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Six Degrees

Filed under: — eric @ 25 November 2007

“Alarmism” is a term that gets bandied about a lot. It is often said that one should not call out “fire” in a crowded building. But it really depends, one might say, on whether the “calling out” is done in such a way as to simultaneously prevent a stampede and prevent anyone getting burned.

This riddle was very much on my mind as I sat down to write my thoughts on Mark Lynas’s book, Six Degrees: Our Future on a Hotter Planet (London: Fourth Estate, 2007). I don’t read much popular science literature, and I doubt I would have read this book if I hadn’t made the mistake of referring to it (in a negative manner) in the comments section of a RealClimate post. I don’t think my error was very grave. What I actually said was that if what I had heard about the book from the press materials were true, then the book was probably alarmist and not worth reading. But I don’t blame the author for asking me to read the book and see for myself. He said that the press (in this case Sunday Times (London)) had misconstrued what he says in the book, and he assured me that is was all based on very careful review of the scientific literature. I was thus both curious and obligated to read the book.

Mark Lynas will no doubt be pleased that I very much like the book. To be sure, it is alarming, but the question of whether it is alarmist is a more difficult one, and I don’t think the answer lies in debating the book. Rather, it lies in looking closely at the underlying science the book builds on. I don’t intend to do that here, but I do think that all climate scientists (particularly those that talk to the public) ought to read this book, and ask themselves a question. I’ll get to that question at the end, after saying a bit more about the book.

Six Degrees, as the title suggests, is comprised of six main chapters (plus an introduction and a conclusion). Each of the main chapters examine what the earth might look like as we raise the planet’s temperature by 1o, 2o, etc. degrees Celsius, based on what the scientific literature has to say about it. Laying out the book this way makes for a good logical progression of ideas, and a fair bit of suspense. Very few people, Lynas says, have got “the slightest idea what two, four or six degrees of average warming actually means in reality, and I’m sure he is right.

In Chapter 1, at 1o, we have predictions of, for example, an annually ice free Arctic ocean. Yes, quite plausible and supported by the literature, and perhaps occurring a little sooner than expected. At 2o, we have, “so whilst southern China can expect more flooding as the two-degree line is approached, the oceanic time lag means that it may take much longer for the rain-bearing summer monsoon to reach the drought-stricken north.” Yes, certainly plausible based on the studies Lynas cites. At 4o, we have “with global sea levels half a meter or more above current levels, [the Egyptian city of] Alexandria’s long lifespan will be drawing to a close. Even in today’s climate, a substantial part of the city lies below sea level, and by the latter part of this century a terminal inundation will have begun. … a rise in sea levels of 50 cm would displace 1.5 million people and cause $35 billion of damage.” Alarmist? Hardly. A 50 cm rise in sea level, is well within the conservative IPCC projections, even for temperature rises less than four degrees.

At 5o and 6o, the book really does start to sound alarmist, with the analogy to Dante’s Inferno – used to good literary effect throughout the book – coming very much to the fore. At five degrees, we have “an entirely new planet is coming into being – one largely unrecognizable from the Earth we know today. At six degrees, “… the pump is primed … not for flourishing palm trees in Alaska, but for the worst of all earthly outcomes: mass extinction.”

Aha, say the skeptics! It is alarmist after all. But is it? Lynas’s reference to the “entirely different planet” actually refers to the fact that at five degrees, the “remaining ice sheets are eventually eliminated from both poles.” That’s entirely true. And unlike in Gore’s discussion of sea level in Inconvenient Truth Lynas does emphasize the long timescales (thousands of years) in this case. Furthermore, there is published research that raises the likelihood of the significant loss of ice sheets at lower temperatures, and Lynas could have claimed certainty of a disappearing Greenland ice sheet in an earlier chapter. That he doesn’t do that is characteristic of the book: it doesn’t tend to go beyond the published literature. This is what Lynas claims at the outset — “all of the material in the book comes from the peer-reviewed scientific literature” – and I think he does an admirable job.

And that brings us back to the question I promised to raise at the beginning, which is this:

If a reading of the published scientific literature paints such a frightening picture of the future as Six Degrees suggests – even while it honestly represents that literature – then are we being too provocative in the way we write our scientific papers? Or are we being too cautious in the way we talk about the implications of the results?

173 Responses to “Six Degrees”

  1. 51
    Lost Horizon says:

    As I look at the current satellite shots of the pass season’s artic ice melt rate increase, I’m struck by the fact that none of the major, generally accepted climate models reflect this Reality. None even came close to predicting this ice melt increase.

    Is this fact ‘Alarmist’?

    It is breath-taking.

    Imagine if the major climate modelers were made to appear in a public forum and had to jigger their respective mathmatical ‘babies’ until they reflected current observable artic ice melt increases, at .5 degrees(C).

    Then have each of them run their models forward to 2 degrees(C) like the IPCC is currently pushing as ‘acceptable’ compromise.

    I can just hear the Giant Sucking Sound (GSS) it would produce from the assembled masses as they take a Big Gulp (BG) of ‘awsome’ and then faint from the vapors.

    Would such a re-tooling of the present crop of climate models reflecting current observable phenomenon be considered ‘alarmist’?

    Nervous Nellies would no doubt plug-up their ears with their fingers and go la-la-la-I-can’t-hear-you while ‘climate holocaust deniers’ would protest too much that the models were unfairly Forced to conform to Reality.

    Positive feedback loops are a real killer when they finally start their ‘compounding interest’ boogy. There is no historic example close to the CO2 increases in the past two centuries or so on the late great planet Earth, short of a big fat asteroid or a mega volcanic event.

    Everyone is whistling past the graveyard if you think that such a CO2 increase into the self-regulating environment of a planet is not going to produce a rather ferocious positive feedback reaction.

  2. 52
    Jeffrey Davis says:

    Please: Not for publication on the blog.

    Lord Monckton has published a response to a Kentucky newspaper editorial:

    “The IPCC says the “radiative forcing” from CO2 rose by 20 percent between 1995 and 2005. Yet in that period the atmospheric concentration of CO2 rose from 360 to 378 parts per million — just 5 percent. The radiative forcing effect — which causes temperature change — rose by only 1 percent. That’s a 20-fold exaggeration by the IPCC.”

    Now, some of that seems gibberish. He invents a separate category — radiative forcing effect — and attempts a multiplicative compounding of an “error”, but how DID the IPCC get a 20% increase in radiative forcing with a 5% increase in concentration?

