364 Responses to “Uluslararası Iklim Değişikliği Görevgücü’nün 4. Değerlendirme Raporunun Politika Belirliyicileri Icin Özeti”

1. cbone Says:
   2 February 2007 at 11:08 AM

   Where may I obtain a copy of the actual report, instead of just a summary?

   [Response: The full report won’t be finalized until April. –eric]

2. catman306 Says:
   2 February 2007 at 11:25 AM

   Just mentioning another possible environmental disaster linked to global warming and climate change: when the Greenland glaciers finally melt (either slowly or in a big whoosh) tectonic rebound will probably increase the frequency and magnitude of earthquakes around the world. The 30 foot rise in sea level will cause the Antarctic ice shelves to detach making it easier for the Antarctic glaciers to move more quickly into the ocean, causing still more sea level rise, tectonic rebound and earthquakes.

   Nice world we are leaving our grand children. And theirs.

   [Response: I am happy to be able to correct you that tectonic rebound from the Greenland ice sheet won’t have impacts on earthquakes around the world. Big earthquakes are due to processes much deeper in the earth’s crust, and much more localized. It is, on the other hand, rather likely that rising sea levels will help to destabilize the Antarctic ice sheet. On what timescale, however, remains quite uncertain. –eric]

3. BCC Says:
   2 February 2007 at 11:27 AM

   Minor, minor observation:

   even we need time to digest it

   I know it wasn’t the intention, but that comes across as a little arrogant. I know that you are professional climatologists and wicked smart and all, but I would have gone with sometihing like “and we need time to digest it too.”

   Minor point, but tone matters.

   [Response: Fair enough! Of course what was really meant is that virtually all of the science being reported on is stuff that we are already very familiar with. “Digesting it” means making sure that what we think is in it (even before reading it) is actually in the final text, we most of us, like you, have just gotten a chance to start reading. -eric]

4. Mitch Golden Says:
   2 February 2007 at 11:29 AM

   The direct link to the summary report (that is, what was published today) is here:

   http://www.ipcc.ch/SPM2feb07.pdf

   Keep an eye on http://www.ipcc.ch/ to see the other sections as they’re released.

5. P. Lewis Says:
   2 February 2007 at 11:32 AM

   The immediate thing that stood out for me about the AR4 SPM is the willingness to talk (again) about “the globally averaged net effect of human activities since 1750″, whereas here and hereabouts, of recent times, there has been more of a “let’s keep it to the last ~50 years” kind of discussion (whether by accident or design).

   I find this encouraging, for the science.

6. curving3 Says:
   2 February 2007 at 11:37 AM

   You can find the SPM report at: http://ipcc-wg1.ucar.edu/

7. Anonymous Says:
   2 February 2007 at 11:59 AM

   “Scientists offered Cash to Dispute Climate Study”

   http://www.commondreams.org/headlines07/0202-05.htm

8. Dave Cohen Says:
   2 February 2007 at 12:00 PM

   Note that some media have been comparing apples with pears here: they claimed IPCC has reduced its upper sea level limit from 88 to 59 cm, but the former number from the TAR did include this ice dynamics uncertainty, while the latter from the AR4 does not, precisely because this issue is now considered more uncertain and possibly more serious than before

   This is very confusing to the public. The 59 cm is the upper bound in the A1F1 scenario. I quote from AR4 –

   Models used to date do not include uncertainties in climate-carbon cycle feedback nor do they include the full effects of changes in ice sheet flow, because a basis in published literature is lacking. The projections include a contribution due to increased ice flow from Greenland and Antarctica at the rates observed for 1993-2003, but these flow rates could increase or decrease in the future. For example, if this contribution were to grow linearly with global average temperature change, the upper ranges of sea level rise for SRES scenarios shown in Table SPM-2 would increase by 0.1 m to 0.2 m. Larger values cannot be excluded, but understanding of these effects is too limited to assess their likelihood or provide a best estimate or an upper bound for sea level rise.

   Who among us expects a decreasing or linearly growing flow rate from the ice sheets until the year 2100? This would make recent trends anomalous. The public will see a lower number and not understand that the trend is “more serious than before” — and also not understand recent not-included studies that indicate accelerating flow rates in Greenland and W. Antarctica. Already there is considerable confusion in the media. This constitutes a disservice to mankind.

