Several people have written saying that it would be useful to have an expert opinion on the state of the surface temperature data from someone other than RealClimate members.
Here you go:
You don’t get more expert than Jim Hansen.
186 Responses to "Jim Hansen’s opinion"
Jim Bouldin says
Jim Hansen and 3 others were interviewed about Copenhagen last night by Charlie Rose. Good discussion. Should be available at the show’s website now or soon.
Daniel J. Andrews says
IOW, science is just another religion, or so it seems you are saying. As Ray has already pointed out you are just repeating outdated post-modernism, which you wouldn’t do if you were passingly acquainted with science. Google Nature of Science. There are a few articles you might enjoy.
I encourage you to also read science books written by scientists who are communicating for the general public in whatever area your interest lies. With all the commenters here we should be able to recommend books no matter the field you’re interested in.
Wrong. When I first started reading here I probably didn’t understand half the posts. I recognized the words (usually) but sentences didn’t make sense. Same with the comments. It was bewildering. Using your skyscraper analogy, I was having difficulty learning to operate the front door.
But I kept reading anyway, looking things up, finding explanations elsewhere, and locating other climate sites based on the links in RC posts and from the comments.
Now I understand most posts, and while I couldn’t build a whole skyscraper myself I can probably do some of the dry-walling. :-)
(don’t trust me with the electrical work though).
[Response: Thank you! I am glad to hear our efforts are worth it. It’s good to be reminded of that sometimes.–eric]
#85 dhogaza says: “You’re really going to question global temperatures based on records from one city in the United States?
Prepare yourself for some rude responses, if you are. Maybe you should rethink this a bit …”
No, that was not the intent of my post. I am just doing this project to get a “feel” for temperature beyond my memory of it and how the information looks. I collected an incomplete data set last year on record highs and lows (about 260 days worth) the 1930 had by an far the majority of record highs. While putting in the daily High and Low and comparing it to the Normal average, I was getting really noisy data. I am sure I could see the difference between summer and winter in the noise but I am not so sure of a small variation of 1 degree or so. The Global temp varies by about 200 F everyday. The noise level is extremely loud in the data set, how do you hear the sound of warming in loud noise was my question. From other posts, it is probably the fact I did not take a class in Statistics that harms my thinking.
But don’t discount Omaha as a hinge point on climate. Look at its location. Central of a continetal mass not moderated by oceans or large lakes. The temperature deviation from the mean is determined by large air masses from the South or North. I can see the extent of the air masses and they are quite large. This link gives me global views of air mass temps.
#93 Craig Allen says: “Norman, for pities sake, go get a book on basic statistics, or find some good resources on the internet. You aren’t going to get this knowledge by asking about it on a blog.”
I do need to read some basic Statistical theory. Time is one problem.
#94 Ray Ladbury says: “Norman, First, you need to realize that when you are talking records, you are of necessity in the realm of piss-poor statistics (1 per state by definition). Welcome to the world of extreme-value statistics. There are other ways to look at this that improve the stats somewhat:”
Thanks you both for your patient understanding with my ignorance of the science of statistics and what is it able to do.
Here is an analogy of what I am having trouble with. I drive the Interstate Monday-Friday. The speed limit is 60 mph (I like driving at around that speed). In the far left lane the speed seems about 70-75 mph.
The far right (with merging traffic and all) might average 50-55 mph.
So you have all these speeds. If you took the average speed of each car to create a data set you would have the noisy data I am finding with temperature data. Variations of 20 mph. Now you could easily see bad weather conditions or an accident in the noisy data as the speed would drop considerably. But if you were using this data to see if the speed had increased 0.5 mph over the last year and would then go on to state this increase will lead to more drastic speed increases in the future which will have the negative effect of more accidents and deaths, this is what I am perplexed about.
Extremely noisy temperature data (ranges 200 F or so a day) and finding a 1 degree F increase in 100 years of collection and claiming the world is headed for a disaster. I do understand the theory to Carbon dioxide warming the earth. I just don’t understand statistic well enough to see the signal in the noise.
