover, there are things we can do NOW at relatively low cost that will mitigate the problem and buy us more time. Forget Kyoto if you wish, it was an ill considered venture in that asked nations to act against their own immediate interests. But if you are going to forget Kyoto, replace it with something better, as complacency is never a good policy in the face of a credible threat.
Re #136, I did not say it was global warming telling us, not did I say that we were going to run out either so please stick to what I said. Global warming is forcing us to look into alternative energy means to fossil fuels but they are not going away anytime soon and yes part of a Governments strategic remit is to source and provide energy and protect its people and I would say that global warming and energy provision are part of that scheme. Oil companies are Oil companies, not energy companies although I am sure that they will become that.
Re #142 “we can start with the low-hanging fruit of cost-effective energy/resource conservation/efficiency, and my electric and other bills took nose-dives, while we actually increased our living standard. So, I know from experience that a typical American household can reduce their energy & resources by at least 1/3 (perhaps even more if they put some thought into it), while saving money AND maintaining their living standard. The same goes for businesses.”
Something I recently heard on UK radio 4′s “Today” illustrates why it’s not that simple. The item was about all the food bought and thrown away (there’s an AGW connection, as it mostly goes into landfills and generates methane). The programme monitored a volunteer for a while, and worked out her family was throwing away about Â£1000 (say $1800) worth of food a year. Her comment was something like: “That could have been holiday flights and the car hire at the other end”. Same with cutting energy bills – for individuals or businesses. What will they do with the money saved? It may be something less harmful, but there’s no guarantee. Try googling “Khazzoom-Brookes postulate”. Monbiot (I think) states this thus: “As energy efficiency improves, people can afford more energy-intensive solutions, so improvements in energy efficiency can actually lead to more consumption, not less.”
Reality -you are dealing with humans. Lynn, as you point out , we could all cut our electricity bills by a significant amount by simple energy conservations .Yet, we typicaly don’t. even if you had no opinion on GW this would appear to make sense.
RE #145, “Something I recently heard on UK radio 4′s “Today” illustrates why it’s not that simple…”
Of course, it may be more difficult for Europeans to reduce their GHGs, since they only emit half the GHGs as the typical American in the first place.
And I’m glad you mentioned food spoilage. We have a SunFrost frig ( http://www.sunfrost.com ), which we bought in 1991. It uses 1/10 the electricity of a regular frig & paid its $2500 cost in about 16 years, both from energy savings AND less food spoilage. Food just does not spoil (except ginger root, which we now keep in the freezer), and we hardly throw anything away. For instance, cilantro lasts for 2+ weeks, and even then it just wilts, but doesn’t go bad!
When you seek ye first the kingdom of righteousness, all things are added unto you. Be not afraid. And think of all the other problems that get reduced: acid rain, local pollution, etc.
The first thing we did with our savings was pay off all our debts. Now we’re saving for retirement, and donating more to those poor people Crichton & Lomborg are so concerned about. And it’s only right we do so, since we’re destroying their subsistence through our GHG emissions, so it’s not charity but reparation.
Comment by Lynn Vincentnathan — 21 Mar 2007 @ 1:34 PM
re #147 “The first thing we did with our savings was pay off all our debts. Now we’re saving for retirement, and donating more to those poor people Crichton & Lomborg are so concerned about. And it’s only right we do so, since we’re destroying their subsistence through our GHG emissions, so it’s not charity but reparation.”
That’s great, and no personal criticism was intended. My point is simply that energy efficiency is nothing like a panacea, and can even make things worse – a major reason I don’t think the “Natural Capitalism” solution will work. Similarly, cheap biofuels, or hydrogen, could force down gasoline prices and so increase demand. You have to force the price of GHG-intensive activities up, or introduce rationing, to be confident of pushing things in the right direction.
#148, we also moved to Texas, where we got onto Green Mountain 100% wind energy, and if we could get an electric car (or even a plug-in hybrid) then we could drive on the wind. We also moved to a place close to work, & my husband & I carpool.
There’s plenty of things to do, once people put their mind to it. And I esp like the big things, like the SunFrost, since we just plug it in and forget it, while it silently (they are extremely quiet) uses a tiny fraction of the electricity needed by other models.
Even a frig thermometer can save, say, 5% of the energy (set frig at 42 degrees F; freezer at 2 to 5 degrees F), and they only cost $2.
We Americans of today are totally profligate. Talk to people who were here during WWII & how they recycled and saved. My grandmother, who was well off, used to save string.
Comment by Lynn Vincentnathan — 21 Mar 2007 @ 3:09 PM
It would seem that if one has more trust in the private sector than in government then one might consider that the one business who’s job is assessing risk is concerned about the effects of global warming.
And as far as oil companies, even Exxon recognizes global warming is real and “”the risks to society and ecosystems could prove to be significant, so despite the areas of uncertainty that do exist, it is prudent to develop and implement strategies that address the risks.
“A lot of those recommendations are more regulations and more taxation,” said former House Speaker Dennis Hastert, R-Ill., though he added that he agrees with Gore that the scientific debate on climate change is over. “I think we can find answers to use the coal energy, to use the natural gas we have.”
Re #151: [We Americans of today are totally profligate. Talk to people who were here during WWII & how they recycled and saved. My grandmother, who was well off, used to save string.]
To a large extent this is just cultural conditioning. Mainstream western culture has had the media delivering a stream of messages implicitly equating status with how much a person’s able to waste, to the extent that it seems to have almost become a potlatch culture – except of course that a true potlatch involves giving things away, while this culture stores its excess goods in closets and garages.
Still, there are subcultures that have rejected this conditioning, so it’s hardly innate. Change the messages, give people strong enough reasons to change, and many of them will do so. For the rest: well, let’s replace a bunch of existing taxes with a carbon tax, and let them pay :-)
Re 152, I doubt that private companies would bother unless Governments were considering legislation to force private companies to operate in a different manner. Only Government can tackle climate change due to its global nature.
Look at the currently available operations going on to lower CO2 emissions. Strategically it is a mess from what I can tell, a hodge podge of collective and individual efforts to ultimately make money from creating low CO2 technologies. I currenly see no coherent strategy, I am sure that it will come, Condi Rice was in Europe yesterday making all the right noises about it.
Maybe we can get some global cooperation and a strategy for viable low CO2 energy sources because as it stands at the moment no one knows if biofuels can replace Oil, if wind, wave, solar and pv can replace coal and gas etc or indeed if we can scrub coal clean on its carbon.
I’ve been browsing this thread and have noticed talk about oil/gas reserves running low.
In David Archer’s, “Fate of fossil fuel CO2 in geologic time.” http://geosci.uchicago.edu/~archer/reprints/archer.ms.fate_co2.pdf Reserves of extractable fossil fuels are said to be of the order of 5Gton Carbon. Most of this is coal. The other stuff I’ve read supports the view that there are at least several Gtons Carbon of extractable coal alone.
Surely issues around finite reserves of fossil fuels are not a major factor in terms of limiting CO2 emissions. Because for coal, we seem to have enough to make human emissions so far no more than a drop in the ocean. And when we consider the issue of ocean uptake being impacted by warming and ocean pH. Those emissions could have a greater impact on atmospheric concentrations in the future.
In short I just keep being drawn back to the conclusion that in terms of ‘energy returned on energy invested’ coal will remain the most competitive energy source. So it will simply take over from oil and gas as the mainstay power source for the 21st century, undercutting solar and other options. Fluidity of investment in the world economic system could easily make control of emissions practically unattainable. And that’s in a world with a population increasing to the 9-10Bn level, with a greater percentage of that population living carbon intensive lifestyles.
In the wake of this mockumentary I’ve been on messageboards dealing with the nonsense it’s lead to. It seems to me that the denialist fringe is now being relegated to the same level as the various incoherent conspiracy theories rampant on the ‘net. When they are driven to the sort of nonsense in GW Swindle and are unable to defend their position without the first recourse to insult, they know they’ve lost.
The contrarists seem to me to have been crushed by the evidence. But the real battle, to stir actual action is a far greater task. Nobody I know personally, apart from myself, has taken steps to reduce their carbon (and other impacts) footprint (and I don’t even have children of my own). Yet nobody I know really doubts the reality – like Marcus Brigstock implies – here in the UK we’re experiencing noticeably warmer weather.
Re #150 “[[Similarly, cheap biofuels, or hydrogen, could force down gasoline prices and so increase demand. ]]
The price of a commodity dropping because demand is lower is not the same as the price dropping because supply is higher.”
Actually I wasn’t meaning either – rather, the price dropping because a new alternative product enters the market. I should have spelled this out. At least if the alternative were to be marketed by different companies, the oil majors would be motivated to drop gasoline prices in order to dissuade people from switching to ethanol, hydrogen-fuelled or electric vehicles. If this happened, gasoline demand, and use, could rise.
Re #154. I certainly agree we need action at all levels.
Whether one is a denialist or part of the concensus of scientists saying global warming is not only real, it is most definitely caused by excess CO2 in the atmosphere, what does it hurt to consume less and conserve more energy? Sure oil companies make less money if we use less fuel and so they have a strong incentive to be denialists, but for the average person on the street, who is harmed by driving less and using renewable energy sources whenever possible.
“The contrarists seem to me to have been crushed by the evidence”
What concrete evidence is there that any temperature rises are actually caused by human emissions of CO2 – even the IPPC report said it was (only) 90% sure. If there really is no doubt then why can’t they simply come out and say so.
Calling “the Great GW Scandle” a mockumentary is rather demeaning – it stated in fact that temperature changes precede CO2 levels. Now, there is apparently an explanation for this (rather convoluted to my reading) but this tv program was the first (that I’m aware of) to present this FACT.
The alternative theory of cosmic rays seems worth considering – we are constantly bombarded with them and they will be having some effect. These are perfectly plausible (though possibly wrong) ideas, they are not crackpot theories and they have enough merit to be presented to the public. To dismiss them out of hand shows a refusal or inability to look at this problem objectively.