9. Sean Davis Says:
   2 February 2007 at 12:07 PM

   #1, the report can be found here

10. Zeke Hausfather Says:
    2 February 2007 at 12:09 PM

    Sorry to nitpick, but it would be nice if, when finalizing a report that is to be read by hundreds of millions of people, the authors could remove unfinished formating suggestions (e.g. [Numbers to be converted to mm per year] on page 5 and [To be changed: Change annotation from cnstant composition to year 2000 constant concentration. Colour central bar in grey bars and lettering to match A2, A1B, B1 curves as appropriate. Drop model numbers and move to caption] on page 21). It makes an otherwise well-crafted report appear unprofessional. Both of the copies report linked from the IPCC site have these formatting errors, at least at the time of posting:
    http://ipcc-wg1.ucar.edu/wg1/docs/WG1AR4_SPM_PlenaryApproved.pdf
    http://www.ipcc.ch/SPM2feb07.pdf

11. Sean Davis Says:
    2 February 2007 at 12:11 PM

    I think I already found an error in the SPM! If you sum up the contributions to sea level rise from 1993-2003 in table SPM-O, you get 0.657, not 0.28. I think they screwed up the Greenland and Antarctic values, which they list as 0.21 (each). If you assume they are 0.021 instead, the sum total contribution is indeed 0.28.

    OOPS!

    [Response: Well spotted. I noticed this as well and alerted IPCC a few hours ago. -stefan]

12. CobblyWorlds Says:
    2 February 2007 at 12:12 PM

    BBC News24 are announcing it as the end of “the debate” about the reality of climate change.

    So that means the real battle to get individuals to factor this into behaviour is now starting. It seems to me that our only attainable option is to aim to take the edge off the increases by energy efficiency etc. Drop the talk about “Stop Climate Chaos”, implications that we can just stop fall in the face of evidence and reason. Argue for the attainable; piecemeal reduction of emissions. Do what you can. Every little helps.

    But I think it would have been a stronger “coup de grace” had it been presented at the same time as the WG1 Scientific Basis report. Surely as it’s based on the results of WG1 they could have finalised the full Scientific Basis first?

    BCC.
    These are the sort of people who do stuff as cheeky as attempting to model something as complex as climate and pull it off! (e.g. http://rabett.blogspot.com/2006/09/well-lookee-that.html ) As an intellectual also-ran I request RealClimate leaves the ‘even’ in.

13. Karan Says:
    2 February 2007 at 12:13 PM

    Neal Boortz attempted to criticize the report. Very interesting and ALL flawed. What’s worse is that he uses it to convince listeners, who have no knowledge of the science and believe him. http://boortz.com/nuze/index.html

14. E. C. De Fabo Says:
    2 February 2007 at 12:44 PM

    It would be both very good and very useful to have a point by point rebuttal of the charges this fellow makes. Not being a climatologist’s but certainly someone with a great deal of interest in this subject (I am a research scientist in photobiology) who gets called on to comment occasionally on global climate change (stratospheric ozone depletion/UVB impacts) it would help to have some good strong arguments to counter the comments by this person. Good references would be most appreciative as well.

15. Spencer Weart Says:
    2 February 2007 at 12:48 PM

    A few errors I’ve noted in the media coverage.

    1. Most reports I’ve heard say that the IPCC says it’s 90% likely that etc. Actually their term “very likely” means 90-99% certain.

    2. Most reports talk about temperature rise etc. by 2100. Actually the summary gives the averages expected 2090-2099, a half-decade sooner. Not significant I suppose but annoying.

    3. Most reports I’ve heard mention a 1.5-4 degree C expected rise. These are actually the best estimated central values for different economic-technological scenarios. Fair enough, but the ranges of temperatures the IPCC considers “likely” go from 1.1-2.9 for the most benign emission scenario to 2.4-6.4 for the least benign one (that’s the one with the 4.0 “best estimate”), so the actual “likely-depending-on-what-we-do” range is 1.1-6.4

    [Response: Spencer, your second point is quite relevant for sea level, where leaving off the last 5.5 years (when it rises fastest) and other technicalities are the reason why the new sea level values look a bit lower than the previous model projections. In fact, all else being equal, for any given emission scenario the new (AR4) models give a slightly higher sea level projection than the old models used in the TAR, we were told in Paris. -stefan]

16. Jake Says:
    2 February 2007 at 12:53 PM

    O.K., so if we assume there is a human coponent, how do we know what percentage of global warming is attributable to humans and, even if we were to stop any further increase from the human component, that would slow down or even reverse the process?