[Response: Norman, your analogy isn’t very good but I do get your point. But the answer is easy — if you want to know if the average speed has increased by 0.5 mph, it doesn’t matter if the variations are 20 mph, or even 200 mph. What matters is how much data you have (N) relative to the variance (sigma^2). How well you know the mean value is given by sigma/(sqrt(N)). If you have large N (for example, hundreds of weather stations, or many many cars, then the uncertainty can be small. Indeed, as N gets very large, then the uncertainty goes to zero. On top of that, we don’t need as large N as you might suppose because the signal is much bigger than you seem to think, relative to the noise. Daily variations are weather; we’re talking about climate. The year to year variations are in fact just a few degrees, not 20, or 200 as you seem to think. So following up on your analogy, we’re looking at signal of something like 5 mph out of a variation of 20, not 0.5. And of course everyone knows the difference between 55 mph and 60 mph does change the accident rate significantly. I hope this helps.–eric]
I appreciate the comments. Let me try to explain. Prof. Hansen groups temperatures like this:
1 2005 0.62C
2 1998 0.57C
7 2004 0.49C
…in order to explain the disagreement between NOAA and NASA as to how warm 2007 was relative to other years. However, in Prof. Hansen’s PDF and in the email we see that differences less than 0.1C are not significant. Hence (for example) 2005 and 1998 are actually indistinguishable when one accounts for their uncertainties (which changes the groupings). In fact this grouping/ranking is probably quite artificial. However, explaining this would yield a much more complicated answer, and so it wasn’t preferred in the email, hence there is an economy with the truth.
I guess that temperature uncertainties also make it difficult to adequately say how 1934 compares to recent years.
Given the question from the journalist: “If NOAA and NASA can’t even agree what the temperature was last year, how can we believe what they are saying about the future climate”, and given the email trail, I think a more direct answer would be “The error bars don’t give us the necessary resolution”.
This seems to be the crux of the problem in climatology. The error bars are significant. However, the correct answer is widely understood within climatology, and the resulting positioning and messaging to present that correct answer leads to squabbles, when different parts of the story need to be neglected to present what is believed to be the correct answer.
There seems to be an unhealthy desire within climatology to avoid dueling in public (resulting in peer review manipulation and email trails like this). Hence Real Climate and people who bother to respond to questions are to be applauded, I certainly appreciate it.
As a responder above notes, the story on the web is far from clear (for example, the NPR story on ocean temperatures was published more than a year after the instrument or calibration problem was uncovered, hence the NPR story doesn’t really have an excuse as to why this wasn’t included).
I don’t have an agenda. I am just curious as to what is going on in this important field.
Completely Fed Up says
Norman, if you want a “feel” of the situation, read the IPCC reports and go from there.
Kim Cobb wrote: “feel that as climate scientists we must put ourselves at the very center of the discussions surrounding the causes and consequences of anthropogenic global warming. In doing so, some may come dangerously close to policy advocacy …”
First of all, climate scientists have exactly the same right to engage in policy advocacy as any other citizen.
They certainly have just as much right to engage in policy advocacy as do the various ExxonMobil-funded propaganda mills, frauds, cranks, “right-wing” media personalities, cynically dishonest second-rate hack writers, and deluded Ditto-Heads who flood the public discourse with lies and distortions in order to advocate a policy of doing nothing that would reduce the business-as-usual consumption of fossil fuels.
Moreover, climate scientists are uniquely qualified to advocate specific policy goals that must necessarily be informed by climate science, e.g. what we should aim for as a maximum anthropogenic temperature increase to avoid catastrophe, what we should aim for as a peak GHG concentration in order to limit temperature increase to that amount, and how quickly we must reduce emissions in order to limit the peak concentration to that amount. It may even be said that climate scientists have an obligation to advocate such policy goals.
The only caution I would offer to climate scientists is that while they have as much right as anyone to advocate any policy about anything, when it comes to aspects of policy that are outside their field of expertise — e.g. the potential of different energy technologies to reduce emissions, or the merits of cap-and-trade vs. carbon taxes — they are also no more qualified than anyone else, simply by virtue of being climate scientists, to comment on them.
When James Hanson talks about the urgency of limiting CO2 concentrations to 350 or less, I am persuaded. When he talks about the urgency of investing in “4th generation nuclear” or rails against cap-and-trade, not so much.
Ray Ladbury retorted to Snorbert that if he thought the CRU e-mails were a smoking gun, he must be smoking something. Wrong drug, dude. It’s obvious from their posts they are TWEEKERS (speedfreaks.) Doesn’t all that paranoia just slap you in the face? I bet they have huge arrowhead or nuts and bolts collections.