True to form, the now show sketch was just a rant by someone who would not understand a graph if he had to, and yet he is allowed (even paid) to perform a 5 minute spot on national radio to slag off someone who is at least qualified to have an opinion about these matters. The BBC refuses any dissenting voices tv airtime but encourages the condescending attitude of just dismissing or laughing at them. Unfortunately, the standard of science reporting on the BBC has descending to such a trivial level now that we cannot expect anything better. Please name one serious science program that the network now produces (David Attenborough doesn’t count as science because there are no graphs in his excellent programs).
Phil, don’t mistake someone saying “global warming is … most definitely caused by excess CO2 in the atmosphere” for a claim that all of the current warming is caused by fossil fuel emission. Nobody’s saying that who understands the science.
It’s not a question of attributing the cause 1:1, all or nothing, independent of all other forcings.
It’s clear from the science that the excess CO2 is causing — and will continue to cause — an increase in the planet’s temperature til radiative equilibrium is reestablished. That’s considering all the other known forcings, the other gases, the loss of the ozone layer, the slight variability in the sun, the deep ocean circulation, the solubility of the various gases — you can and probably have read the whole list in the IPCC report.
Straw-man arguments are found on all sides of the political porkypine. Point them out, don’t fall into arguig with them — learn the science. The AIP history is quite helpful.
I do understand your point but would you agree that in the media, arguments are usually put forward by people who donâ��t understand (any) science – they tend to make exaggerated claims and if questioned tend to dismiss the questioner rather than address any meaningful issue â�� this leads to a shutting down of proper debate. Again, I make that point that our environment minister has stated the debate is over.
I can’t find the reference (but could if asked), but recently a UK climate researcher who is fully signed up to the Global Warming Theory received abuse simply because he dared to criticise the exaggerated claims being made.
In the public arena any real facts are being buried under a great deal of conflicting misinformation – and as the sceptical view barely gets a look in, would you agree that the majority of this misinformation is coming from the non-scientific believers? Note: I am talking here about tv, radio and newspapers – not discussions between scientists.
Re # 164
[In the public arena any real facts are being buried under a great deal of conflicting misinformation...]
In the U.S., at least some of that misinformation seems to be coming from the White House:
Congress Probes Edits of Climate Reports
By Erik Stokstad
ScienceNOW Daily News
19 March 2007
WASHINGTON, D.C.–The House Committee on Oversight and Government Reform today released documents edited by political appointees in the Bush Administration that “appear to portray a systematic White House effort to minimize the significance of climate change,” according to committee staff. Current and former appointees who made the changes appeared today before the panel and testified that they were trying to introduce scientific uncertainty in the reports.
I recommend you focus on the science, read the papers, talk to your local library reference desk for copies of the journals that aren’t available free online, and check the claims against the footnotes.
Ask intelligent questions. Eric Raymond’s advice, written for new programmers, is pertinent to anyone starting into a new area of science:
Smart questions avoid wasting time of the few scientists who _have_ a bit of time to talk to the rest of us and can do so in terms we can understand.
The trolls intend to waste their time, and steal everyone’s attention — making it harder for those of us who want to understand this to learn.
The AIP page is quite good for the background needed to understand the more recent work.
The IPCC is the best statement of what’s understood, as of the date its comments closed; look at the Commenters and Other list on the right side of the main page for home page links to publications that may expand on that.
Re #161: [...it stated in fact that temperature changes precede CO2 levels. Now, there is apparently an explanation for this (rather convoluted to my reading) but this tv program was the first (that I'm aware of) to present this FACT.]
The key words there are “that I’m aware of”. The problem is that, as with any speciality, there are questions that those in the field have discussed and answered long ago, so that they become part of the “well, obviously everybody knows that” background.
Of course to someone new, it’s not immediately obvious, but to leap from your not knowing to a conclusion that it’s being deliberately hidden… well, to me that says you’re coming in with your mind already made up.
PhilC, first, I don’t trust any information about the science that comes from a nonscientific source. That includes Al Gore, and it includes Rush Limbaugh (though Gore certainly gets closer than Rush). Second, if anyone tells you they know exactly what will happen, they are either uninformed or lying. Climate is a chaotic system–that means it will not respond the same way to the same perturbation repeatedly. It may be that by adding energy to the system, we merely wind up with (on average) a warmer, maybe somewhat wetter, and certainly more variable world. However, it may be that we wind up with a highly variable climate, where year-to-year predictions (e.g. when rains fall, when the first frost comes, etc) are very, very difficult.
People tend to think in terms of disasters they have experienced before–floods, hurricanes, droughts…. It is true, we cannot say whether these disasters would necessarily be worse due to climate change. However, I think if you asked some Aussie farmers, they’d put up with the occasional flood if they could just predict when it will rain next year.
Humans are amazingly adaptable–we can probably prepare for any conditions we can anticipate. And maybe we can adapt to harsh conditions, but harsh and rapidly changing conditions will be very challenging.
Right now, because people are coming to terms with the fact that climate change is a real threat, and because we cannot predict how it will play out, people tend to project their fears onto it. Those who fear government power project their fears of a power grab by government. Those who fear disasters project their favorite disaster. The reality could in fact be worse, or not–we just don’t know.
RE: 173. So, Tom, why are you so obsessed with what Al Gore says. His opinion is as irrelevant to the scientific consensus as is Rush Limbaugh’s–he just seems to have gotten a lot closer to the actual science than Rush.
Re #173 Your normal body temperature is 98.6? Perhaps, but very possibly not:
The 98.6Â° F â��normalâ�� benchmark for body temperature comes to us from Dr. Carl Wunderlich, a 19th-century German physician who collected and analyzed over a million armpit temperatures for 25,000 patients. Some of Wunderlichâ��s observations have stood up over time, but his definition of normal has been debunked, says the April issue of the Harvard Health Letter. A study published years ago in the Journal of the American Medical Association found the average normal temperature for adults to be 98.2Â°, not 98.6Â°, and replaced the 100.4Â° fever mark with fever thresholds based on the time of day. http://www.health.harvard.edu/press_releases/normal_body_temperature.htm
In this case, scientists and medical doctors have no doubt contributed to perpetuating this myth (however harmless it is). In case you’re wondering, the source of the discrepancy was rounding error when converting between the Fahrenheit and Celsius scales.
I don’t think there is a “normal” temperature for the earth. One could define it as the average temperature for the last few thousand years, which seems to be about 14 deg.C (57.2 deg.F). But before that, its average temperature showed large swings — probably about 5 deg.C (9 deg.F) difference between full-on glaciation (usually thought of as “ice age” conditions) and interglacial (like now).
But environmental health for the planet is not the same as medical health for an individual. Humans are set to be at a particular temperature — 98.6 deg.F (37 deg.C). But for the planet, “healthy” means stable. If earth’s temperature changes, living things will adapt, evolving to thrive in a different temperature or migrating to a warmer/colder location. As long as temperature is stable, the ecosystem can thrive. But when temperature changes, it can bring trouble. The real problem is that it can take a very long time for ecosystems to adapt; when temperature changes rapidly it spells real trouble for living things.
The change from glacial to interglacial is about 5 deg.C, and this typically takes 5,000 years or more, so the rate of change is around 0.001 deg.C/year or less. The rate of change now is around 0.02 deg.C/year, 20 times faster. And that spells trouble with a capital “T”.
RE #172: It will be getting warmer and that does not bode well for earths subsystems in the main. You say it is a chaotic system but which system are you talking about exactly? I suggest it is a complex system that if perturbed far enough from equilibrium then it could go chaotic, however perturbing the climate enough for chaos to set in system wide would take a lot of additional energy as the interia is so high due to the sheer size of the system in question.
So come on PhilC, stop using pseudo scientific babble that you seem to like so much and to some real science. Ask RC what sort of system earth is and sure they will tell you it is linear mainly, the non linear couplings might only be triggered after very large scale perturbations have been experienced and that means we most likely will not cause that sort of system to be.
“In the public arena any real facts are being buried under a great deal of conflicting misinformation – and as the sceptical view barely gets a look in, would you agree that the majority of this misinformation is coming from the non-scientific believers?”
Yes from believers of the myth that global warming is a myth. All of the misinformation comes from this group and it is funded by industry.
Going back to one point raised in the Channel 4 program. Sceptics are often told that we have too little scientific understanding to criticise the theory.
But how many who laugh off the proposed cosmic ray theory have any knowledge on how cosmic rays effect the earth. Someone spending the last 20 years looking at CO2 levels would have had no time to develop sufficient knowledge to even question the theory. And yet people with no qualification or experience in this field tell us the theory is crackers â�� double standards?
If you dismiss this theory try asking if your only real objection is along the lines of â��it must be crackers because everyone knows global warming is trueâ��
I have no idea if/how cosmic rays effect cloud cover, but much stranger ideas have turned out to be true
plate tectonics (crackers),
dinosours wiped out by meteor (crackers)
quantum mechanics (seriously crackers)
man from monkeys (they thought that was crackers â�� some still do :) )
I fully accept that equally strange ideas were just plain wrong but you shouldnâ��t dismiss or accept a theory just because it sounds odd
So until someone qualified can tell me why we can ignore cosmic rays I will consider it a possible explanation â�� just as I do for Co2 levels
Re #183: PhilC — Sorry, I don’t know where to find it. The comments in the Swindled thread or in the What triggers ice ages thread went over this matter fairly thoroughly. I suggest reading those and then, if that’s not enough, doing some web trawling. (As I recall, this data comes from a Climax, Colorado site.)
Comment by David B. Benson — 22 Mar 2007 @ 5:17 PM
Remember cosmic rays were discovered less than a century ago, and the first detectors were painstakingly hand carried to mountaintops, which doesn’t get you a longterm consistent data set. Only recently have large scale permanent detectors been operating. You’ll find several besides the one I pointed to in an earlier link.