  3. 53
    Ray Ladbury says:

    Gareth Evans said “There are still many sceptics out there, however, including some of our very best scientists (outside of climate science).”

    Best scientists? Such as… As near as I can see most of the so-called skeptics sufficiently arrogant to think they are experts in everything are second rate or no longer active even in their own fields. When there is not a single professional society of scientists that dissents from the consensus, you really have to wonder about those who hold out on the basis of flawed understanding.

    I agree that the Gulf Stream conern is probably overblown. We could see interruptions of the Gulf Stream for a couple of years at a time, though, and that would be catastrophic in Europe.

  4. 54
    henning says:

    I don’t think it really matters whether we call it alarmism or not. The whole point of the book seems to be getting people to think about what the world might look like if we don’t act. As such it eventually stretches the scientific basis here and there (just like Gore) without really telling any lies and thats fine for an author. However I would prefer scientists to only report what they found out without voicing hidden personal opinion or bias as far as humanly possible. The discussion about IPCC reports being somewhat too cautious or too alarming when commented by scientists worries me. I’d like to think that at least the Report itself (not the summary) simply includes scientific facts and I trust this to be the case.
    Eric, you ask whether you’re being too cautious when talking about the implications of the results of your papers? Maybe you can give an example here. My feeling is, that as a scientist you write papers about things you scientifically examined and you should not talk about implications unless you examined them scientifically as well. Otherwise it would just be a personal opinion and should be clearly identified as such. But maybe I misunderstand.

  5. 55
    henning says:

    @Lost Horizon
    I would consider it alarmism IF an event such as the exceptional retreat of arctic sea ice this summer would lead to the conclusion that all models are flawed or conservative without clearly understanding, what exactly caused the retreat. AFAIK this understanding is not yet complete.

  6. 56

    Edward Greisch repeats an already refuted factoid:

    [[The truth is that a coal fired power plant puts 100 times as much radiation into your environment as the nuclear power plant. The truth is also that natural background radiation is 10 times what you get from a coal fired power plant.] ]]

    The truth is also that the estimate for the nuclear plant doesn’t include the “unplanned releases” which plague every real nuclear plant in the world.

  7. 57

    Susanne Munk (#48) wrote:

    I enjoyed reading this entry very much but it made me wonder: How would you define mean temperature for an entire planet and how would you test if it is changing? Perhaps this has been discussed here before?

    In principle, it would be defined as the integral over the surface area, then integrated over the time period under consideration, then divided by the product of the surface area times the time.

    Now obviously we can’t calculate it quite that way. Instead you have a finite number of measurements, but then there is some sort interpolation which is used. But this will be a little bit off. However, with the law of large numbers, we know that the larger the number of measurements the closer we get to the true average, and in fact the true average can be known with much greater accuracy than the individual measurements.

    To see why, throw a dice. Now you that dice can have any value between 1 and 6. There is a great deal of uncertainty. But throw the dice repeatedly, and you know that the more times you throw it, the average value of all the throws will tend to get closer and closer to 3.5.

  8. 58
    Walt Bennett says:

    As a layman, I can say that the problem is simple: how to be definitive amidst scientific uncertainty.

    There is no simple solution.

    For one thing, we have long since passed the point where every conceivable scenario has been ‘predicted’, and most of those have been ‘based on’ what the author considers convincing evidence. Shouting louder will only have the effect of making the shouter seem more desperate. I for one do not automatically interpret desperation as a sign that the person is correct. He or she may be; then again, he or she may be delusional.

    There will never be a public consensus on either the warming or the solutions to it. That is a dream that it is safe to let die. There are simply too many stakeholders. Perhaps the largest constituency of stakeholders are those who are past the mid-point of their lives and simply want a peaceful retirement. They hope to die on a planet that resembles the planet they were born on.

    There was a thread not long ago on the topic of geo-engineering. I took the AGHAST! position that we don’t know near enough about climate to imagine that we can engineer it, or even to engineer a desired range of global temperature. I received some support for that position.

    Since then, I have done a 180. I now believe that we must develop plausible geo-engineering solutions, and the reason is precisely that I believe the science. I believe the radiative forcing potential of CO2 is well understood. I believe that positive feedbacks are decently understood. I believe that the last two years are evidence that science has those things right.

    I am certain that humankind will not reduce productivity in order to reduce greenhouse emissions. I am certain we will continue transforming the land, which is an independent issue from CO2 but every bit as much of a concern. Because I believe these practices will continue, I thus believe that the only available solutions will be those which “solve” the warming by means of reducing surface insolation (or possibly by scrubbing the CO2).

    In other words, I believe it is too late for this discussion, and it was probably unsolvable in the first place. “Six Degrees” will find its place, and those who believe in AGW will defend it; those who do not will dismiss it, or look for the smallest, exploitable flaws.

    That is the one assured outcome in all of this.

  9. 59
    Hank Roberts says:

    Lynas isn’t alarmist — he’s awakeist.
    We need more awake.

  10. 60
    Mark R says:

    The scientific community is far too cautious, hestitant, and retiring. Alarm bells should be ringing out all over the place. If scientists do not feel like this is proper behavior for a disciplined and humble community, then most human beings will remain complacent, ignorant, and resistant. Meanwhile, the “scientist” will tentatively tug on the world’s sleeve, saying in a weak voice “Um, excuse me…um, excuse me…” or else later will take off his proverbial thick-framed glasses and announce in a grave voice, “I’m afraid it’s too late to do anything.” If the scientific community must shelter behind people like James Hansen, or Al Gore by proxy, so be it, but absolutely nothing will be done in time. In fact, we already are out of time (eight wasted years is the final lost opportunity), and if everyone who knows this doesn’t start shouting about it, we’ll face even worse chaos.

  11. 61
    Lynn Vincentnathan says:

    Well, obviously there is not nearly enough alarmism over GW, or we would have been reducing, not increasing our GHG emissions.

    The evidence is in (our increasing emissions) – there just isn’t enough alarmism to even slightly budge that growing elephant in the room (GW) that no one talks about.

    I’m sort of hoping beyond hope that SIX DEGREES might jar people into sensibly reducing their emissions.

    It’s weird, but one just can’t get alarmist enough re GW. Words (even red-faced screaming them) utterly fail us about the enormity of this alarming problem.