You’re right. If ZT did try to corroborate the NPR article through a google search using “are oceans cooling?”, he/she would get a mostly positive result. So, I was wrong to attack him/her on that point.
Still, I found his/her whole line of seemingly innocent and naive questioning and then the sneak attack to be particularly offensive. Reading any one of dozens of basic primers on global warming would have answered most of his/her “questions”.
I guess I’ll just go back to lurking and listening and not contribute to the noise.
Tenney Naumer says
The temperature data sets begin mid 19th century because control of the data sets was wrestled free of the Knights Templar from that point in time onwards.
Ken W says
“But don’t discount Omaha as a hinge point on climate.”
The state of Nebraska makes up approximately 0.03% of the global (i.e. planet Earth) surface area. So how is it that Omaha should be considered a “hinge point” on global climate information?
Why not choose this station in Manitoba Canada (no ocean there either):
It shows a nice warming trend-line of 0.12C/decade and a 10 yr average shows both of the last 2 decades significantly warmer than the 30’s.
While playing with individual station temperatures can be fun, it’s a meaningless exercise when considering the subject of global warming.
There’s nothing wrong with ranking them using the numbers generated by GISTEMP and then saying “note, rankings within 0.01C (or whatever) of each other are statistically equivalent”, and there’s nothing wrong with the way the “smoking gun” suggests stating it for journalists. “Here’s the ranking, but 2-6 are statistically tied” or whatever the precise wording was.
I know I said I would just lurk and listen, sheesh!
Norman. Dude. The 1930’s were really hot – in the contiguous United States and in the central plains, particularly. No one disputes that. In fact, 1934 is typically cited as in a statistical tie with 1998 as the hottest year on record – in the contiguous USA. The same does not hold true globally.
Southest Australia recorded the highest temps ever in February 2009. They had huge fires that killed over 200 people. Does that mean that 2009 was the hottest year over across the globe? No! In fact, the winter of 2008-2009 was unusually cold in the US central plains and New England.
Don’t confuse local events with global trends.
Ken W says
“I guess that temperature uncertainties also make it difficult to adequately say how 1934 compares to recent years.”
In the US, yes, but globally 1934 isn’t even close. Notice the error-bars on this chart:
“There seems to be an unhealthy desire within climatology to avoid dueling in public (resulting in peer review manipulation and email trails like this).”
The same can be said about evolutionary biologists (or any other scientific field where there’s a significant ideological-driven bias against the science in the public). Public squabbles about minute details confuses some of the public into thinking the entire theory is bankrupt. The proper place for scientific debate is in the scientific literature, where the audience is sophisticated enough on the complexities of the subject matter. And there’s no peer review manipulation other than wanting to keep the quality of journals high (i.e. keep out junk science or poorly written papers).
pete best says
This is the best scientific website ever constructed. I did not understand one word in ten 3 years ago when I started here either but on finding out all of the terms elsewhere and looking up the authors here to I came to understand the science of AGW. Most of all though I came to understand science itself and how it works. Denial makes no sense from a scientific perspective because science is skeptical on the whole. Sure a few scientists might always think they are right (perhaps – I have no proof of this) but most are skeptical and hence the only thing demonstrating a hypothosis or theory to be incorrect is peer reviewed science itself.
Denialists/contrarians etc do not submit skeptical work for peer review. They just blog and write stuff in the media and get on TV. OK some scientists themselves are in denial (Cristy and Gavin on TV the other day for example actively disagree) but they cant demonstrate their denial in peer review. Hunches without evidence dont get past peer review I would imagine on the whole.
John P. Reisman (OSS Foundation) says
#3 Snorbert Zangox
You are essentially questioning integrity here. But you are not considering the contexts involved.
There is nothing wrong with discussion and gleaning out problems.
There is nothing wrong with saying idiots are idiots as justifiable (or do you have a problem with free speech).
There is nothing wrong with testing data sets with different methods (‘tricks’ of the trade so to speak).
There is nothing wrong with dismissing ridiculous assertions such as yours that are to immature to have relevance in reality.
On the other hand, there is something wrong with someone hiding behind the moniker ‘Snorbert Zangox’, which shows that you don’t have enough integrity to post your full legal name.
“Pot meet kettle.”
PS You state:
What do you think all these articles and posts are about? Are you incapable of understanding all of this? If so, stop posting, you need to go back to kindergarten and start over (preferably in a European school where critical thinking is taught pro forma, obviously you have mastered the paradigm of the rote method).