Again I know nothing about this, I’m just showing how to use the search tools. Look for good science info to evaluate. Beware bogus PR sites, they’ll show up too, but they lack footnotes to good science publications.
Note correlation is not causation; consider what mechanism might explain any correlation remarked on, and how likely the result described is to be a chance occurrence (for example murder rates correlate, in some studies — but is this found in say one study in twenty, or more frequently?).
Re #185: PhilC — I recommend reading the Cosmoclimatology thread, down a few, to obtain a RealClimate perspective on cosmic rays. (Sorry I didn’t remember where it was earlier.)
Comment by David B. Benson — 22 Mar 2007 @ 6:01 PM
Re 181. Phil C. I am not a specialist in studying galactic cosmic rays, but I and my colleagues monitor them on a regular basis because we look at bit flips in memories on satellites. I have also had occasion to look at the cosmic ray data from the last 25 years taken by GOES and other satellite series with long histories. Guess what–GCR fluxes are not changing much except for the modulation of the solar cycle. The first criterion for any cause is that it must be present when the effect is present. There just isn’t enough change in GCR flux to make any difference in climate.
I have a lot of questions about the plots in Svensmark’s papers–how does he get his correlations for low clouds, for instance. But even if true these could be artifacts–a lot of things about solar behavior change with the solar cycle. Now it is true that a charged-particle track can provide nucleation sites for condensation if there are no other sites, but this is far from the case in general. Dust does just fine, as do aerosols, etc. GCR fluxes in space average only about 5 particles per square cm per second–tiny–and the showers reach their maximum well above 50000 feet, so why don’t clouds form there.
And even if this were a credible theory, there would still be the question of why CO2 did not have more of an effect on climate. GCR could influence climate only when the strike Earth–there’s no persistent effect as with CO2, and this warming trend is nothing if not persistent. Look, I’m someone who worries about cosmic rays for a living–but their influence on climate is not something I worry about.
Re #161: [...it stated in fact that temperature changes precede CO2 levels. Now, there is apparently an explanation for this (rather convoluted to my reading) but this tv program was the first (that I'm aware of) to present this FACT.]
This is a known thing (as James #170 pointed out), but it also raises a very problematic situation: the warming we humans are causing now, could, if it continues, cause nature to release GHGs, causing more warming, causing more GHG releases. We would be wise not to go near that threshhold. And I think the reason you don’t hear a lot of scientists harping on this very dangerous scenario is because it’s very hard to quantify or predict when this might happen. We do know that heat melts ice & that there lots of gigatons of carbon in ocean ice cages (clathrates) and in the permafrost.
Mark Lynas (SIX DEGREES) figures this may happen with 4C & 5C warming, which is within the projected bounds for this century, and probably even more likely within the next 2 centuries, if we don’t mitigate.
It would virtually mean extinction of a very large chunk of the world’s biota and great reduction of the human population (not to mention great material poverty).
So that fact that CO2 emissions follow warming is not something to feel good about.
Comment by Lynn Vincentnathan — 22 Mar 2007 @ 10:29 PM
Question regarding cosmic rays:
The CLIMAX Neutron monitor does not show any trend in GCR since the 50s. However, cosmic ray proponent Shaviv claims that the ion chamber data are more relevant for potential aerosol (and thus “hopefully” cloud) formation, because of the energies measured. And he claims that they do show a decreasing trend.
I have read here on RC that the two (or multiple) types of particles should agree with each other, and that neither side of the argument has an explanation for the fact that they do not. I understand that the CLIMAX neutron monitor is the longest time series, so therefore more suitable for a trend analysis. But is CLIMAX typically regarded as the “reference” measurement of cosmic rays? Are the trends in the ion chamber data statisticlly significant? Or are the ionchamber data Shaviv refers to rubbish to begin with?
IF there were a trend in cosmic rays and IF they had a large effect on climate, wouldn’t we see a 11 year oscillation in the temperature signal? And since the purported correlations between cosmic rays and cloudiness are strongest over the oceans, wouldn’t we see the strongest temperature increase over the oceans? Or would the heat capacity of the oceans dampen out the locally stronger radiative forcing? Would the cosmic ray-cloud theory result in a warming of the stratosphere, just as a direct increase in solar irradiance would?
With a performance like that, it is no wonder that the global warming protagonists prefer to call the science “settled” and avoid debate. Their weakness was clearly visible. Their position is about as water tight as pegboard.
Comment by Pierre Gosselin — 23 Mar 2007 @ 7:26 AM
[[What concrete evidence is there that any temperature rises are actually caused by human emissions of CO2 ]]
1. Tyndall in 1859 demonstrated that carbon dioxide absorbs infrared light.
2. Keeling et al. showed in the 1960s that atmospheric CO2 was rising sharply. That rise has continued.
3. Suess demonstrated in 1955 that the isotope signal of fossil fuel burnt CO2 was present in Earth’s atmosphere.
4. CO2 is now some 40% higher than before the industrial revolution started. No plausible source other than fossil fuel burning and deforestation exists.
For more, check the IPCC reports, or if you don’t like them, try Spencer Weart’s “The Discovery of Global Warming” (2003), which gives a nice overview of how the science developed. I believe it’s available free on the web somewhere.
[Response: It the first link under "Science Links" in our blogroll, or just go here. --mike]
“Mark Lynas (SIX DEGREES) figures this may happen with 4C & 5C warming, which is within the projected bounds for this century, and probably even more likely within the next 2 centuries, if we don’t mitigate.”
is this same (pie throwing) Mark Lynas who holds a degree in history and politics :) wikipedia
Re 193. Darrel, I have not perused the Climax and ion chamber results in detail, but I would be surprised if there were too statistically significant a difference between them. Moreover, the on-orbit data we have shows no change beyond the 11-yr solar cycle modulation. Svensmark et al. base their claim–as near as I can tell–on the correlation between cloud cover and the solar cycle. However, a lot changes with the solar cycle beyond the cosmic ray flux, so I regard this claim as a little suspect. I’m also unclear on exactly how they generate their low cloud cover data. Finally, clouds can both cool in the day and warm at night. Why would one effect be expected to dominate?
So, on the one hand we are being asked to choose between one mechanism that is little understood beyond a vague handwaving level (cosmic rays) and a mechanism with a venerable history and lots of solid research behind it. Even if we were to choose the more vague of the mechanisms, we’d have to explain why all the previous research was wrong. Good luck with that.
Re 194. A public debate does not lend itself to truth squadding–and when one side is willing to play fast and loose with the truth (c.f. Lindzen’s allegations of extraterrestrial warming on Mars, Pluto…), they can appear to be more convincing. This is why science is not decided by public debate, but rather by consensus. You really should look into it–science I mean–it works pretty darn well.
The global annual mean surface air temperature changes can be obtained in graphical and tabular formats at the NASA GISS site. NASA GISS I’m sure would have readily agreed to their use in Durkin’s programme. One wonders why he didn’t use them.
You could do the comparison yourself, rather than rely on someone else’s possibly jaundiced view. Durkin’s effort is referenced in the “Swindled” OP (though I think this is one they modified slightly when retransmitting it on a C4 sister channel), and there is ample discussion over at Stoat on this issue (see RH margin for link).
I wouldn’t want to influence your judgment overly, but the graphics splitting out the latidunal variations are also instructive (I think).
re: 196 and 202. “Proof” is a mathematical concept. Science research does not aim for “proof”. This is a fundamental concept. It draws conclusions based upon the hypotheses, data, research, theories that explain data, repeatable experiments to test theories, and peer review. It is called the scientific method. Which AGW research has followed.
I would be happier if the evidence was enough to convince the same experts putting forward the consensus.
the ipcc report scientists were only willing to stand by a 90% probability that man-made co2 is causing global warming. I understand that a good scientist should avoid absolutes so if they had said 99% I would at least think they were sure.
After all this time,money and effort the experts still say there is a 10% chance that man-made co2 is NOT causing global warming
Can you imagine an engineer saying their new plane was 90% certain to stay up?
Re 205: Thats different and you know it. Planes do crash and hence the engineer might say it but he could not mean it and they would know that to. Everyone takes a risk flying even though that risk is small.
Aircraft are human made, engineered but climate is natural and hence natural variability plays its part, 90% certainty is stated because nothing is known with absoulte certainty, there is always an error factor. Complex systems has sensitivity to initial conditions issues and you cannot measure to infinite precision and to infinite space, ie not 100% accuracy but the statistics (balance of probability) make the assertion clear enough.
I’m sightly confused as to where this 90% figure comes from (is it the 4th SPM?) and to what it refers. Can you clarify please?
The SPM mentions:
90% uncertainty intervals unless stated otherwise, i.e., there is an estimated 5% likelihood that the value could be above the range given in square brackets and 5% likelihood that the value could be below that range.
So they are just giving the limits/likely error on a measurement or a forecast.
And then they use the following terms at various points:
Virtually certain > 99% probability of occurrence, Extremely likely > 95%, Very likely > 90%, Likely > 66%, More likely than not > 50%, Unlikely < 33%, Very unlikely < 10%, Extremely unlikely < 5%.
Re #203 [["Proof" is a mathematical concept. Science research does not aim for "proof".]]
Depends what scientific research you’re talking about. Much of science, contrary to what you read in simplistic treatments of philosophy of science, is not about general laws, or experiments. For example, it was long hypothesized that marsupials had once lived in Antarctica (because they live in Australia and South America, thought once to have been joined via Antarctica). Lo and behold, Antarctic fossils of marsupials were eventually found – proof that they once lived there. Of course you could say – well, maybe the fossils aren’t really of marsupials, or got there in some other way. But by the same token, many mathematical proofs (e.g. of the 4-colour theorem or Fermat’s last theorem) are so complicated there may well be errors in them. However, the main point of my question was that I suspected PhilC wouldn’t specify what would satisfy his doubts – as indeed, he hasn’t. The invitation for him to do so remains open.