  12. 62
    Keith says:

    Nice post. I actually believe that it’s this type of discussion that is at the very core of this debate. A lay person looks at this kind of book, simply in a binary fashion; is the book right or wrong? Is the science right or wrong? I think as scientists we have to remember that the vast majority of general population has virtually no scientific knowledge past maybe knowing a few elements from the periodic table. So when we make statements about climate change (skeptics or not) they are simply not in a position to assess the science. I look at my own background as a chemist and remind myself that when I first started reading this site I was a denier and as I have learned I’d reclasify myself as a skeptical believer (there’s a new one). But I actually did maths at university and have a scientific education so I can at least try to work my way through the science. Most people don’t.

    One of the most significant changes of the last 30 years (in my opinion) is the increasing gulf in knowledge between scientists and the general public. This has led to all sorts of terrible effects where science is misrepresented or miscommunicated and people lose confidence in our objectivity. You only have to witness the numerous public health panics over every vaccine and medication known to man, food scares and so forth. Sadly, we’re now in a position where we simply have to get this one right. If we’re wrong and things get REALLY bad, worse than predicted, then science is going to be right in the firing line. As scientists we have to get this right. Personally, I see more damage in doing nothing about climate change. There’s very little to lose if we can become more energy efficient and use resources more wisely. Absolutely nothing. On the other hand if it really is going to get bad we need to get our socks on and do some work.

    This is why this book is far from alarmist. It gives, in effect, simple examples of what might happen given certain changes in temperature. It’s as close to binary as we’re going to get. The way I look at it, if I’m driving a 100mpg car in 20 years and catastrophic climate change doesn’t happen I’m not exactly going to get pissed. I’m going to pat myself on the back for doing a great job. If, however, the predictions are worse and I really needed a 300mpg car to avoid catastrophe then I’m going to be pissed. Why didn’t we try harder. Whay didn’t those damn scientists tell me how bad it could get!

    This book is exactly the type of thing that will make people think about the consequences. We have to be pragmatic and communicate the value of that approach. Risk vs benefit.

    So this is science’s great chance to be right. The models (whatever I think of them) have to to be spot on or we’re going to be in a big mess and there are going to be a great number of people asking why we didn’t get it right.

  13. 63
    George Robinson says:

    I have read this book, early this spring when it first came out, so the IPCC report of early this year is not taken into account. Things have happened this year that have surprised even some of the sceptics, well almost anyway. The melting of the arctic ice during the summer months has surprised most people, and the opening of the NW passage, and even the NE passage passable as well has really caught everyone with their pants down. Some are now forecasting the the summer ice could disappear by 2015.
    However, the melting of the Arctic sea ice will not cause any concern, so Florida is safe for the time being.
    More disturbing is the increased rate of melt of the Greenland ice sheet. All glaciers on both west and east coasts are melting at a rate thought not possible just a few years ago. One, the Jacobshavn breen, responsible for about 7% of the icecaps discharge this year was discharging ice at the rate of 35 billion tons a year, which adds up to approx 500 billion tons from the entire icecap in one year.. The more the icecap recedes the more land area is exposed to sunlight, nore ice melts, more land exposed and so it continues.
    The oceans around Spitzbergeb have been ice free during the past 2 winters, ice which is normally several meters thick. The reason for this is the changing of the direction of the G.S. It is travelling futher north, and higher up towards the surface of the ocean, so that when the temperature should have been -2c it was +2c. Even the land based glaciers on Spitzbergen are also affected.
    The maritime glaciers of Norway have receded on all fronts, to such an extent that they are at their “smallest” since the last ice age. These glaciers were thought not to be affected so soon, but with the winter season becoming shorter and shorter, snowfalls are not replacing icelosses. Permafrost in Norway and Sweden are also thawing, the tree line is getting higher up the mountains.

  14. 64
    Jamey says:

    If we are in a theater on fire, it is a threat today – a defined threat. Saying, “This theater could burn down in 30 seconds, run now,” is alarmist. It is very unlikely to happen that fast and we are just trying to cause instant motivation. We can all agree on that because we can judge the time it will take, at least roughly.

    If we are in a theater that will slowly catch on fire and burn down over the next three hours, then this is a threat for the future. The statement of “burning down in the next three hours, run” is not alarmist – we have no sense of how to assess risk on a time scale of years or decades. “I could stay and see the whole movie and hope that the roof over my head doesn’t fall before it is over.”

    Now, how do you stop that person from sitting still? Be being calm or frantic or in-between?

    I have read Lovelock’s “Revenge of Gaia”, Pearce’s “With Speed and Violence”, and now Ward’s “Under a Green Sky” in the past year. All are geared for the lay reader and are more likely to be called alarmist, but I have found a disturbing trend in the experts in these books. In their cited scientific papers, these experts write in measured tones, but in interviews, those same scientists are much more likely to be pessimistic and leaning towards the more extreme scenarios. (Under a Green Sky’s last chapter is fantastic and horrifying at the same time. But plausible.)

    Maybe we are the problem – we aren’t being upfront enough about our insights into the changes and the models. How many of the “99% of climate scientists who agree that global warming is happening?” would take the next step and further explain which of the IPCC scenarios they think most likely? How many of us would come in as A1FI (worst case, “business as usual”)?

  15. 65
    Jim Eager says:

    Re Cody Griffin @42:”Morover, since we all know that climate change has happened hundreds even thousands of times in the past, then what makes us think this one time in earth’s long established history this episode of warming is man’s fault?…
    Cody Griffin

    Same old denialist slights of hand misdirection (humans did not cause past warming events) and untruths (climatologists do not focus exclusively on just the past 600,000 years).

    And from DeSmogBlog @ :

    “If indeed man is causing this “pitance” of warming to day…then what caused it 25,000 years ago that resulted in glaciers retreating from TEXAS to Canada? Was it Cro-Magnon and his coal fired electric plants?
    The earth has a long well established history of warming and cooling. The earth has undergone numerous major climate changes long before man was even present. To believe man is the cause or gloabl warming today when he could not have been hundreds of times before is folly…sheer folly.
    Cody Griffin
    Certified Professional Geologist”

    So, Cody, which is it, Certified Professional Geologist, or Paleo-climatologist?
    Seriously, no hits using Google Scholar for either.
    Petroleum geologist, perhaps?