Snorbert Zangox says
I am certain that carbon dioxide contributes to the ongoing warming, which I maintain is natural. I maintain that IPCC has greatly overestimated the role of carbon dioxide in the increasing warmth and has therefore greatly overestimated the effects that reduction in carbon dioxide concentrations can effect. Does the relative cooling of the stratosphere that you mention indicate the amount of warming that carbon dioxide is causing?
It seems to me that the environmental effects that you mention, increased warmth (ergo lengthened growing seasons), higher carbon dioxide concentrations (ergo more tree food), and widespread pesticide use (ergo fewer insect infestations) all would enhance the growth of trees. So why, in spite of the favorable conditions did the growth of trees abate during the late 20th century.
The Idsos have compiled results from hundreds of peer reviewed studies and determined that there was a warm period centered about 750 years BP that was world wide in breadth. You apparently do not like their interpretation of the data. There is no reason for anyone to believe that your conclusion that you base on a momentary glance at their results chart is superior to their conclusion.
[Response: Sorry, but there is no good evidence for “world wide” warmth at 750 years BP. And this sentence “I am certain that carbon dioxide contributes to the ongoing warming, which I maintain is natural” makes absolutely no sense.–eric]
the larch says
(17) oh, this meme again? i call DOUBLE D-K EFFECT. lalalalalala.
#104 response by eric.
eric, I want to thank you for you explanation. That does make a lot of sense. The noise of all those stations is much smaller than the local noise I am seeing in the one station and the signal to noise is easy to see.
I can see this in the other data manipulations I am doing. The difference between the average low and high is only about 2 degrees F. The daily difference in the daily data between high and low temp is very noisy.
Thanks for taking the time to educate me.
Ray Ladbury says
ZT, I want you to notice something about all the years you’ve looked at. They are all in this decade except 1998–the biggest El Nino in recent memory. It realy does not matter whether 2005 is second warmest or 2002. However, by assigning a numerical value to the temperature anomaly, we achieve a unique ranking. That is unavoidable. It takes a twisted, and frankly rather thick, mentality to project any sort of conspiracy on this.
However, one year is weather. To get to climate, it takes 30 years. And guess what. Seventeen of the twenty warmest years since 1880 have been in the past 2 decades. Even with red noise, that is significant. Now you can either learn something here at RC, or you can stay in your conspiracy-theorist fantasy world. Your choice.
Ray Ladbury says
Snorbert, have you bothered to look at the chart the Idsos designed? I will give you the benefit of the doubt that you have not. Some of the “warm periods” occur from 800-1000 CE, some from 1000-1200 CE and some start after 1200 CE. It takes some rather, shall we say interesting, notions of time to look at all those disparate and distinct warm periods and call it single global warm period.
It does no good to keep repeating the same meme over and over again when it has been challenged and specific instances of failure have been cited. Either abandon the position or state why you still hold it. “Yes it is, la-la-la-la…” does not constitute scientific debate.
John P. Reisman (OSS Foundation) says
#117 Snorbert Zangox
Eric answered you inline but I wanted to expand on the problem of your first sentence (which did not stun me because I have read your other posts and was therefore prepared for the inanity that may be expected from you):
You acknowledge that CO2 contributes to warming but maintain it is natural. Are you now willing to admit that burning fossil fuels does not add CO2 to the atmosphere?
Are you now able to show everyone here in the thread that you have identified the source of increased CO2 in the atmosphere from the pre-industrial to current levels, and it is completely natural and has nothing to do with humans burning fossil fuels?
Please do enlighten all with your knowledge.
Other problems with your post:
You maintain that IPCC has overestimated the role of carbon dioxide. Okay, show us your math in how you determined this.
As to “why, in spite of the favorable conditions did the growth of trees abate during the late 20th century.”
Well, land use changes… or are you unaware that we cut down forests to make cities and farmland?
Norman – and thank you for willing to be educated. So many people come here asking naive questions while posing as being genuinely interested in learning, only to expose themselves as being outright denialists lying in wait to hurl long-debunked cut-and-paste nonsense when people answer those questions in good faith, that regulars here tend to be cynical and mistrustful. That includes me.
There *are* many people who attempt to extrapolate single-station results into proof that it’s not warming, or that necessary adjustments in the record to account for new technology or station moves, etc are “fraudulent”.