Philc — which pointers to the incorrect graphs have you already read? There are two threads here, and somewhat over ten thousand hits on Google about the answer to that question.
It’s a bit hard to know where to begin, answering your questions.
Tell us where to start by telling us the source for what you currently know, please?
If you read it here and are having trouble understanding it, that’s one thing; if you followed a pointer from here to another site and aren’t understanding it, that’s another; if you found your info elsewhere and came here to ask about it — where did you get it?
Else we’re guessing in the dark about what sort of anwer will be helpful to you. Waste of time.
Re #198: [So, on the one hand we are being asked to choose between one mechanism that is little understood beyond a vague handwaving level (cosmic rays) and a mechanism with a venerable history and lots of solid research behind it.]
Remember, though, that it’s not a matter of “choosing between”, since AGW theory is not an attempt to explain observed warming, but a prediction (originally made long before any warming was observed) that adding CO2 will cause an increase in temperature.
Even if the GCR proponents could find strong supporting evidence for their theory, it would not invalidate anything related to CO2. Like aerosols, changes in solar output, and the occasional volcano, it’d be just one more factor to be added to climate models.
PhilC, can you imagine an engineer saying that a plane is 90% certain to crash and people still be willing to board? Not me.
Now I’m not sure where the 90% is coming from, but I think it stems mainly from the probablity distribution of model results (correct me if I’m wrong). I am not sure that it means that the scientific consensus is that there is a 10% chance of GHG not having any effect on climate at all. Actually, I’m pretty sure it doesn’t. I would think that most climate scientists would estimate such a chance as being much smaller. Also, take into account that in the language of scientists, 90% certainty is equivalent to “absolutely sure” for most non-scientists.
If the warming continues, only 5% and eventually only 1% of the model output would be consistent with GHG not havning an effect on climate. I don’t want to live in a world where that 99% certainty is reached, and neither will you or anyone else. But that is what we’re heading for if you want to wait for “proof”.
however, in the UK media – words like proof and certainty are used about the GWT with such frequency and force but when you start digging in you find large uncertainties about possible outcomes. Many supporters of the theory seem happy to accept these huge uncertainties just as long as the theory remains the concensus view, to many skeptics it seems far too wide open.
#197, yes, the same Mark Lynas. His father was a geologist studying glaciers in Peru, where Mark lived as a child. Mark went back there decades later and saw that the glacier had melted substantially. He also documented harms from global warming occuring around the world right now in his HIGH TIDE.
You have to understand that Lomborg was saying we shouldn’t mitigate global warming, Mark (a young man with more to lose from GW than us old fogeys) got mad enough to throw that pie. Maybe in a few years there will be lots of college & high school students throwing pies or worse at us old folks who keep on saying we shouldn’t mitigate. It’s their future we are harming. And that’s not nice. In fact, that’s worse than pie-throwing!
Comment by Lynn Vincentnathan — 23 Mar 2007 @ 11:48 AM
Still trying to fix the blockquote problem
Hope that does it.
Comment by Lynn Vincentnathan — 23 Mar 2007 @ 1:24 PM
You ought to see how the media here in Germany treat the science. They consistently call the activity of reducing man-made CO2 emmissions “Klimaschutz”, which literally means: climate protection. Can anyone explain to me how one goes about protecting the climate? Does this have anything to do with protecting the temperature, humditiy or windspeed?
Clearly this incorrect use of terminology demonstrates the utter incompetence of the media in handling or communicating the science at even the most basic levels. Is it any wonder that the position of the man-made global warming side isn’t taken as seriously as it probably should be? Incorrect use of terminology immediately raises suspicions. Can someone who keeps screwing up the basic terminology be believed? I don’t think so. If the man-made global warming side wishes to have any hope of convincing the world, then they’d better do 2 things: 1) improve the quality of their scientific arguments and 2) improve how to comunicate them.
Now if you don’t mind, I’m going to go and protect my blood alcohol content with a few Krombachers.
Comment by Pierre Gosselin — 23 Mar 2007 @ 1:38 PM
…and 90 % sure that man is causing what portion of it??
Re “…and 90 % sure that man is causing what portion of it??”
The way I see it is that if man is causing only a fraction of the warming, that’s even worse news (assuming something else is causing the rest).
Since we cannot control the sun or whatever else that’s causing the warming, it just means we have to reduce our GHGs all the more to offset not only our own part, but also the part caused by other forces. So either way, we have to reduce our GHG, only we have to reduce even further, if nature is also contributing.
Comment by Lynn Vincentnathan — 23 Mar 2007 @ 3:07 PM
….All values are shown as a change from pre-industrial conditions.
* Total radiative forcing from the sum of all human activities is a warming force of about +1.6 watts/m2
* Radiative forcing from an increase of solar intensity since 1750 is about +0.12 watts/m2
* Radiative forcing from carbon dioxide, methane, and nitrous oxide combined is very likely (>90%) increasing more quickly during the current era (1750-present) than at any other time in the last 10,000 years.
Pierre, on any important issue one should be suspicious of what the media says, and do some homework for one’s self. I am certain that if you read the IPCC SPM you will not find the phrase “climate protection” anywhere.
As far as the media goes, if you are to believe them there is a raging debate over global warming going on in the scientific community when in fact this is not the case.
I think both sides would agree that the media could do a much better job of reporting (though for different reasons I’m sure) so the lesson is that if you really want to know about something you will have to read some scientific books and articles outside of the popular press.
[[If the man-made global warming side wishes to have any hope of convincing the world, then they'd better do 2 things: 1) improve the quality of their scientific arguments and 2) improve how to comunicate them.]]
Point 2 has some validity to it, but point 1 is utterly bogus and just shows your lack of familiarity with the relevant science.
“You have to understand that Lomborg was saying we shouldn’t mitigate global warming,”
as I understand it Lomborg’s is saying that we can’t mitigate it enough to justify the huge expense using money that would be far better used to tackle humanitarian issues over which there is no doubt at all.
Activists such as Mark Lynas write books using the worst possible predications, give them emotive titles and are exactly the kind of supporters you dont need on your side.
this is what I mean by the ipcc saying “90%”
Global climate change is “very likely” to have a human cause, an influential group of scientists has concluded.
the panel concluded that it was at least 90% certain that human emissions of greenhouse gases rather than natural variations are warming the planet’s surface.
Having looked at the so-called ‘fake’ graph in TGGWS I accept that it may not be completely accurate but any differences with the official graph do nothing to take away from the conculsions drawn in the program. (I know realclimate has an explanation for the cooling period after the war)
Describing this as a ‘fake’ is like calling someone a lier becuase they included a spelling mistake in a paper
“so I still ask – why is the ipcc consensus of scientists, no less, unable to come out with a categorical statement on this fundamental issue?”
Because they are scientists and when you are dealing with theories scientists rarely if ever make categorical statements because all theories are incomplete. It is always a mater of approximations to reality. (Even our eyes only give us an approximation to reality, we can’t see infrared). And if they made a categorical statement about the cause of global the skeptics would be all over them in a nanosecond, because a categorical statement about the cause of global warming would be incorrect.
So instead they are honest and say what the evidence and their highly sophisticated models that are run on supercomputers tell them and give it a 90% probability, which in most peoples books is a high probability.
Yes, there’s a chance they could be wrong, but it is a low chance. The skeptics remind me of that dumb or dumber movie where the dumb guy asks the beautiful girl if there is chance that she will go out with him, she rolls her eyes and says, “yeah, 1 in a million…” and the dumb guy shouts, “YES!!! THEN THERE’S A CHANCE!”
I’m sorry if you find this offensive, nothing personal, but get a grip, Phil.
PhilC, The 90% confidence that humans are causing climate change is what they call a Bayesian confidence–basically you poll a large group of experts and take the level that emerges as a consensus. Scientists are by nature conservative. I think most physicists would only give General Relativity about a 90% probability–maybe less.
The fact of the matter is that there is simply no other credible alternative to anthropogenic causation. No other cause has even roughly the right time dependence or produces the right distribution of effects.
I do risk mitigation for a living. If I faced a 90% risk of dire consequences, I know that the right thing to do is direct up to 90% of the potential cost incurred if the risk is realized. I’m curious how you would have us respond. I mean scientists are continually looking into alternative factors already to see if any are significant. They are checking their research and that of others already. They are working on possible solutions to the problem. What, in your opinion should we do differently.
The other question is what would it take to convince you that we are in fact changing the climate? What evidence is there that you are looking for that you haven’t seen?
If your objection to remediation of climate change stems from economic considerations, then your argument should be framed in those terms. Attacking what is really well understood science because you do not like its consequences is not a rational approach.
Sorry, you won’t get “concrete evidence” in a system as complex as climate, especially as we only have the one largescale experimental example. Your comment about looking at things objectively was interesting. In my recent foray onto the Channel4 MessageBoards I was once again amused by how my evidenced assertions did not meet with evidenced challenges. I sometimes throw in deliberate ‘errors’ when meeting that sort of response to test my opponent. None were picked up, those trumpeting support of the programme hadn’t even got their brains in gear.
I’m an ex-GWsceptic who started reading the science in Jan 2005, I’d had enough then to suspect I was badly wrong. I gave up using virtually all sites on the net, except realclimate and official sites because I was sick of being told by the usual bunch that such-and-such a paper said something, but when I read the paper it didn’t.
I’ve long since given up on the media.
Most of the contrarist blather centres on uncertainty, but it’s esentially a Straw Man. Carl Wunsch put it so much better than I could:
“The science of climate change remains incomplete. Some elements are based so firmly on well-understood principles, or on such clear observational records, that most scientists would agree that they are almost surely true (adding CO2 to the atmosphere is dangerous; sea level will continue to rise,…).