  16. 66
    Charles Muller says:

    #61 On this point, do we have any global estimation of Greenland and Antarctica ice melting since the first “salvo” of GRACE results fall 2006 / winter 2007 (Chen, Velicogna, etc.) ?

    Anyway, I suppose sea-level should reflect this trend, but Jason-Topex-Poseidon most recent data are not particularly… alarming. On this graph from U Colorado, I sea no acceleration for the rate of sea-level rise 2002-2007 when compared to the previous years of satellite measurement. I would even say that 2007 seems a quiet year.

    Of course, we may suppose a non linear evolution, an exponential rate of melting, a tipping point… but the frontier between alarming and alarmist is then not clear until a physical model sustains these hypothesis.

  17. 67
    Lynn Vincentnathan says:

    RE #58, and the scientific community being too cautious. I think scientists have to do what they’ve always done – work hard at science, and avoid the false positive; that is, avoiding claims when they are false — which requires scientists to have high confidence in something, say 90 or 95%, in order to make a claim.

    The onus is on “the people” for not shouting and screaming and ringing alarm bells over this issue, while seriously reducing their GHGs — especially their leaders and policy-makers. We lay people do not need 95% confidence that a lump is cancerous to have it surgically removed, nor do we need 95% confidence that GW is happening and may reach 6C and really wipe out a lot of earth’s biota (including people) to reduce our GHGs by 75% cost-effectively (which is possible with off-the-shelf-technology, and would make sense, even on money-saving merit alone). And it doesn’t take a rocket scientist to screw in a compact fluorescent bulb (tho I realize some denialists may need a bit of help :) ).

  18. 68
    Aaron Lewis says:

    Most “climatologists” are young, and have spent much of their lives in school, in front of a computer terminal or with their nose in a book. That is good. It is the ONLY way they could learn that mass of stuff that they need to know in order to be a good climatologist. However, it leaves them without the broad diversity of experience that they need to appreciate the implications of global warming.

    A few centimeters of sea level rise does not mean much to an atmospheric physicist sitting at NCAR. It does mean something to a hydrologist fighting salt water intrusions into drinking water supplies. It means something else to civil engineers working on utility corrosion issues at petrochemical plant on the Gulf Coast. It means something else to a foundations engineer dealing with settlement as water levels change under our coastal cities. It means something else to someone working on beach erosion, or sea walls or wild life issues or costal zoning. The climatologist cannot be expected to understand all of the implications of his work. He certainly cannot be expected to address all of these issues. If he tried to, he would not have time to do any climatology.

    Then, Climatologists have been too cautious. The last IPCC report offered a lower bound to lea level rise, but no upper bound. That is unacceptable. Think about that from the viewpoint of all those engineers in the previous paragraph. They are more concerned about the real upper bound of sea level rise, than they are about the lower bound. Economic studies need to reflect the actual cost of dealing with the full upper bound of climate effects rather than the lower bound. An economic study using the lower bound number must be biased toward “BAU.” The critical number is. “How big a sea level change could we have in the next 100 & 200 year periods including all ice dynamics and everything?” THE IPCC was derelict in its duty by NOT offering any up such numbers.

    While many climatologists are excellent technical writers, they are so busy writing for each other, that they have not effectively communicated with other groups and fields that are trained to appreciate the implications of global warming. Climatologists need to write more persuasively. They need to remind people that they are very conservatively, and are NOT addressing the multitude of issues and problems that will arise from global warming. People need to understand that the purpose and viewpoint of peer reviewed papers on climate in a science journal is different from that in an engineering journal. The unstated assumptions are different.

    Some funding organizations have focused on the pure science, without asking the obvious questions about the implications for society that are clearly posed, but not answered by the basic science. Some of the public statements by the heads of these organizations suggest that they are in denial of the implications of the science. This suggests that the climatologists have not effectively communicated to their own managers.

    The global warming situation needs to be clearly communicated the engineering community. The engineers will then generate another set of numbers that can be used for risk management.

    Those numbers can be used for economic cost studies. Then those risk management numbers should be communicated to policy makers. This is not the job of the climatologists. However, full communication of results IS part of the job of the organization managers and funding organizations.

  19. 69
    Lynn Vincentnathan says:

    RE #9 and the possibility of reaching 6C warming by 2100, I think the more important point in SIX DEGREES is that if we reach 3C warming (whether by 2050 or 2100 or 2150 or later), this will almost ensure that there will be 4C warming, which will almost ensure there will be 5C warming, which will almost ensure 6C warming…..sometime down the line.

    So in that sense, it’s 3C that is really really scary. We’ve got to stop well before we reach 3C, preferrably before 2C. Failure to halt this is not an option!

    And BTW, the book can be ordered (at high shipping price) through

  20. 70
    Dan W says:

    Re (#52), Monckton Editorial:

    Did the IPCC really say “the “radiative forcing” from CO2 rose by 20 percent between 1995 and 2005”? This doesn’t sound like something “they” would say. I don’t recall reading it in the AR4 (but that doesn’t mean much). I find it hard to believe it is there some place. Perhaps they said the rate of change of the increase of radiative forcing increased by 20%?

    Does anyone recall seeing this supposed statement by the IPCC? Or is Monckton making things up?

  21. 71
    Joe Duck says:

    Nick wrote (and Tim this is an attempt to answer your question as well):
    Of course technology will change over the decade (I would be interested to hear whether Joe expects “dramatic” changes over that period, which is the one in which we have to take serious action to prevent likely disaster …

    Nick I don’t accept the premise that disaster is looming though I agree things could get much worse if the most dire scenarios come to pass. However the science suggests to me disaster is not looming and that the IPCC projections about warming and ice effects should be accepted as reasonable. I need to read more but I’m clost to rejecting the notion of many here that IPCC does not adequately address uncertainties in those projections. I think the IPCC assessments, rather than the unlikely abrupt climate change events, are what we should base our policies upon.

    Why? This relates to your technology question. 10 years will bring a lot of technology improvements, as well as much better climate modelling computer power. Conscious computing, which is 10-20 years away, may bring a climate model that actually has a high level of real-time predictive power. This would settle a lot of the key questions regarding ice changes and the pesky lag issues surrounding CO2 and temperature, which make good projectioons of even a few year time horizon impossible for the current models.

    I doubt it’ll bring a solution to CO2 increases which I think will continue, mostly due to China’s massive development projects and reluctance to curb CO2.