Glad you’re not one of them after all.
The alternative that would be acceptable to ZT seems to be to not rank them at all … which is flat-out silly.
Snorbert Zangox says
Of course, it makes sense. Carbon dioxide contributes a small amount to the warming that began about 500 years ago when the climate began recovering from the Little Ice Age. Carbon dioxide contributes little to that trend. Furthermore, carbon dioxide alone will contribute little to future warming. Even the GCMs must invoke the spirit of positive feedback from water vapor and clouds to reach the heights of future temperatures that they predict. It seems to me that belief in those positive feedbacks is closely akin to a religious belief.
If you dispute the conclusion that the Idsos have made after their investigation of the literature of proxy temperature measurements, why don’t you prepare a rebuttal and submit it to them at http://www.co2science.org/about/contact_info.php. They have always been willing to accept criticism and to engage in debate with responsible persons who disagree with them. I will enjoy reading the exchange.
[Response:Are you referring to the unsubstantiated, unreference assortment of half truths, misconeptions, out of date nice-sounding but fundamentally wrong concepts and outright lies here, or to an actual piece of research?–eric]
Nick Barnes says
Thanks for the appreciative remarks about Clear Climate Code. I’d like to emphasize a couple of things about it:
1. It’s not really “Nick Barnes and his team”. Yes, it was my idea, and I started it, so I’m taking most responsibility (i.e. doing some project management, moderating blog comments, etc), and some of the work is also done by colleagues at my company, but I’m not writing most of the code, so I don’t deserve most of the credit.
2. No, I am not a sceptic, but the project welcomes sceptics. Everyone is welcome to join in.
3. It’s not as far advanced as one might guess from dhogaza’s comment 34. We have nearly reached the all-Python milestone (aiming for next week), and we have formed the view that GISTEMP does implement the algorithm described in the relevant papers. But much of the code is still too obscure to be definitive on this point.
Molnar(67). Interesting link, but it doesn’t cover the time period (1840-1910) of interest. During this period Crowley discovered warming at a rate comparable to recent periods. Crowley says that Mann also discovered the same warming trend during the same time period, but eliminated it from his graphs for reasons I don’t yet understand.
Crowley thought it should be included, so he did. Mann thought it should not be included, so he didn’t. Had Mann not removed this warming from his graph, the character of Mann’s resulting graph would have been considerably different.
Any thoughts on this ?
As to comments about the ranking, the problem is that the groups are separated by less than 0.1C, but the uncertainty in differences between the measurements is 0.1C. Hence the assignment of temperatures to specific bins (needed for the simple messaging) is misleading.
You can rank on any variable, but the ‘trick’ (in the usual climatology, i.e. non-pejorative sense) is to choose a bin size which yields a desired ranking of the groups.
Another question. If I look at the ocean temperature rise with time in Fig 3. of Prof. Hansen’s PDF. The temperature increase seems rather stable and linear, with time from about 1950 onward. Do the global temperature models reproduce this line, or do they show a more aggressive change in temperature with increasing CO2 concentration in the future?
I googled this, and found a nice article:
However, the fit to the land temperature data was so good (and therefore noisy), that I couldn’t pick out the long term trend. Presumably going out for a few more decades would show this – any recommendation on where to find such a model based projection? I am after a model which shows the effect on global temperature of an ongoing linear increase in CO2 concentration into the future.
Nick Barnes, regarding #3, I’d read this post by “drj”:
Yes, OK, “our opinion” and “we have formed the view” are weaker statements than my statement that you’ve “verified” that this is true.
steven mosher says
Dhog you wrote:
“Also, Mosher, note how “the team” has been responding to help. And don’t say “it’s because of Climategate” because the Clear Climate Code project predates that, and Barnes et al have been in touch with the GISTEMP code maintainer before.
#1. Bug fix and patch: murmurs of thanks and appreciation, code gets fixed.
#2. Screams that the use of FORTRAN proves the code can’t possibly work and therefore all of climate science is a fraud: phone is hung up.
#1: Clear Climate Code people.
#2: Typical follower of McIntyre and Watts.”
You need a fact check. First, I’m well aware that the work Nick has been doing predates climategate. He and I met a long while back on CA where he told be about his work. It makes you look silly to not be aware of this. Second,
The very day NASA announced that they would release GISSTEMP I went onto the thread at CA and asked everyone to show some class and post a thank you on RC.