Other elements remain more uncertain, but we as scientists in our roles as informed citizens believe society should be deeply concerned about their possibility: a mid-western US megadrought in 100 years; melting of a large part of the Greenland ice sheet, among many other examples. ” http://ocean.mit.edu/~cwunsch/papersonline/responseto_channel4.htm
The real uncertainty has moved out of the realm of “Are we warming the planet?” into “What will this mean in terms of it’s future effects on our daily lives (in a practical sense)?”
Anyway, if you need more certainty, you can always just wait. This is an ongoing physical process and no matter how much obfuscation we non-experts are subjected to by the contrarist industry, it will continue.
Physical processes don’t give a hoot about public opinion.
Phil, if the overwhelming majority of doctors you consulted agreed that there was a 90 percent or greater chance that you had a disease which would cause increasingly debilitating and painful symptoms leading to a hideous and agonizing death unless you immediately began treatment which would both prevent the worst symptoms of the disease and save your life, what would you do?
Thanks for the interesting links. Again the question remains: To what extent does MAN-MADE CO2 play a role in the greenhouse effect? This is what the whole discussion is about I think, or at least should be.
Indeed we know that water vapour plays the dominant greenhouse role, and that CO2 plays a significantly lesser role, of which the man-made part is only a small fraction. Once you begin to multiply fractions you quickly approach negligible magnitudes. Surely man-made CO2 contributes to the greenhouse effect, but I would say over a neglible range. And next, you have to factor in the contributions from extraterrestial activities such as solar and cosmic particles. So when you multiply a quarter times a twentieth times a tenth and so on…you quickly see where one ends up.
I think this is what the debate has to focus on…determining the magnitudes of these fractions, and to do so without constantly fudging the numbers. Are we really impacting the climate? Or are we only talking about whether or not we should invest huge sums of money, and change how we live our lives, so that we can go from having a negligible impact to having a slightly less than neglible impact?
Comment by Pierre Gosselin — 24 Mar 2007 @ 4:36 AM
Well, I’ve written quite a few posts here and I have to admit that my mind was already made up before I started, so I think I’ll move on.
But to sum up my general view on all this…
I am very suspicious of any theory that has to introduce more and more factors to keep being able to explain experimental results. e.g. The global cooling after WWII – CO2 cant explain it so you introduce other pollutants to explain it – in which case you could advocate increasing pollution to offset the CO2 (obviously I wouldn’t)
The introduction of a ‘feedback loop’ to explain the t-leading co2 problem is nuts. If rising co2 levels warm the oceans, the oceans emit more co2 which warms the oceans which emit more co2. The only feedback I can see is that – once warming starts nothing could ever stop it. The fact that we are alive today is evidence that the theory is pretty weak.
I don’t believe that the research is objective – huge amounts of money are available to research it.
I don’t believe that consensus science is science at all.
A computer model may model past climate events – but this is absolutely no indication of any future accuracy. These models are presented to the public as some kind of divine oracle that can tell us what will happen and are now partly influencing global political decisions. As someone who has spent 25 years writing computer modelling software I find this a very scary idea.
I am very suspicious of the political driving forces behind the public face Global Warming theory – not the scientists themselves I hasten to add.
Taking into account all the discussions, graphs and references to peer reviewed work – I simply don’t believe that anyone knows anything like enough about how the climate really works to make any realistic prediction.
If it turns out that this theory is wrong, science will have a very hard time recovering any form of credibility and that may be the saddest result from this episode.
Just as an aside, I am totally in favour of a move away from carbon based fuels probably to hydrogen. I also have a completely irrational faith in nature and its ability to look after itself.
After a few days posting here I’ll give it and you all a break.
I would like to thank everyone who replied to my posts. Even though I am completely unconvinced by many of your arguments I do appreciate the time you took to present them to me.
All the best
ps. Having a background in physics, I am assuming the comparison of uncertainties in Global Warming to General Relativity was a joke
Pierre Gosselin, When you have a system with sources and sinks, you wind up with what is essentially the same differential equation we’ve all solved–filling a bucket with a hole in it. As long as the sources put in a volume less than a critical amount, the bucket will not overflow. However, go above that amount, even by the tiniest flow, and the bucket will overflow. Based on the fact that CO2 has increased by over 40%, we can conclude that we are above the amount the sinks can absorb. Based on the changes in carbon isotopic abundances, we can conclude that the carbon source is fossil and so it is anthropogenic carbon emissions that have pushed us above the critical level. We know that CO2 contributes somewhere from 8-12% of the greenhouse effect on Earth–and rising. These are all things we KNOW.
What we do not know are the effects of these changes–something that is inherently difficult to predict because climate is a chaotic system, and you cannot predict with certainty how a chaotic system will react to a perturbation. The potential effects of climate change are critical to understand if we are to come up with effective mitigations for them. In this effort, modeling is important, as are studies of paleoclimate in past warming epochs. Anything we learn is likely to decrease the cost of both climate change and its mitigation.
At this point, I am afraid we cannot avoid climate change. We can make it better or worse, though. Developing mitigation strategies will take time, and anything we can do to slow the worst effects and buy us more time will be a good investment.
So the argument about the causes of climate change is pretty much settled. The role of scientists now is to provide the best advice we can to policy makers on the likely consequences and how we can mitigate them. Of course climate researchers will continue to investigate mechanism–all of them, including cosmic rays (talk about a trivial contribution). The better we understand these, the better will be our models. But we are at a point where a revolution in our scientific understanding is very unlikely.
[[they give it a 90% probability - on this site it becomes an absolute certainty. Anyone taking the 10% option is called a denier.
if, like the beautiful girl, the ipcc had said there's a 1 in a million chance we're wrong - then case closed. But 1 in 10 is something else altogether.]]
Okay, Phil, load a ten-shot revolver with nine bullets, give the chamber a spin, hold it to your head, and pull the trigger once. You’ve got a 10% chance of surviving, and after all, 1 in 10 is something else altogether.
[[ We know that CO2 contributes somewhere from 8-12% of the greenhouse effect on Earth--and rising. These are all things we KNOW.]]
Kiehl and Trenberth (1997) estimate 26% (clear sky), but it varies. But none of these percentages are as meaningful as they sound. It’s not really something you can divide into percentages, because the wavelengths one greenhouse gas absorbs at are often absorbed at by another as well — “band overlap.”
Hydrogen? Are you kidding?
Burning hydrogen emits water. All that extra man-made water vapour will wind up in the atmosphere, and then the CO2 villifiers will finally admit that water vapour is an important greenhouse gas after all!
Comment by Pierre Gosselin — 24 Mar 2007 @ 12:48 PM
“At this point, I am afraid we cannot avoid climate change.”
Well, don’t feel bad about that. So far no one has been able to do it in the last 4.5 billion years.
Comment by Pierre Gosselin — 24 Mar 2007 @ 12:53 PM
Re #237: Pierre Gosselin — Using the simple orbital forcing theory, without anthropogenic effects, the climate should be very gently cooling. But it is warming. So the answer is slightly more than 100% of the warming is due to humans.
Comment by David B. Benson — 24 Mar 2007 @ 2:30 PM
Re #238 “I am very suspicious of any theory that has to introduce more and more factors to keep being able to explain experimental results. e.g. The global cooling after WWII – CO2 cant explain it so you introduce other pollutants to explain it – in which case you could advocate increasing pollution to offset the CO2″
Why would you expect a system as complex as the Earth – including its biota and most especially its human population – necessarily to be explicable in terms of a small number of factors? I’d guess you’re importing the attitudes that have served fundamental physics very well into a context where they just don’t make much sense. And the climate scientists didn’t introduce other pollutants – industry did, and then had to cut back on them due to political pressure arising from their bad effects.
“If rising co2 levels warm the oceans, the oceans emit more co2 which warms the oceans which emit more co2.”
The warming effect is logarithmic in the atmospheric concentration of CO2 – can’t you see that makes a difference?
“I also have a completely irrational faith in nature and its ability to look after itself.”
You said it, Phil – completely irrational.
It’s too bad PhilC didn’t (apparently) bother reading the peer-reviewed literature on AGW, including the IPCC Reports, and the reports from the Royal Society, NAS, etc. I sense that a lot of RC visitors mistakenly interpret the comments made on RC threads by (mostly)non-climatologists as representing discussion and debate by climatologists.
In reference to the C02 feedback mechanism and others that have been mentioned, such as albedo and water vapor, it seems that these taken by themselves would create an unstable equilibrium. I come from a math background and don’t know much about the climate models–I’m thinking of an ODE like y’=y, where there is a bounded solution if y(0)=0, but for the tiniest deviation in the intial condition, the solution grows unbounded. I’m interested to learn what damping factors exist that would allow a more or less stable solution (oscillating perhaps) to the homogeneous problem (that is, without an external forcing function to muck things up). I did see the comment about C02 growing as a function of the log, but even if y’ = lny you still have an unbounded solution (related to the number of primes less than y as it turns out!). Is it the case that y’ = f(y) and f rapidly approaches zero, perhaps?
He admits his mind was made up before coming here (and didn’t even know what the IPCC SPM was), and he admits irrational beliefs concerning the earth “taking care of itself”. (Which is really besides the point; let’s agree the earth takes care of itself, so? since it’s not a sentient being it could care less whether humans suffer or civilization collapses). And what is one to do with someone who prefers the 1 to 9 odds over 9 to 1 odds? And especially if the consequences of being wrong are so dire. But I guess if one thinks that AGW is nuts, then clearly there won’t be any consequences so all those arguments fall on deaf ears. It’s like if you’ve convinced yourself that you are a great driver and will never get into an accident (despite the fact that most people over their life times will) so you don’t by insurance.