    Eric this is a good, provocative post dude:
    In your opinion what is a good standard for “alarmism”?
    If Lynas is *not* reasonably called an alarmist, then why are so many here so hard on guys like Pielke and Lindzen on the other side of the climate interpretation spectrum?

  22. 72
    Jerry Toman says:

    Re: #52 (Lay person comment)

    You are forgetting that “radiative forcing” is defined relative to the pre-industrial level of CO2, which is taken as 280 ppm. The higher CO2 ppms “force” the surface temperature to deviate from the value that prevailed then in order to reach a new thermal equilibrium with the incoming radiation.

    So you would compare the change in the ratio of those values if it were linear (+22%) or more accurately by the change in ratio of their logs (log(360/280)divided by log(378/280)) or about 19.5%

    Tell me I haven’t screwed up the math or the explanation somehow.

  23. 73
    Mauri Pelto says:

    Excellent question and submissions in this thread. If I think back to the first global warming oriented conference I attended in 1984 at Northwestern and then review in mind the progression of the discussion with respect to glaciers, I would have to say we were being cautious as glaciologists looking at likely changes and the rate that they would occur. This is a conclusion in hindsight now having seen the loss of some substantial ice shelves, the acceleration of some of the the most prominent glaciers in Greenland and Anatractica, the disappearance of 5 of the 47 glacier I began observing 25 years ago in the North Cascades, the retreat of every single one of the more than 100 Swiss glaciers observed in 2005 etc. So today I would tend to think that the scientific community I interact with is being too cautious just as we were then. With respect to the earlier question about moulins and the Greenland Ice Sheet. More water delivered to the base of the Greenland Ice Sheet can accelerate its outlet glaciers somewhat due to more lubrication of the bed. However, there has been for sometime considerable meltwater delivered to the bed of this ice sheet. If you look at early maps of the ice sheet from the 1950’s plenty of meltwater ponds are shown on the ice sheet surface near the margin. As a result though an increase in moulins size and number indicate a bit more melt, and would tend to speed the ice sheet up some, it is not a new dynamic shift in the behavior of the outlet glaciers that alone would lead to a rapid diminution of the ice sheet.

  24. 74

    Scientists are human too ( aren’t they?). Why can’t they,then, when speaking for themselves, give a danger warning when they feel it’s warranted?

    When the latest IPCC report says “Eleven of the last twelve years rank among the warmest years in the instrumental record of global surface temperature(note-the average of near-surface air temperature over land and sea surface temperature)(since 1850).”, I, for one, hear the sound of the alarm clock going off. It’s time to wake up and get to work. 11 our of 12! What are the odds of coincidence?

    It seems that we can use a few alarmists right now to counter-balance the over complacency of high level decision makers right in our backyard (the U.S.).

    Was Paul Revere an alarmist or a realist? (“Ready to ride and spread the alarm to every middlesex and farm”- Longfellow). It was a call to arms then and a similar kind of action is needed today.

  25. 75
    Anders Lundqvist says:

    I have read the book – or at least most of it. The chapters 5 and 6 were almost too painful and dispair-evoking, so I have saved most of them for later. But I do recommend the book to everyone who is seriously interested in the climate crisis.
    What seems more and more evident is that we are not cutting off the branch that we are sitting on – we are cutting of the branch our grandchildren’s children would have liked to sit on. And the branch that we leave for them might not be at all as comfortable as our one.

  26. 76
    Ian Perrin says:

    If Gareth Evans (#53) is correct in saying ‘there is not a single professional society of scientists that dissents from the consensus’, then RC has fulfilled its primary purpose and done so magnificently.

    The main body of your audience is active formally or informally in passing on the news (good or bad) to the world at large. We have come to rely on your take of the science involved, together with input from outside contributors and your comments upon that input.

    Our needs are different now. We need you to continue to update us on the science, but as possible effects of AGW begin to impact us (e.g. the Arctic in summer 2007), we would value your opinion on the major events and how they fit with the scenarios generated by GCMs. We understand that one series of events of this nature does not constitute a trend, but the magnitude of the anomalies rings alarm bells in most of us. We naturally come to RC to see whether you are also alarmed and why. Informed comment from RC, with the necessary caveats, would be welcome.

    Yesterday, the BBC News 24 service told us “The number of weather-related disasters has quadrupled over the past 20 years and the world should do more to prepare for them, the aid agency Oxfam says.”

    Reading deeper, this looks to be AGW related and it looks like a trend. Again, I am alarmed by the scale. I want to convey that alarm to those who respect my opinion, but I do not want to be labelled alarmist. I need the best opinion I can get, so I turn to RC. It would help me if you could pick what are significant events in your opinion and provide us with informed analysis, even if (to paraphrase) all you can say is “this is worrying, we need to analyse it further”.

  27. 77
    Richard Ordway says:

    Keith wrote: “So this is science’s great chance to be right”.

    Hmmm, mainstream science not gotten it right before? I’d like to add that mainstream science “got it right” about the ozone hole problem…it was a stunning success story (when everything worked (basically) as it should have) and was listed at about a 95% confidence level, I believe.

  28. 78
    Timo Hämeranta says:

    About sea level rise.

    The IPCC AR4 2007 states

    “Global average sea level rose at an average rate of 1.8 [1.3 to 2.3] mm per year over 1961 to 2003. The rate was faster over 1993 to 2003: about 3.1 [2.4 to 3.8]mm per year. Whether the faster rate for 1993 to 2003 reflects decadal variability or an increase in the longer term trend is unclear.”

    This estimation is already outdated.

    In more precise and up-to-date calculations the alleged faster sea level rise has been shown to be SLOWER, reduced to 1.31 ± 0.30 mm/yr, please see:

    Wöppelmann, G., B. Martin Miguez, M.-N. Bouin, and Z. Altamimi, 2007. Geocentric sea-level trend estimates from GPS analyses at relevant tide gauges world-wide. Global and Planetary Change Vol. 57, No 3-4, pp. 396-406, June 2007

    Wöppelmann et al. note that “two important problems arise when using tide gauges to estimate the rate of global sea-level rise. The first is the fact that tide gauges measure sea level relative to a point attached to the land which can move vertically at rates comparable to the long-term sea-level signal. The second problem is the spatial distribution of the tide gauges, in particular those with long records, which are restricted to the coastlines”.