17. Jake Says:
    2 February 2007 at 1:19 PM

    Also, Spencer: let’s say “very likely” means 99% certain that (human) greenhouse gases have caused most of the observed increase in globally averaged temperatures since the mid-20th century. What does “most” mean in regard to my pending questions? Does that include gases from non-human sources? Keep in mind that the Paris study, looking at all the science of global warming, will only project a “best estimate” that temperatures will rise by 3 Celsius (5.4 Fahrenheit) by 2100 over pre-industrial levels. I doubt that is bad enough for the entire world to stop in its tracks.

18. lars Says:
    2 February 2007 at 1:31 PM

    #16 exactly…… if humans are the culprit…..

    Should you not be calling for reducing the human population on this planet then?

    Should you not be doing a Kyoto on China, India, and Muslims which each have approximately 1.3 billion and growing populations?

19. Steven Leibo Ph.D. Says:
    2 February 2007 at 1:35 PM

    Just want to think RealClimate for its efforts to help non-scientists to understand the new report. I am part of Al Gore’s Climate Project and working very hard to improve my understanding of all this to complement the local presentations of his slide show I am doing. Realclimate makes that much easier!

20. Sashka Says:
    2 February 2007 at 1:38 PM

    The SPM predicts 20% drop in precip in subtropics. Do we trust the models enough to beleive the projections for regional shifts in precip?

21. Scott L. Montgomery Says:
    2 February 2007 at 1:41 PM

    Release of this new IPCC summary is a profound event and will be covered by every major newspaper in the world, as it should. Scientifically speaking, no other domain benefits from such a magnificent collaboration of investigators, whose task is to summarize the published literature into concise, universally usable reports - imagine if every field of science had the benefit of such review! What a boon to researchers and the public both. But climate-related science especially demands this level of attention - it is a political decision to do this, not merely an intellectual one, for it reflects the importance and urgency of the relevant information, not to mention the widespread lack of action that it suggests is needed.

    To my mind, as a sometime student and scholar of scientific expression past and present, the report is a well-tuned document. It’s authors have clearly learned a thing or two from the last go-around. It is crisp, data-rich, fairly well-organized, and confident in its points. It uses qualitative but explained probabilities (extremely likely, very likely, likely, etc.), discusses (in yellow-highlighted boxes) the significance of the knowledge domain covered by each section, and admits uncertainties. It is not a policy document, per se: it does not recommend or critique specific measures, ideological concepts, weigh risks and benefits, or the like. It has what might be termed a low intimidation factor, meaning that nearly all the scientific points are comprehensible to the educated layperson. There is a pictorial rhetoric, too, that is very effective. The graphics, though placed at the end instead of embedded in the narrative (as in most scientific documents) are improved from the TAR (2001 report). Going through them has a cumulative effect that even supersedes that of the text. Especially interesting and well-done, in visual terms, is the global map showing temperature trends since 1900 for the major continents. The final two pages of figures, a culmination of sorts, showing predicted temperatures and precipitation patterns for the remainder of the century, are visually striking, and thus daunting. There is calculated force here (on the eye and mind), to be sure, but one that is warranted by the results. To claim this as “propaganda” would be absurd and naive: all effective documents employ these sorts of persuasive tools, and have done so since manuals of rhetoric were written in Greek and Roman times (Galileo’s famous little book, Sidereus nuncius, with the first pictures of a rocky moon, is a superb example).

    But here’s another point. It is not just the content of this document that matters with regard to its place in our evolving discussion on climate change, but how it’s represented in the media. This may be obvious, but the reality is a complex affair. Compare, for example, this morning’s coverage by the International Herald Tribune and our favored NYTimes. The former discusses the importance of the report, it’s confirming aspects with regard to the phenomenon of global warming, and implications, with some spicing of comments by authors and reviewers, some rather silly ones (”This is real. This is real. This is real.”) Most important, though, the article emphasizes that the science is not complete but in progress, and that the new report represents a further step in this process. Yes, we all know this, but saying it in these terms is fairly rare in newspaper and tv reports. As for the NYTimes, they decided to beat the drum of controversy: “Even before its release, world climate report is criticized as too optimistic.” It is focused almost entirely on the discussion over predicted sea level rise - the decision of the IPCC not to include potential ice melt, which is largely (as I understand it) due to timing issues of the published material and also uncertainties related to modeling. Moreover, the article ends with a little melody from Fred Singer about the IPCC being the contrarians now. This is indeed poor stuff from our most valued daily paper, but not really surprising.