And I would like to say that I was impressed by the explanations given concerning the C02 lag issue by the non-experts and if he had wanted more detailed explanations the side bar is there, as well as the literature. The patience and professionalism you all display is amazing. I get no such courtesy on sites that feature anti-AGW threads, I can assure you. (And taking your collective lead, I fully admit I could have dropped the dumb and dumber thing, I’ll try to restrain myself in the future.)
One can only hope that folks with Phil’s mentality are a minority. Fortunately, at least among world governments, his type of thinking doesn’t seem to have much influence and seems to be having less and less as the days go by. I mean really, Inholfe and the rest have basically been reduced to gimmicky personal attacks on Gore and other advocates and, I could be wrong, but I think most rational people realize that alleged hypocrisy doesn’t change the physics of C02 absorption of infrared rays, the outcome of the recent debate notwithstanding.
> Yeah, my SUV don’t make no stinkin’ water vapor …
Chuckle. Someone from a warm climate, who never saw a muffler rusted by driving mostly lots of short trips, might be able to sustain that delusion, but it couldn’t survive passing high school chemistry.
Having a background in physics, I am assuming the comparison of uncertainties in Global Warming to General Relativity was a joke
Straw man. The comparison was between the theory of Relativity with the theory of the Greenhouse Effect, which was first discovered by Joseph Fourier in 1824, first demonstrated in laboratory experiments in 1859 by John Tyndall, was first developed into a quantitative theory by the Nobel laureate Svante Arrhenius in 1896, and has since been backed up by literally millions of strands of evidence. It is straightforward physics and is at least as solid as Relativity,.
The uncertainties are about quantification of the effects in a highly complex climate system, not about Greenhouse Effect theory.
[[Burning hydrogen emits water. All that extra man-made water vapour will wind up in the atmosphere, and then the CO2 villifiers will finally admit that water vapour is an important greenhouse gas after all! ]]
Water vapor is a stronger greenhouse gas than CO2, yes. But a molecule of water vapor only stays in the atmosphere, on average, for about nine days. A carbon dioxide molecule stays in the atmosphere, on average, for around 200 years. We could double water vapor tomorrow and nearly all the excess would be gone in a month. So this is not a valid objection to a hydrogen economy.
Remember that water cycle we learned about in science class — evaporation, condensation, precipitation. It’s an extremely fast cycle compared to the carbon dioxide cycle.
Re 255, Ones famous scientists critique of Science was that it marches funeral by funeral to the next discovery. Successful as relativity is (not refuted as yet) it only takes one new experiment to call it into question.
Science is like that. Climate Change unlike relativity is an amalgamation of various scientific inputs from various disciplines and its working relay on a lot of models executed on computers and hence that somehow seems to make it different more pure single discipline approaches. Empirical though it is, climate change is open to more interpretations maybe.
#245, “Yeah, my SUV don’t make no stinkin’ water vapor you CO2 villifyin’, do goodin’, “flyin’ in the face of economics” science guys/gals.”
Be not afraid to do good.
Did you see the movie, THE JERK? That’s more like our situation. No one knew CO2 (the by-product of our high living standards) would have harmful effects, except maybe Arrhenius and a few others. I didn’t know until the late 1980s. The media were gracious enough then to inform the public, then there was a deep ice age of their silent treatment, so younger persons couldn’t learn about it. One friend even said she had thought GW had been disproved, since she hadn’t seen anything about it on TV or in the news after the early 90s.
So we’ve all nearly been caught, like “the Jerk,” doing things that seemed good and fine, but had a down side.
Now we should look for solutions that can help us throw out the bath water of GHG harm, without throwing out the baby of a good material life. It would be helpful if everyone joined in looking for solutions, and at least implemented those that do not reduce one’s material life and happiness.
Comment by Lynn Vincentnathan — 25 Mar 2007 @ 8:59 AM
Barton makes another good point: the critics don’t have even a basic understanding of 8th grade earth science. With it they would have no argument.
If you have a degree in physics, you surely know that terrestrial objects (including earth and ocean surfaces) emit longwave infrared radiation in proportion to their Kelvin temperature raised to the 4th power, yes? Some of that will be trapped by atmospheric CO2, but much will escape, thus, as temperature rises, so will emission of terrestrial longwave IR, and the earth’s (and ocean) surface will reach an equilibrium temperature dependent on, among other factors, atmospheric CO2 level.
(If I am mistaken on this point, I trust someone will correct me?)
At the beginning of the 1980s I was the national training director for a carburetor company. It was part of my job to convince auto mechanics and dealership owners to not disable and destroy the anti-pollution equipment on new cars, which was being done. I would put a car on a dyno and disable the catalytic converter. That way I could show the mechanics on an exhaust-gas analyzer how much NOX, CO, and CO2 (these are the three I remember) was produced under varying loads and speeds. We would make horsepower measurements. Then I would re-able the anti-pollution equipment so I could show them that NOX and CO fell to virtual zero even under heavy loads, and that horsepower was not as negatively affected as they had been told.
And then we would point out that CO2, which we described as a harmless gas that plants used, was the only meter on the gas analyzer that still had a significant reading.
I’m certain water vapor is a significant combustion product of gasoline, but I don’t think our exhaust-gas analyzer measured it. I guess we relied on the rain gauge.
I don’t believe that consensus science is science at all.
One often sees such statements from AGW non-believers, and I must say that I find such sentiments odd.
So, PhilC, seeing that you “don’t believe that consensus science is science at all”, what if (hypothetically) the consensus science view was that AGW was nonsense? Is the natural corollary of your position that you’d believe in the non-consensus view, i.e. that you’d then believe in someone who was positing a (non-consensus) link between anthropogenic CO2 emissions and global warming? Surely not! So, with due regard to your stated belief, would you believe in the consensus science view after all in that instance? It would seem you could not, not without sacrificing your belief.
Of course, that is a hypothetical situation that can never arise (since AGW is a reality ;-), though curiously it once was a non-consensus view), and so perhaps it is an unfair question to put (though I think not).
So, what about a less hypothetical example or two. Consider, if you will, the consensus science contributions of the likes of Arrhenius, Avogadro, Bernoulli, Bohr, Boltzmann, Bragg, Brewster, Carnot, Cavendish, Chadwick, Crick, Dalton, Dirac, Einstein, Faraday, Galileo, Gauss, Heisenberg, Hooke, Joule, Kepler, Kelvin, Langmuir, Maxwell, Newton, Ohm, Pauli, Pauling, Planck, Rutherford, Schrodinger, Snell, Thomson, Van’t Hoff, Watson, Zeeman, … (the list is virtually endless)? Are their consensus science contributions not science at all either?
Sounds to me then, if you are correct, that we need some new textbooks, what with all that consensus nonsense out there.
Nothing is “all” attributable to any one thing, Tom.
Who gave you that idea? Seriously, people are misrepresenting the science and when people come in with these mistakes, I want to know if it’s bad journalism, or excellent PR work, that’s getting these ideas into people’s heads so effectively.
Oh, and, Tom, which climate did you mean? The increase in variability isn’t even everywhere, and if you look this up (for example at NOAA’s page, you can find it) you’ll see why that statement is wrong. Who told ya?
Re #266: tom — I am an amatuer at climatology. My assessment is that all the warming is entirely attributable to man. The reason is that from orbital forcing theory, the climate should be, on average, very gently cooling. But it is not.
At the same time, we know that carbon dioxide is a greenhouse gas. We know that the concentration of carbon dioxide in the air has considerably increased and we know that this is due to bruning fossil fuels. Hence my assessment.
Comment by David B. Benson — 26 Mar 2007 @ 2:32 PM
Ok your interpretaion is that the IPCC is 90% sure that most of the current warming is due to man’s inluence, correct.
Ref:263 & 264
“what if (hypothetically) the consensus science view was that AGW was nonsense? Is the natural corollary of your position that you’d believe in the non-consensus view, i.e. that you’d then believe in someone who was positing a (non-consensus) link between anthropogenic CO2 emissions and global warming? Surely not! So, with due regard to your stated belief, would you believe in the consensus science view after all in that instance? It would seem you could not, not without sacrificing your beliefâ��
Youâ��re assuming I am just being contrary.
Maybe what I should say is that while the consensus is a valid and important part of the scientific process – it proves nothing in itself.
Science is about discovering an accurate way to explain the physical universe. The accuracy of science is measured by how close the predictions are to the real world â�� the greater the difference the more unclear, or plain wrong the science is.
And the more unclear the science the greater the need for a consensus â�� Newton does not need a consensus.
I expect we agree that climate is an immensely complex system. At the moment there is a â��consensusâ�� theory of how it works and is sufficiently understood to make predictions. Yet, all it would take is for one (as yet) unknown driving factor to be discovered and that current consensus would be proved to have been completely wrong/useless and very damaging.
but as â��â�¦.AGW is a reality ,â�¦â�� you feel sure the chance of any further significant factor being discovered is absolutely zero?
Let me eat some humble pie. Iâ��ve learnt a good deal on this site, some of it has begun to make me think differently about global warming. I also accept that some of my counterarguments do not stand up.
But even accepting that the physical processes of elements within the GW theory are well understood, I still think it is a huge leap to extrapolate these up and arrive at a â��Theory of Climateâ�� â�� one so well understood that a computer model can predict the future.
Computers make a pretty laughable job of predicting the weather beyond a few days – about 18 months ago we were given a long range forecast for a bitterly cold winter which then failed to materialise. So this just confirms my belief that all computer model predictions should be treated with great scepticism â�� sorry, but after 25 years in software modelling thatâ��s my opinion. On which we can disagree.
Re #276: I wish people would stop talking about consensus. It is really just a lazy appeal to authority rather than making the effort to explain the issues, and also a convenient strawman for denialists. The fact is most climate scientists conclude that human activity has played a large part of the recent global warming. If you have the time, then question that view and find out why it is held.