I immediately proceeded to RC where I posted a thank you. That’s it. a thank you.
The post didnt make it through moderation. Further, since I had dinner last night with the one guy I know who has the GISSTEMP code running ( yes fortran) I can pretty much assure you that your imagined scenario with people calling up NASA and complaining about Fortran is wrong. The 4 programmers who sat there discussing GISSTEMP had nothing bad to say about Fortran. Most of us had worked with Fortran code, undocumented research code ( in my case code from NASA Dryden and AMES) We bitched more about the inclusion of Python. On other occassios we have complained about fortran, but then C programmers always do this. The thing that caused me the most concern when I first saw the code was not the fortran. It was the large number of IO steps ( probably required because of system limitation) It was a pretty fragile design. That doesn’t make it wrong, just danger will robinson.
The issue Gavin and I have is a philosophical one. It transcends the climate debate. It’s probably why I’ll agree to disagree with him for now. He believes that a written description is Necessary and GENERALLY sufficient to replicate results. I believe code is sufficient. I believe code is the best documentation of what science was actually performed because the words in a paper are not the science. They advertise the science. When the words are not sufficient to replicate the results, scientists find themselves in a position where personality ( witness scafette’s behavior) can insert itself. This should be avoided at all costs because personality can be just as corrosive as corporate interest, more so I think.
In 2007 Dr. Curry joined me in suggesting that more transparency would improve things. If you don’t like taking suggestions from me and other people who want open access to these things, then perhaps you will listen to her.
Finally, in the end I really don’t care if people want to rewrite history and pretend that they were always for the release of code. As I’ve said before. AGW is the best theory we have. I believe it. and the sooner people are more transparent with their code and data, the sooner some lingering doubts about minor matters will be removed and the sooner we can get on with the business of taking the appropriate actions. Why some people on the AGW side want to delay is beyond me, but the record is pretty clear that the strategy of stonewalling had a downside that was not unforeseen or unique in history.
steven mosher said: “I believe code is sufficient”
This is clearly false, as Nick Barnes’ work shows. Merely reproducing the exact result only shows that the code runs. Without a description of what it is supposed to do and how it is supposed to work, no amount of analysis can show that the code does what it is supposed to.
You do, indeed, have a philosophical problem.
Antiquated Tory says
I don’t know if this is the place to post this and I don’t know if Eric or Gavin will read this, but here’s an anecdote I’d really like to share with you.
I was talking today with a young woman who is a university student in a field unconnected with climate. Her boyfriend, who never met a conspiracy theory he didn’t like, was telling her that AGW is a hoax and sending her links to Monckton and the usual suspects. The young woman read all of this and Googled every one of their talking points. One of the places she ended up was here at RC. Her conclusion: the objections to AGW had either been refuted long ago or had no substance to refute in the first place, and her boyfriend, much not to her surprise, was talking bollocks.
David B. Benson says
ZT (126) — You are aware that CO2 concentrations have increased approximately exponentially? That gives a linear increases in ln(CO2) forcing, if that is what you meant.
Eli Rabett says
Steve Mosher is either silly, mendacious or naive (YMMV, but feel free to pick one) when he advises simply opening up the proprietary data in the CRU. Since others have provided examples of how some of the data is proprietary, no further answer is needed to Mosher and others who are claiming that none of the data the CRU uses is proprietary. They are WRONG. The major issue is open up proprietary data without permission and the next day you stop getting data updates. Tick your suppliers off enough and they put in a codicil that anyone who shares the data with you will get cut off. If you are in the business of building a long term record you can kiss your business goodbye. Since Mosher claims he is up to speed and serious. . .
John Davidson says
One of the things that is very noticeable is that some of the people from both sides of the climate debate are very selective about their selection of time spans. For example, some deniers like quote the last few years as “proof” that we are now facing a cooling phase.
AGW supporters could also be criticized for starting their graphs around 1880 – the end of an unusual dip in temperatures. This means that we don’t see see temperatures for the medieval warming that preceded this period. It would be more convincing to see recent warming in the context of what has happened to temperatures over since say 1000 BC.
[Response: Yes, of course. That’s why the deniers spend so much time trying to trash Mike Mann and Phil Jone’s reconstructions that go back 2000 years, since they are one of the best illustrations of this point. My emphasis in italics.–eric]
You need to get out more. The denialsphere’s been flooded with people making idiotic comments about choice of language, among other things.