    These and other new studies raise numerous new questions, besides sea level rise and oceans heat content, e.g. about water cycle, Antarctica, Greenland & glacier melting, SW & LW radiation penetrating into the oceans, ocean mixing & circulation, etc, etc, etc which all might be more or less wrong in the IPCC models.

  29. 79
    Chris C says:

    RE #42

    For a paleoclimatologist, this is really a bit bizarre. For one thing, I don’t know if people are “ignoring” the rest of Earth’s history (ex. see Royer on CO2 as a driver over the Phanerozoic). However,it is also nice to use a paleoenvironment in which planetary conditions are much like how they are now…which is not the case the farther back you go with plate tectonics, evolution of the air and sea, etc. Would you rather model 2x CO2 in Holocene-like conditions, or 2x CO2 is a martian atmosphere before testifying to congress on where we are likely headed? Paleoclimate is very important to place where we are now, and where we are headed into context, and you can see ch. 6 in the IPCC 2007 WG1 report yourself.

    Next, climate is generally stable in the absence of external perturbation; past climate changes did not just go off by themselves, sometihng caused it. It could be Milkanovitch cycles, solar dimming, an asteroid, Siberian traps, greenhouse gas release, etc. Actually, most changes involved greenhouse gases as suspects (so your question could be rephrased- is the greenhouse physics different now than it was all thoughout Earth’s history?). This is why there is a detection and attribution process, so we can avoid logical fallacies and the popular claims by secondary sources that past fluctuations must mean humans aren’t a factor.

  30. 80
    Chris C says:


    This is why you should read the book. The review got Lynas’ thoughts wrong.

  31. 81
    Lynn Vincentnathan says:

    RE #23 & “the present debate centers on whether the next century can shift it further by the length of Vermont, or Illinois…”

    What if we build freeways and don’t let those creatures move north? What about the creatures in the arctic areas that have nowhere to go (I understand some migrating species are just taking over and pushing them into extinction)? What about the heat sucking up a lot of moisture into the atmosphere, dehydrating the land (the vertical shift) — causing droughts, and floods in the midst of droughts, and wild fires?

    Okay, so our agri belt goes north somehow (and let’s assume nothing bad happens to it — and we know there’s going to be more droughts & floods), if one gets a globe rather than a map, one thing becomes immediately apparent — there’s less area up north. The promised land is a smaller land.

    Now I don’t really know what I’m talking about, but these things just came to mind as possibilities that make me think that global warming might be a bit more troublesome than moving from St. Louis to Chicago.

  32. 82

    Jerry Toman (#68) wrote:

    So you would compare the change in the ratio of those values if it were linear (+22%) or more accurately by the change in ratio of their logs (log(360/280)divided by log(378/280)) or about 19.5%

    I believe you did the math right. It was only how you expressed it that was a little wonky. I would divide log(378/280) by log(360/280), subtract 1, then multiply by a hundred to get the percent.

    In any case, better than I would have done right off the bat, I believe.

  33. 83
    Charles Muller says:

    I just read Hansen et al. article published in 1981 in Science (for other reasons that the present discussion). It predicts a 2.5-4.5 °C warming for 21st century according to fossil fuel proportion in energy use. It says precisely that a 2°C global warming would be enough for a 5°C warming of the West Antarctica Ice Sheet, whose melting could be rapid (“requiring a century or less and causing a sea level rise of 5 to 6m” that “would flood 25% of Louisiana and Florida”).

    Well, 1981, 26 yrs ago: hard to say some scientists are “too cautious” in the way they present human consequences of global warming. And reading these “historical” papers on AGW as an emergent problematic gives a strange impression of déjà vu.

    Hansen paper :

  34. 84

    Andrew (#8) – The basic argument against Greenland being lubricated by moulins and sliding off into the ocean is that the weight of the ice has created a topographic bowl whose center is below sea level. If Greenland’s ice were perfectly free to slide, most of it would stay where it was. The animation of moulins in An Inconvenient Truth gives a correct representation of the underlying topography but doesn’t provide a mechanism for getting the ice cap to slide uphill.

  35. 85
    Jim Dukelow says:

    In Comment #44, Nick Gotts wrote:

    “You might also have mentioned the domestic robots, artificial superintelligences, bases on the moon and Mars, electricity “too cheap to meter” (from nuclear power), and the cure for cancer.”

    The “too cheap too meter” comment was made by Admiral Lewis Strauss in the mid-1950’s to a group of science writers. Strauss was Chairman of the Atomic Energy Commission and was an Admiral by virtue of his work on war production during the Second World War. He was actually a financier, not an engineer or a technical person of any sort. To get a handle on what technically-qualified people were saying about the economics of nuclear power at the same time, Real Climate readers can visit the web page:

    I might also note that in big cities, like New York, where perhaps Strauss lived, steam heat and water and, sometimes, electricity, delivered to apartment dwellers, are “too cheap to meter” and the costs are simply averaged out and folded into the rents. That may have been what Strauss was thinking as he shot off his mouth.

    In Comment #55 Barton Paul Levinson wrote:

    “Edward Greisch repeats an already refuted factoid:

    [[The truth is that a coal fired power plant puts 100 times as much radiation into your environment as the nuclear power plant. The truth is also that natural background radiation is 10 times what you get from a coal fired power plant.] ]]

    The truth is also that the estimate for the nuclear plant doesn’t include the “unplanned releases” which plague every real nuclear plant in the world.”

    Well, I missed the “already refutation” of Greisch’s factual factoid, but Levenson can enlighten us with an example.

    Energy Northwest’s WNP-2 nuclear plant is visible out my window, about 30 miles northeast. It has been in operation for some twenty years. The Boardman coal plant, 60 miles south, has been in operation about the same length of time. I take an active interest in both, but am unaware of any unplanned releases — those things Levenson assures us plague “every” nuclear plant in the world, that would bring radiation releases of WNP-2 anywhere near the radiation sent up the stack of the Boardman plant every working day. Also to the point and unmentioned by Levenson, releases from Boardman go right up into the air for everyone around the plant to breathe. Releases, planned or unplanned, from WNP-2 typically have much more tortuous pathways before they reach me or anyone else. In addition, the radiation releases from Boardman are a small fraction of Boardman’s insult to the environment, whereas the smaller radiation releases from WNP-2 are virtually the sum total of its insult to the environment.

    Waiting for a detailed list of WNP-2’s unplanned releases. . . .