Climate is chaotic, there are large uncertainties, and there is no single “theory of cliamte”. Climate models are useful investigative tools, and should not be misunderstood as accurate detailed forecasts. Still, it is clear that the climate of the 20th century cannot be explained without anthropogenic contributions, and it is clear that further greenhouse gas emissions will tend to make temperatures rise even further. The may well be other factors that influence the climate, but carbon dioxide accumulates with time, and its contribution to climate will increase, and eventually overwhelm other factors.
A climate model is not a weather model run for a longer time. Climate is an average, and the low frequency variations in climate are much easier to predict than the high frequency variations in weather. For example, the weather forecast may be off by 5 or 10 degrees in a few days, but I can predict the average temperature 6 months from now within a degree or two simply by looking at a climate chart.
Keep asking questions. It is the only way to learn. I still have a lot of questions, which don’t always get answered to my satisfaction right away. My skeptical attitude does not accept statements based on faith or authority, I need to understand why. But with patience, learning does occur.
[[Computers make a pretty laughable job of predicting the weather beyond a few days ]]
Weather is day-to-day variation, and is chaotic (an “initial value problem”). Climate is a long-period (30 years or more) regional or global average (a “boundary values problem”). I don’t know what the temperature will be tomorrow in Kinshasa (weather), but I can be pretty sure it will be hotter than in Stockholm (climate).
It is not correct to compare the weather forecast with a computer simulation of the climate. While the weather is about predicting a particular path in time (of temperature, wind speed, …), in climate one is interested in averages, which are much easier to predict. While it may be difficult to predict the temperature of a particular winter, there is “no” difficulty in forecasting the distribution of temperature for the winters around 2100 (given CO2-concentration at that time); for example that there is a x% probability that the tenperature will be between T1 and T2. Take a look at http://www.bbc.co.uk/sn/climateexperiment/theresult/abouttheresults.shtml to see how this works.
GCMs reproduce climate over the 20th century very well, which gives me a lot of confidence. Even if we grant that GCM are imperfect, should we just ignore their results and trust the uninformed opinion of some contrarian? Better safe than sorry.
Re 278 (Blair Dowden).
Like you: “my skeptical attitude does not accept statements based on faith or authority, I need to understand why”. I also need to understand the evidence and the arguments. I do not, however, agree with another statement of your’s: “it is clear that the climate of the 20th century cannot be explained without anthropogenic contributions, and it is clear that further greenhouse gas emissions will tend to make temperatures rise even further.” However hard I look, what I can see is evidence that these statements could be true, but not that it is ‘clear’ (ie. certain) that they are. In my view, the agreement of many with your statement is based on belief and opinion, rather than a science-based conviction. Many others agree (particularly non scientists) because they accept them as part of a ‘scientific consensus’. However much such statements are repeated as ‘clear’ or ‘certain’, I am not going to believe just because its ‘drummed into me’. The case must be convincing. In my view, it is not (and I am a liberal, environmentally conscientious scientist).
re: 281. Yes absolutely, nothing should be “drummed into” anyone. You can easily read the science for yourself. The IPCC report, for example. Which shows that the warming over the past 30 years simply can not be explained by sole consideration of natural forcings or cycles. Only by considering the additional forcing of man-made CO2 is the warming explained. No other process has been presented in the scientific journals by so-called deniers or skeptics which can explain the trend. Thus, they spread “disinformation” about the science. Or worse yet, about the climate scientists themselves. And yet sadly many of those without any credentials in the field of climate science (Crichton, Monckton, etc.) are given soap boxes via the internet or certain media to exclaim that they know something that none of the climate scientists do. That is not science. The science is unequivocably convincing once you read the information available. The consensus is strong throughout the climate science field, as you can also determine. And the scientific debate is quite over, despite the constant cries of those who simply do not understand the science. Or who simply can not admit they are wrong.
Re #281: PHE — What part of the physics of greenhouse gases iss not both clear and certain? What part about the measured increases in greenhouses gases in the last 50 years is not clear and certain? What part of the known uses of fossil fuels in the last 50 years is not clear and certain? What part about the C14 ratios in the air in the last 50 years is not clear and certain?
Comment by David B. Benson — 27 Mar 2007 @ 1:21 PM
Re 282 (DB Benson).
On a general point: The current temperature is not shown to be unprecendented within the past 2000 years. The current temperature trend is not unprecedented in the past 2000 years. On this basis, nothing exceptional or unprecendented is currently occuring. In fact, the current trend (since 1998) is not even upwards.
To answer your questions: (i) CO2 is a minor greenhouse gas. The theory that rising CO2 concentrations could cause a temperature rise is plausible, but so far not demonstrated to be the case. So far, the correlation is no more than circumstantial. (ii)Measurements show an increase in CO2, as well as some other minor greenhouse gases. This is not disputed. What is certain is that there is no correlation between temperature and CO2 rise from 1945 to 1978 and from 1998 to 2006. (iii) We have increased fossil fuel use enormously during the past 50 years – correlating with a substantial improvement in quality of life and life expectancy for most (by no means for all). While coal mining in the past was a very dirty business, this has improved enormously in recent years with cleaner emissions and better safety records. (iv) tell me about C14 ratios. If this supports your point of view, I’m interested to hear. Some readers here will say that many of my comments have already been addressed and rebuffed. But I don’t agree.
I have no ulterior motive other than to defend the integrity of good science. I am all for protecting the environment (eg. discouraging SUVs, recycling, reducing waste and pollution, etc). One hypocrisy I could never support is ‘carbon offsets’ which is simply an excuse for people like Al Gore and Tony Blair to continue polluting as they are, while preaching to the rest of us.
and hoping this information is accurate I see a list containing these views
..the model mean exhibits good agreement with observations.
..The individual models often exhibit worse agreement with observations.
..Many of the non-flux adjusted models suffered from unrealistic climate drift
..All models have shortcomings in their simulations of the present day climate of the stratosphere, which might limit the accuracy of predictions of future climate change.
I have a couple of questions, and I’m am interested to hear any views on this
if the climate models are less prone to ‘noise’ than weather modeling then why is there such a variance between them – surely this would all be ironed out?
Second question, is that fact that the ‘mean exhibits good agreement with observations’ such a surprise
A good model should be in very good agreement with the real climate so all the modellers start off aiming for the same point, there’s no point desinging a model that will give ‘unrealistic results’
Any models that do give these unacceptable answers would be rejected as wrong leaving only those that are close to the observations with a natural statistical spread around this point.
So if you take all the models that look realistic wont they naturally result in a mean with good agreement with observations but with individual models exhibiting worse agreement with observations.
Re #276 (philC): “Newton does not need a consensus”
Yes he does. First off, it is acknowledged that Newton is not infallible: his copuscular theory of light is mostly ignored these days, and Einstein’s general relativity explains phenomena that Netwon’s universal gravitation gets wrong (e.g., Mercury’s orbit). But the main thing is: there’s no big political lobbying effort trying to discredit the use of Newton’s theories, which means that the general public isn’t being bombarded with half-baked “alternative” theories and hence no reason for the scientific consensus view to be explicitly pointed out — the consensus is reasonably approximated by what “everyone knows”.
Earth’s Climate: Past and Future
W.H. Freeman, 2001.
Comment by David B. Benson — 27 Mar 2007 @ 7:21 PM
289, 290. In turn, I suggest the IPCC TAR Scientific Basis (we are still awaiting this for AR4 of course). This is a pretty good review of climate science and of what we know. Just be wary of the ‘Summary for Policymakers’, more accurately described as the ‘Summary by Policymakers’. A key challenge is to find, in the main reports, the scientific backup to the key conclusions stated in the Summary. This then demonstrates how much of the key conclusions are opinion rather than scientifically rigorous conclusions.
Re #281: The value of a discussion like this is it can reveal sloppy thinking, or at least writing. So I want to amend my statement “it is clear that the climate of the 20th century cannot be explained without anthropogenic contributions“. By “clear” I mean the best available explanation, not certain truth, and it only applies (for me) for the last few decades. While there is is every reason to believe anthropogenic greenhouse gases played a role in the earlier part of the century, it was a much smaller role and they were counterbalanced by other forces (eg. aerosols). Climate modelers claim that the greenhouse signal is required to reproduce that climate, but that argument is beyond my understanding, so I should not be making it.
The last 30 years is different. There is a clear warming trend (that word again, but this time I stand by it), and a convincing explanation for it. We are able to accurately measure all climate inputs for this period, and none of the others can account for the warming.
I am willing to talk more about greenhouse forcings later if you want. No time now.
[[The theory that rising CO2 concentrations could cause a temperature rise is plausible, but so far not demonstrated to be the case. So far, the correlation is no more than circumstantial. ]]
It doesn’t depend on a correlation. It’s basic radiation physics, proved in the lab as early as 1859. CO2 is largely transparent to sunlight but a good absorber of infrared light. Put more of it in the air, and the ground will become warmer if all else is equal.
[[(ii)Measurements show an increase in CO2, as well as some other minor greenhouse gases. This is not disputed. What is certain is that there is no correlation between temperature and CO2 rise from 1945 to 1978 and from 1998 to 2006]]
You can’t pick out the parts that seem to make your case and ignore the rest. You have to use all the available points, and you have to account for all the relevant factors. No one is saying CO2 is related one-to-one with temperature. Things like changes in sunlight distribution, aerosols, albedo and other greenhouse gases also affect temperature. But CO2 is responsible for most of the warming of the past 30 years, which we know from correlating all the data for the past 150 years.
I understand you climate guys getting frustrated about comparisons between weather forecasts and climate models, but I think the comparison is apt.
The climate , like the weather , is subject to interactions which are difficult to identify . TO say the least.the laymen < me> can’t even conceive of a model which could capture the variables that affect climate. Doesn’t mean it can’t happen.
And by the way. The vast majority of weather forecats ARE accurate. The ones that ARENE’t get played up out of proportion.