Perhaps you’re not one of them. That doesn’t make the basic point I’ve made false.
Oh, geez, trying to reverse-engineer the physics from the code is about like saying you prefer to reverse-engineer C source code from the object bits rather than read what the programmer has written. The higher-level exposition in a scientific paper is much easier to follow, just as the higher-level abstraction of a modern computer language is much easier to follow than a few million 32-bit integers strung together.
Abstraction exists for a reason.
And if you believe it’s the fact that some code hasn’t been released in source form that’s holding back political action, you’re insane. Knowing that you’re not insane, I draw another conclusion.
#132. David B. Benson. Many thanks for your response. No I wasn’t aware that CO2 had increased exponentially – but that doesn’t sound unreasonable. The effect of exponential CO2 increase on temperature seems to be linear (I guess that this is what ln(CO2) forcing means). (I have to say, I am not at all sure what ‘forcing’ means. I have googled ‘CO2 forcing’ (etc.) and the ‘non-denier’ sites which show up (e.g. http://www.john-daly.com/forcing/forcing.htm) are quite baffling to me.)
I am curious to know what the models predict assuming a similar rate of increase in CO2 concentration, similar to the rate of increase that we see presently (even if this is exponential), say 30 years into the future. Is there a good link to such predictions?
[Response: http://www.IPCC.ch; RealClimate’s glossary]
Ray Ladbury says
ZT @127 These are the 20 hottest years on record:
Year La+Oc Land
2005 0.6058 0.9553 0.4884
1998 0.5768 0.8321 0.5087
2002 0.5575 0.8309 0.4784
2003 0.5566 0.7711 0.5102
2006 0.5524 0.8159 0.4669
2007 0.5499 0.9804 0.3874
2004 0.5332 0.7075 0.4809
2001 0.4939 0.7204 0.4416
2008 0.4869 0.7758 0.3721
1997 0.4618 0.5584 0.4498
1995 0.3991 0.6531 0.3191
1999 0.3953 0.6760 0.3237
1990 0.3701 0.5484 0.3279
2000 0.3632 0.5175 0.3406
1991 0.3239 0.4094 0.3105
1988 0.2886 0.4196 0.2585
1987 0.2867 0.2963 0.2999
1994 0.2820 0.3597 0.2699
1983 0.2715 0.3718 0.2508
1996 0.2586 0.2184 0.2986
Ray Ladbury says
Let’s try that again. Notice something about the years in question? Yup, they’re all within the past 30 years. And what is more, this decade is well over 0.1 degrees hotter than the last and well over 0.2 degrees than the one before. What is more, GISTEMP clearly displays error bars of +/-0.1 degrees on their charts. Are you really dim enough that you think there’s a massive conspiracy when they are clearly displaying their error bars and giving the same errors in private emails? Good Lord, you are thick.
[Response: My emphasis.]
Ray Ladbury says
Snorbert, since you refuse to address specific issues raised about your little science project, I can only conclude that you are trolling. I really urge people to go to the website you cite and compare those graphs in detail. It will show just what lying sacks of rhodent feces the architects of said propaganda are.
#141. Thanks Ray! Unfortunately we are not quite talking about the same thing. I am saying that Prof. Hansen’s suggestion for the dealing with the fact that NOAA and NASA disagreed about a given year’s temperature was economical with the scientific fact of uncertainty in the temperature measurements. Prof. Hansen was trying to provide a short sound bite which answered the journalist’s question, with respect to NOAA and NASA’s comments about temperature.
I was just looking at the facts of one email. I was doing that as I was curious to see whether the climategate emails are nothing to worry about – as asserted by many – or an indication that something could be improved.
I am not denying that the world is getting warmer!
There does seem to be a strong drive to ‘simplify’ the message almost to the extent of obfuscation – and I think that can’t be helping the messaging.
Thanks for the links on forcing and also model projections – they certainly help.
I am trying to digest Hansen et al, JGR, 2002, 107 – it will take me a little while! So far it looks like the projections in the future temperature in the paper have turned out to be high. This could well be a weather versus climate accident. (If there are more recent papers – please let me know).
I suspect that if the projections are correct – then nuclear power will be the only way that society can not implode. From what I have read here – that may be Prof. Hansen’s view too.
(Can I write in bold too?!)
John P. Reisman (OSS Foundation) says
#125 Snorbert Zangox
Are you saying that when water warms it does not evaporate faster?