    Best regards.

  36. 86

    Lynn Vincentnathan (#66) wrote:

    RE [Caspar Henderson] #9 and the possibility of reaching 6C warming by 2100, I think the more important point in SIX DEGREES is that if we reach 3C warming (whether by 2050 or 2100 or 2150 or later), this will almost ensure that there will be 4C warming, which will almost ensure there will be 5C warming, which will almost ensure 6C warming…..sometime down the line.

    Barring butterflies, the feedback should be a monotonously increasing function of our emissions, assuming a constant rate of emissions over a given period of time. Likewise, I would suspect that given a constant total emissions, given a constant rate of emissions, the feedback will be a montonously increasing function of the rate of emission. 3C fast-feedback might imply 6C total feedback (where we are including the slow-feedbacks), but 3C does not imply 4C which implies 5C which implies 6C.

  37. 87
    ME says:

    To echo #16, one of the things that turned around the public perception of nuclear weapons were the publications on the possibility of nuclear winter. My own uninformed opinion is that such predictions were probably alarmist. The idea that a nuclear winter will follow nuclear war is pretty firmly ingrained in the public mind, despite the fact that nobody really knows what would happen.

    In the same way, I think that there is room for sober analyses, and there is room for being cautious, but there also needs to be an idea of very blatant and graphic results of global warming to help people get a handle on the possible consequences.

    Today, people don’t really understand how bad things can get . . . small sea level rises that flood a few faraway cities just don’t have the same punch as the “darkness and winter throughout the whole world for decades” nuclear winter message.

  38. 88

    Re: #48 by Susanne on defining world temperature and determining change. An informative source on this subject is:

    Scroll down to Frequently Asked Questions. My general understanding is that thermometers around the world on land and on sea buoys and from ships gather temperature data. The land temps are measured from about 1 to 2 meters above the surface, and sea temps are taken from about the same distance above the surface,and sea surface temps are taken from ships. Corrections are made for things such as height of the ship above the water surface, and urban heat island effect(which turns out to be negligible). The data are combined and carefully statistically analyzed to arrive to arrive at a global temperature.

    Changes in temperature are compared to a base such as the average Earth temperature say between 1961-1990, and the deviation from that base are used to determine changes.

  39. 89
    Neil B. says:

    You folks will want to get out responses to the following AGW-skeptic jerimiad, about satellite data saying earth’s temperature has gone down since 1998 etc:
    This is good also for readers, so I can see what good answer to give.

  40. 90
    Jim Galasyn says:

    2007 Is Warmest Year Yet for Hemisphere

    The Northern Hemisphere is the warmest this year since record-keeping started 127 years ago, according to the National Climatic Data Center.

    Temperatures for January through October averaged 1.3 degrees above the norm. If the trend continues, the year could break the record for the warmest set in 2005.

    The Southern Hemisphere is its ninth-warmest since record-keeping began, the center said. Worldwide, this is the third-warmest year through October.

    The USA has also seen warmer temperatures recently: The period from January to October was the seventh-warmest since records began in 1895, according to the national data center. The warmest for that period was in 2000; the second-warmest was in 1934.

    The only month cooler than average was February, while seven months were described as “much above average.” Temperatures in March and August were the second-warmest recorded for those months. …

  41. 91
    Ron Taylor says:

    Re #42

    It is physics, Cody, really very basic physics. I am a retired engineer and it is astounding to me that someone who claims to be a paleo-climatologist would not understand that. Or that someone who claims to be a paleo-climatologist would not recognize the unprecedented rate of CO2 and temperature increase. Who are you, really? What are your academic qualifications for the professionalism you claim? What have you published in the peer-reviewed literature?

  42. 92
    Charles Muller says:

    #90 I suppose it’s an example of alarmism. At the beginning of the year, and following a Hadley Center prediction, many medias announced 2007 would be the warmest year on records. Ten months later, the Hadley Center CRU database show that it’s not the case and that there”s no more global anomaly in 2007 than in the previous six years. And RSS as UAH agree for low troposphere (Nasa Giss is a bit more warm than 1998 when you compute with a 1200km interpolation, but a bit less with a 200 km interpolation)

    Et hop ! In order to maintain an alarming buzz, the new alarming claim is restricted to NH – because of course, GHGs are not well-mixed, warming is not global, feedbacks don’t operate on SH, etc.

    Hadley record (txt) :

    UAH record (txt) :

    RSS record (txt) :

  43. 93
    J.C.H. says:

    Andrew (#8) – The basic argument against Greenland being lubricated by moulins and sliding off into the ocean is that the weight of the ice has created a topographic bowl whose center is below sea level. If Greenland’s ice were perfectly free to slide, most of it would stay where it was. …” John N-G

    To me it’s a structure. A very tall and heavy one that is getting taller and heavier year by year. No architect designed it. Structural engineers did not select the materials and think through all the stresses. I don’t know that I would presume all of the ice will remain perched on top of its below-sea-level basement to have it simply melt in place in a linear forever when it’s aggressively rotting rotting away each summer at its lower level. For some reason I do not believe it’s an ice cube in a spoon.

    Wings usually stay on airplanes. When they break off, there’s a reason. Something failed. Tall buildings are not supposed to fall down when there is a fire. How much taller than the WTC is the Greenland ice sheet?

    If the aggressive erosion of ice at the base continues, what prevents huge hunks of it from toppling or sliding down to near sea level where it would melt much faster than they would have at its former elevations?

  44. 94
    Don Condliffe says:

    The IPCC concensus like most of the scientific literature is far too cautious and very much the lowest common denominator. The very rapid disappearance of the Greenland ice sheets in the past, which is documented in the scientific literature, is best explained as the result of positive feedback loops and we should expect rapid sea level rise at an increasnig number of meters per century starting now. The scientific concensus is still stuck on gradualism rather than open to seeing what is in the geologic record, namely repeated catastrophes. Sticking with the herd, climate scientists keep shutting off the fire alarm so as not to cause panic when actually alarm is the appropriate response.

  45. 95
    Hank Roberts says:

    Jim Galasyn writes: “… many medias announced …”
    This is why it helps if you provide a source for what you think you remember. You’re remembering headlines, but not the actual story.
    You can look this stuff up. Here’s a news story.

    They blew the link title:

    Someone got it right in the Headline:
    Is 2007 Going to Be The Warmest Year Ever Recorded?