    The media are able to bring a critical faculty to bear on scientific subjects, but choose to do so on a haphazard and selective basis. Highlighting controversy, or manufacturing it, is not merely a way to attract attention; it is also a means of distinguishing your own reporting from that of other papers. The most basic aspect to climate science - that it is science-in-the-making, always advancing, always partial, always ready to jettison some things and improve others, and therefore any summary of it will be no more than a snapshot of what has already been surpassed - does not make for good news all the time. Reporters serve different masters than scientists, not necessarily kinder and gentler ones. The final truth is that the media are not necessarily well-qualified, on their own, to transmit technical knowledge to the public, but they are what we have. To understand these matters better, I’d recommend reading Dot Neklin’s book “Selling Science,” which remains the more clear-eyed treatment of the subject.

    In the meantime, we will have to grit our teeth, hope, and sometimes smile at the popular treatment of this new, epochal report. Given the momentum that is now building in the U.S., I expect that good things will come out of the IPCC’s work. As I say, we can certainly hope so.

22. Mike Says:
    2 February 2007 at 1:44 PM

    Jake at #16:

    If you look at the SPM, page 16, there is a nice table of the magnitudes of various factors, anthropogenic and natural. The anthropogenic factors total out to a forcing of 1.6 Watts/m^2, while the natural factors are 0.12. Clearly, the human factors are the biggie. The vast majority of the current warming is ‘our fault.’

    There was also discussion of the ‘% attribution’ question here at RealClimate back in October: http://www.realclimate.org/index.php/archives/2006/10/attribution-of-20th-century-climate-change-to-cosub2sub/

    As for how much we have to change our behaviors before we restore our climate to a pre-industrial state, I think it can’t happen. A certain amount of warming is going to be with us for centuries. What we have to do is stop accelerating the process, so that the total warming is smaller than what are are currently heading towards.

23. Sashka Says:
    2 February 2007 at 1:50 PM

    Scientists and economists have been offered $10,000 each by a lobby group funded by one of the world’s largest oil companies to undermine a major climate change report due to be published today.
    Letters sent by the American Enterprise Institute (AEI), an ExxonMobil-funded thinktank with close links to the Bush administration, offered the payments for articles that emphasise the shortcomings of a report from the UN’s Intergovernmental Panel on Climate Change (IPCC).

    http://www.guardian.co.uk/frontpage/story/0,,2004399,00.html

24. Hank Roberts Says:
    2 February 2007 at 1:55 PM

    Jake, see the name immediately above your question? click on it to read: http://www.aip.org/history/climate/

25. juandos Says:
    2 February 2007 at 2:08 PM

    The comment taken from the leftist rag the Guardian, “Scientists and economists have been offered $10,000 each by a lobby group funded by one of the world’s largest oil companies to undermine a major climate change report due to be published today”…

    Hmmm, so what did the IPCC pay people who for the most part aren’t scientists to come up with this myth called global warming?

    [Response: Indeed an intellectually brilliant conspiracy theory… But in case anyone seriously wants to know: the 600+ scientists working on the IPCC reports do this for free in their spare time. That involves lots of hours wading through review comments (the report attracted over 30,000 such comments), and evenings and weekends away from the family. A voluntary effort I right now don’t feel like ever doing again, once seems enough for a lifetime… -stefan]

26. tom street Says:
    2 February 2007 at 2:08 PM

    I would like to see more discussion of the reasons for the increase in probability regarding man induced climate change and how one goes from a 60 percent probability to a ninety plus probability. It’s not like rolling dice, I presume, so how precise are these probability estimates. Are they similar to the kinds of probabilities we get from noaa when we look up the forecasted weather? Or what?

    The primary reason I bring this up is the fact that Lindzen seemed to make fun of the whole notion of probability the other night on CNN. Yes, I can understand that all this data and analysis makes us more certain, but is it really reasonable to put a number on it?

27. Pat Neuman Says:
    2 February 2007 at 2:10 PM

    Re: 2

    Could tectonic rebound from ice loss on Greenland and Antarctic result in additional significant increases in sea level?

    For example, if something raised a portion of the bottom area of a lake, the displacement of the water would increase the surface level of the lake (assuming no lake outlets).

28. Jason Burford Says:
    2 February 2007 at 2:16 PM

    Does anyone know of any literature summarizing positive feedback effects. In particular I am interested in boreal permafrost feedbacks such as thawing permafrost, burning boreal forests…do these feedbacks overtake man made emissions scales and were these considered in the report findings such as shrinking sea ice was (hopefully)?