As our local anchor guy once said: “.. Well Dave, I saw alot of people out there this morning shoveling their partly cloudies out of their driveway”
That is one of the reasons I lose sleep over climate change–the only thing that restricts what state the climate goes into is energy–add energy, and it is a certainty that climate becomes less predictable because there are simply more states it can occupy.
According to http://classes.yale.edu/fractals/Chaos/ChaosDef/ChaosDef.html, “chaos”
in the mathematical sense is often referred to as “deterministic
chaos” to distinguish this use from the everyday sense of the word (“a
state of things where chance is supreme”, or “a state of utter
confusion”). The first use in mathematics is given as:
Li, T.-Y., and Yorke, J., “Period three implies chaos,” American
Mathematical Monthly 82 (1975), 985-992.
They prove that if a function f:[0,1] -> [0,1] has a 3-cycle, then f
is chaotic in this sense:
it has periodic points of all periods,
and there is an infinite collection of non-periodic points with
iterates that approach one another arbitrarily closely, only to
move far away again, and that never approach and remain near any
A standard definition now is:
Davaney, R., Introduction to Chaotic Dynamical Systems 2nd Ed,
A function f:R -> R exhibits deterministic chaos if it
satisfies three properties:
1) sensitivity to initial conditions arbitrarily close to every
point x, there is a point y with f^n(x) and f^n(y) iterating far apart.
2) dense periodic points arbitrarily close to every point x, there is a
point y with f^m(y) = y for some m.
3) mixing for every pair of intervals I and J, for some k f^k(J)
and I overlap.
So if we’re using “chaos” in the technical sense, it’s not only
compatible with determinism; it requires it. However, it’s not clear
to me how this sense can be applied to a thermodynamically open system like
Earth’s climate (or the entire Earth system of which it is one
G. Nicolis and Ilya Prigogine (1977) “Self-Organization in
Non-Equilibrium Systems”, would call the Earth system,
the climate, and coherent weather phenomena such as hurricanes “dissipative
structures”: thermodynamically open systems “feeding off” low entropy
energy sources to maintain their structure, often exhibiting spontaneous
symmetry breaking and in some cases progressive self-organisation over
time. Such systems do also show sensitive dependency to initial
(and/or boundary) conditions, but I think do not necessarily do so. In
particular, their long-term trajectory may be sensitive to some of
the possible small changes in initial or boundary conditions, but not
all. They often have multiple “metastable macrostates”: regions of the
system’s entire statespace which tend to maintain themselves once
established, but not indefinitely; a small external input when the
system is in the interior of such a region will leave it in the same
metastable macrostate, but if it is near the boundary, may shift it
into another – and which one it ends up in may (but need not) depend on precise
details of the external input. As any important system parameter has
its value pushed in one direction by external input, the likely result
is a period of instability, ending when a new metastable macrostate is
entered. If external inputs are pushing a key
parameter in a certain direction, there can be good reasons to believe that
the next metastable macrostate will have certain properties – e.g., if
GHG levels are continually increased, we can expect the period of
instability to be followed by a metastable macrostate with higher mean
temperatures, less latitudinal temperature gradient, less Arctic ice
etc. – but just what that macrostate is like might depend on exact
schedules and mixes of GHG emissions, and many other factors besides.
In summary I’d say neither weather nor climate is strictly chaotic,
both can exhibit sensitive dependence on intial/boundary conditions,
but do so in different ways and (as far as I understand what is currently understood in climate science), at the largest scale the results of dumping lots of GHGs in the atmosphere will be a hotter surface climate.
Re: Water vapor is a stronger greenhouse gas than CO2, yes. But a molecule of water vapor only stays in the atmosphere, on average, for about nine days. A carbon dioxide molecule stays in the atmosphere, on average, for around 200 years.”
Have we got some taggants to attach in order to prove this theory? How long can an angel dance on the head of a pin before he falls off?
Re: “We could double water vapor tomorrow and nearly all the excess would be gone in a month. So this is not a valid objection to a hydrogen economy.”
All we need to do is shut down the world’s economy every other month till things go back into “balance” as a famed climate researcher (Gore) would put it. Everyone just stays in bed for the month fasting – sounds a lot cheaper than windmills.
Comment by Bruce G Frykman — 30 Mar 2007 @ 5:43 PM
Re 299: Nick, would you go with stochastic to describe climate? True chaotic behavior would be very difficult to diagnose in a system as complicated as climate, but I would not rule it out at least in some portions of the phase space.
Re #301. Yes, I’d go with “stochastic”. Another term that might be useful, as it’s often applied to complex systems such as ecologies and economies is “path-dependent” – which also implies that where you end up can be very different depending on small initial differences, but doesn’t carry all the technical freight of “chaotic”, at least as far as I know.
If you want to nip this trope of the denialists in the bud, you should yourselves STOP using “causes unknown” if you are fairly sure that Milankovic was correct. Besides, it’s actually a point of agreement – both we and they think that it’s a sun-powered warming to begin with. And no one I know of is disputing that.
Nick and Ray,
You have to be careful when using concepts like deterministic and chaotic especially in relation to global climate, which is the sum of many, many interacting ‘systems’. Take, for example, the widely studied issue of the onset of turbulence in fluid dynamics.
A river flowing slowly has little turbulence, but areas of rapids have high turbulence. Still, you can predict that the net mass transport will be downhill. This issue also crops up in climate models, for example, an equilibrium climate sensitivity estimate produced by a model (for a doubling of CO2) doesn’t depend on the timescale; if you double CO2 in one decade, you get the same T(eq) as if you double CO2 over 150 years, if I understand it correctly. However, the transient climate response in the two cases is clearly going to be different.
If you take the example of forcing water through a pipe, the same amount of water might flow through, but in one case (slow laminar flow) the behavior is quite different from the other (fast, turbulent flow). Also, experimental chaos is only studied in very simple systems like pipes; trying to extrapolate this to the global climate system is quite a stretch, though an increase in extreme weather events might be comparable to the onset of turbulence; extreme weather events are closely linked to the transient climate response, not so much to the equilibrium climate sensitivity. Still, any broad statements about ‘the behavior of the climate system in phase space’ are probably nonsensical.
However, for the denialist camp, what they like to say in their talking points is that “climate is chaotic, so it can’t be predicted, especially at the regional scale, and this means all the models are wrong, and thus we shouldn’t take any action to limit fossil fuel use”. This is the argument that Roger Pielke Sr used over at Climate Science (A New Quote on Regional Predictability, Feb 20 2007).
This is the standard contrarian approach, as far as I can tell – take a very complex scientific discussion, strip it down to simplistic nonsense that fits your agenda, and then repeat, repeat, repeat. It’s true that regional climate predictability is very iffy (which is why people whose idea of responding to climate change is buying property in Alaska and Iceland are behaving foolishly), certain factors can be constrained – for example, regional climate change in the American West will likely lead to more frequent drought (see the Persisent Drought in North America discussion by Richard Seager). Whether or not the drought in the African Sahel is related to anthropogenic climate change? Such issues are complex because they involve both local and global issues – similarly, drought in the Amazon can be linked to local deforestation as well as to global climate change.
The bottom line is that broad statements like ‘the climate system is deterministic’ or ‘the climate system is chaotic’ just don’t make much sense.
Well (I’m just another reader, not a Contributor), seems to me they don’t need to go beyond the published science; the feedback once the process starts is known physics (temperature < -> CO2), and I gather is understood _better_ than whatever causes the nudges at various points when climate has changed in the past. I recall the fits to astronomical cycles are approximate, and the forcing involved is relatively small.
Take a rock rolling down a hill — something caused the rock to start rolling, various things change its velocity over time, and those may be poorly understood —- even though gravity per se is well understood.
Maybe the same story would be ‘continued on next rock’ — but maybe not, something else may kick that one off.
I think the science is focusing on forcings and feedbacks because, whatever happened when previous big changes ran their course, this one’s so much faster that the past is only useful, not determinative.
Have you read Ray Pierrehumbert’s paper on ‘Science Fiction Atmospheres’? (It’s linked at his website, his name’s listed under Contributors). It gave me a glimpse of how to think about what might be possible, and what we don’t know.
There seems to be a lot of discussion about climate models and whether they are deterministic or chaotic.
Reading this thread it sounds as if on one hand the laboratory physics is very simple and fully understood while on the other no single climate model follows the climate with any great accuracy implying that once the physics gets out of the lab and into the atmosphere it is not really well understood.
Although computers do a wonderful job of simulating airplane wings this is surely different. In that case the model is being used to explore different wing types using the extremely well understood mechanisms that wings undergo. The fact that these models produce better wings shows that they are accurately modelling the real item.
In climate science it seems the computer models are actually being used as a/the primary tool to better understand the climate mechanisms themselves because these are still not well understood.
Regardless of how impressive they are a software developments and how much people talk them up, the only real check on their validity is their ability to actually model our climate and so far no single model has managed this.
Until a single model (as opposed to a mean of models) actually starts being accurate can we assume that climate science is really not as well understood as the consensus would like us to believe.
I have read than most of Antarctica is cooling something not predicted by Global Warming or the models â�� is this correct.
Re 306. Bob, First, where did you get the idea that the models are inaccurate. They have gotten the trends right for over 20 years–and trends are what climate is about. They have accurately predicted the effects of volcanic eruptions.
Second, modeling is a very reasonable way of exploring a system that cannot be realized or simulated in the laboratory. If there are uncertainties, you conduct simulations over the range of uncertainties and report the robust results and perhaps the range of results.
Third, the models are all giving pretty much the same trends. Yes, climate is complicated. Yes there are things we don’t understand. However, the field is sufficiently mature that it is unlikely we will see any major revolutions in our understanding that change the conclusions.
If there are climate scientists out there who really disagree with the hypothesis of anthropogenic causation, they sure aren’t publishing. Even Lindzen acknowledges it is happening. He just thinks we’ll be saved by some miraculous restorative mechanism that keeps the effects from getting outside our comfort range.