    The writer or editor got it wrong and right in different paragraphs:
    “There is a probability of 60% that the average surface temperature will overpass the current record established in 1998.”

    Conclusion? They guessed wrong on El Nino (we are in a La Nina) and stated a probability slightly over 50:50, and the story writers blew it badly. You got fooled.

    Yep, you can find overblown claims in news stories. This is why actually reading the science and citing what you base your beliefs on avoids confusing and misleading people, or even yourself.

    Human memory is fallible and our wishes often are the hobbyhorses we ride.

    Try citing your sources. It’s good for you and everyone reading.

  46. 96
    Harold Ford says:

    I did enjoy the movie “The Day After Tomorrow” so this book doesn’t sound quite alarmist to me lol (but I still should read it…). Mark, did you go over hauling dirt up to the North and South poles to enable the continuation of growing food? Alarmist, ha. Thinking and speculating rationally sounds more likely. Or, maybe, shining a flashlight in the dark to see the cockroaches scurry for cover?

  47. 97
    Chris C says:

    Cody Griffin may be an expert, but he doesn’t appear to up-to-date on what is going on. I found one post by him (based on the same logical fallacies presented above). Back to Lynas….

  48. 98
    Edward Greisch says:

    56 Barton Paul Levenson: You are wrong. Thank you 85 Jim Dukelow. The Chernobyl accident put out as much radiation as a coal fired plant of the same capacity does in 7 years and 5 months. A standard 1000 megawatt coal fired power plant puts an average of 4 tons of uranium into the air and cinders every year. That 4 tons of uranium is enough to fuel a nuclear plant for the same year. If breeding thorium into uranium is allowed and plutonium is allowed as a fuel, you can get a huge amount of nuclear fuel from coal smoke and cinders. Chernobyl was obsolete when it was built. It can’t happen here. Coal is almost pure carbon, except for the URANIUM, ARSENIC, LEAD, MERCURY, Antimony, Cobalt, Nickel, Copper, Selenium, Barium, Fluorine, Silver, Beryllium, Iron, Sulfur, Boron, Titanium, Cadmium, Magnesium, Calcium, Manganese, Vanadium, Chlorine, Aluminum, Chromium, Molybdenum and Zinc that are coal’s impurities. Using coal cinders as a source of these minerals would be commercially viable. Even though transportation uses more energy, coal fired power plants put more CO2 into the air. See:

    58 Walt Bennett: There is no reason to reduce productivity. In fact, not having to mine and ship 4 MILLION TONS of coal for every 1000 Megawatt coal burning power plant would free up a lot of capacity. The nuclear plants that replace them need so little U235 per year that you could carry the same weight as the annual supply in a suitcase. Each 4 MILLION TONS of coal becomes 14.7 MILLION TONS of CO2. If nuclear power safety were reduced to a reasonable level, nuclear power would cut the price of electricity a lot. Coal is the dangerous one. We have made enormous strides in nuclear safety in the last 60 years. We have 2 types of reactors that cannot melt down due to the laws of physics. We can, if allowed, use nuclear waste as fuel.

    68 Aaron Lewis: For your 100 year timeframe, read “The Long Summer, How Climate Changed Civilization” by Brian Fagan, 2004 Basic Books, ISBN 0-465-02281-2
    Summary: Smaller climate changes than we have caused already, caused the fall of many civilizations. It is unlikely that civilization will last 100 more years if we don’t mend our coal burning ways.
    In your 200 year timeframe, the paleontologists are telling us that we will go extinct if we don’t mend our CO2 output. Here are some URLs to copy and paste:

  49. 99

    Ron Taylor (#91) wrote:

    Re #42 [Cody Griffin]

    It is physics, Cody, really very basic physics. I am a retired engineer and it is astounding to me that someone who claims to be a paleo-climatologist would not understand that. Or that someone who claims to be a paleo-climatologist would not recognize the unprecedented rate of CO2 and temperature increase. Who are you, really? What are your academic qualifications for the professionalism you claim? What have you published in the peer-reviewed literature?

    I found oddly similar arguments being made quite recently by a “Cody Griffin” in Oklahoma who calls himself a professional geologist.

    Please see:

    Ludicrous at best
    Cody Griffin
    professional geologist
    Published: November 18, 2007 12:14 am

    Stillwater is in Oklahoma.


    There also seems to be a fellow who called himself ” ‘Cody’ Griffin” who was a retired petroleum geologist that worked for Mobile, but he died in 2005. But I am assuming this isn’t the same person.

    Please see:

    November 2005 Obituaries Orleans Parish Louisiana
    Submitted by N.O.V.A. (New Orleans Volunteer Association) December 2005

    And there is another Cody Griffin, young-looking lad, perhaps in his early thirties, living in Midland, Texas. Congratulations are in order for that fellow. Looks like he found himself a beautiful wife. (I am omitting the link.)


    Finally, there is something called Griffin Petroleum Company located in Midland, Texas, no doubt owned by a family with oil in their blood.

    But all of this is probably just one large coincidence. I doubt it has anything to do with our paleoclimatologist here.

  50. 100
    Lawrence Coleman says:

    I humours me is that so called paleoclimatologists who should be educated people still cant seem to see the wood for the trees. Re: 42 Cody Griffin. The world hundreds of millions of years ago was a very volatile place, much incresed volcanic activily, tectonic activity and if the story books were half accurate, much greener and more humid. That was probably the era when the famous arizona meteorite hit. It is foolish to base present conditions on what occured at that time. The sun has been relatively stable for at least the past million years, the incidence of volcanos and probably earthquakes has settled down as the earth reaches middle age. There are no sudden catastrophic events that have affected the earth for the last mil years at least apart from a few ice ages that were triggered by small fluctuations in surface temp. The difference this time is one of extent quite apart for the absolute commen sense logic of pumping out billions of tonnes of carbon and other greenhouse chemicals into the air is going to affect our climate. Carl Sagan used to say that if the world was the size of the globe that you had on your desk the biosphere would be no thicker than it’s single coat of varnish. What that should tell anyone with half a that quarter of a brain is that the atmosphere is very fragile and delicate indeed. It doesn’t take much abuse to get it out of kilter. We have been abusing it since the industrial revolution at an exponentially growing rate…I am gobsmacked and astonished the climate has been so resilient to date, but what is painfully clear now is that there is overwhelming evidence that it is finally breaking down.