[Response: my emphasis –eric]
Brian Dodge says
re the Idso’s MWP project;
they quote one paper as saying “significantly warmer” (+3.2°C) “than present.”
The paper’s online abstract says “…we modeled paleoclimate during the time of sympatry to be significantly warmer (+3.2°C annual minimum temperature) and slightly drier (−24 mm annual precipitation) than present,”
Another paper(the first one I got from their crap map page – 4 popup windows? WUWT?) states”Hence, we conclude that the peak mean warmth of the MWP was about a quarter of a degree cooler than that of the most recent decade or two of the CWP.” i.e. not global.
A few other selected quotes –
“(MWP: AD 800-1100)”
“driest 20-year period of their reconstruction was 1237-1256”
“occurring between 450 and 900 AD.”
“the relative abundance of Azpeitia nodulifera (a tropical diatom whose presence suggests the occurrence of higher sea surface temperatures), was found to be far greater during the Medieval Warm Period than at any other time over the 2000-year period studied, while during the Modern Warm Period its relative abundance was actually lower than the 2000-year mean.”[can you say [divergence problem”?]
“Hence, there was probably no significant difference between the mean annual temperature around AD 985 and the mean annual temperature of the 1980s and 90s.”
The only “level one study” for New Zealand they could find dates from 1979, so I checked google scholar(“new zealand” mwp) and found
Evidence for a ‘Medieval Warm Period’ in a 1,100 year tree-ring reconstruction of past austral summer temperatures in New Zealand
Edward R. Cook et al GEOPHYSICAL RESEARCH LETTERS, VOL. 29, NO. 14, 1667, 10.1029/2001GL014580, 2002
“Of equal interest in the reconstruction is the sharp and sustained cold period in the A.D. 993-1091 interval. This cold event is easily the most extreme to have occurred over the past 1,100 years.”
I conclude that at different times somewhere between about 450AD and 1250AD temperatures in various locations around the globe were warmer and cooler than current temperatures. The Idso’s see something different. YMMV.
Jaime Frontero says
Mr. Ladbury – and the rest of you on the side of the angels…
Look, invective can have value I suppose – not the least of which (in ideal circumstances) can be sparking the coveted “Oh! I’m an idiot” moment. At least where people like Snorbert Zangox (et al, 2009) are concerned.
But the thing is, it’s a waste of thought and effort to construct suitable and artistic invective for these people. They don’t care.
I mean… they’re *paid* to do this, right?
Neil Pelkey says
Phil’s advisor, Gavin’s boss, and Caspar’s and Mike’s coauthors are hardly “not associated with real climate” any more than Maggie L. Fox is “not associated” with Mark Udall. All of these people are fine people and quite knowledgeable, but claiming that they are unassociated opinions is a bit of an exaggeration.
[Response: If you don’t like ‘not associated’, then how about “having no influence over”. I’m talking about RealCLimate, not its individual members.–eric]
Jim Eager says
Eric, why do you bother wasting time on someone so obviously divorced from reality as Snorbert Zangox?
[Response: Because reasonable but uninformed people might take him seriously, and his questions are not — on the face of it — necessarily all off base.–eric]
#122’s response to the question, “why, in spite of the favorable conditions did the growth of trees abate during the late 20th century.” is
Well, land use changes… or are you unaware that we cut down forests to make cities and farmland?
THAT is an answer? I am sure that there are a lot of variables which affect tree growth (which bothers me about all tree ring data in general) but usually, removing other trees (all other things being equal) positively affects growth, as I assume higher CO2 levels would as well. Has there been any corroboration from foresters that tree growth has slowed?
[Response: No, growth hasn’t slowed, in general. See e.g. here.–eric]
On a separate note, I found Hansen’s statement, that for all he knows, we could be entering another Maunder Minimum, er “interesting.” Should that scenario unfold, we would know beyond a reasonable doubt that Gaia has a sense of humor.
Daniel C. Goodwin says
Re 143: “I suspect that if the projections are correct – then nuclear power will be the only way that society can not implode. From what I have read here – that may be Prof. Hansen’s view too.”
In “Storms of my Grandchildren” Hansen speaks out loud and clear in favor of 3rd and 4th generation nuclear power – even to the point of expressing anger about the unreasoning, unconditional opposition to nuclear power that he sees in otherwise thoughtful people.