29. Jeremy Kenyon Says:
    2 February 2007 at 2:24 PM

    First, I totally agree with point 8 - why did they put in a 59cm upper bound that nobody seems to think is likely to be right - it is confusing, misleading and will be seized on by contrarians. At the very least they should have included an apples to apples comparison, as well as the one discounting the effect, especially in the summary, which is all that many folks will ever read.

    Second - Point 13, Neal Boortz discussion - even if he was right, which is unlikely, he still seems to be saying that global warming is happening. Also he says that the IPCC are saying it is futile as we can’t stop it. That does seem to be the impression I get as well.

    It seems to me that we need to start taking the whole issue of what to do about it a lot more seriously - emissions control is not going to be enough, even if it was incredibly aggressive, and the more optimistic models are right.

    We are most likely going to have a sea level rise over the next century that will cause problems, and the rise will continue in the century after that, and possibly for quite a bit longer.

    Either we need to really give up on places like Bangladesh and Venice and Northern Africa and so on, or we need to get some serious research going into putting the genie back in the bottle.

    I know this is not a popular sentiment amongst climate scientists right now but I really don’t see that we have a choice, do we? Either we accept widescale disruption in the next 100-300 years with phenomenal human cost, or get cracking on finding additional techniques as well as the current ‘reduce carbon emissions’.

    Any additional techniques, such as widescale stratospheric aerosols, or iron filings in the ocean or such like are going to take a decade or more to research, do tests with etc. During that time, the accuracy of models will continue to improve, as will our understanding of ice melt behaviour and the other uncertainties.

    My current project is investigating the current set of options we have for attempting to reduce the impact of global warming - there are about a dozen methods at the moment, varying from plausible to blue sky. We need to push research for this sort of work way up the agenda, instead of it being the poor cousin to analysing what is actually happening - they go together - understand how it works and then changing things to improve the situation.

    Please note - I completely believe the current approach of reducing carbon emissions is necessary, so that we can return to a relatively stable climate and avoid having an even bigger problem to face in the future. But while that happens, I think we have to have additional measures in place, or face a huge human cost.

    Contrarians talk about how we will eventually go into the next ice age, as the climate changes no matter what we do. That is very likely true, and when that starts to happen, we are also going to have to deal with it, or accept even more destructive changes to the planet (I don’t want to get into the philosophy here of that issue…). That is not a reason to ignore the current problems. We have built a world that depends on a very stable climate, and until the population drops dramatically or we can easily adjust, we are going to have to try to maintain that stability, against the current warming and a future cooling.

30. Mattias Dahlstrom Says:
    2 February 2007 at 2:24 PM

    A question regarding sea water rise…
    If seawater would rise … say 10 m … would the seafloor compact a bit, resulting in less than 10 m effetive rise?

31. David B. Benson Says:
    2 February 2007 at 2:26 PM

    Pat Neuman — Tectonic rebound takes many thousands of years. The rebounding area you suggest is but a tiny fraction of the surface area of the oceans.

32. Chip Knappenberger Says:
    2 February 2007 at 2:34 PM

    A few comments:

    RC writes:

    How good have previous IPCC reports been at projecting the future? Actually, over the last 16 years (since the first report in 1990), they’ve been remarkably good for CO2 changes, temperature changes but actually underpredicted sea level changes.

    The AR4 states:

    Since IPCC’s first report in 1990, assessed projections have suggested global averaged temperature increases between about 0.15 and 0.3ºC per decade for 1990 to 2005. The can now be compared with observed values of about 0.2ºC per decade, strengthening confidence in near-term projections.

    Indeed, the observed trend in global temperatures is about 0.2ºC per decade from 1990 to 2006 (or 2006 for that matter). What seems to be forgotten both by the IPCC and Rahmsdorf et al. (or at least swept far under the rug in Rahmsdorf et al.), is that a big volcano went off in 1992 and cooled global temperatures for 2-3 years afterwards (if not a bit longer). A big non-anthropogenic cooling near the beginning of the period of record being compared in one dataset (the observed data) and not in the other (the collection of IPCC model results) doesn’t lend itself to an appropriate comparison. Using a longer period of record, say 1977-2006, shows the observed global warming to be about 0.17ºC per decade, or, alternatively, removing the known volcano-influenced years, say 1992 and 1993, from the 1990-2005 period of record produces a warming rate of about 0.15ºC per decade. Take your pick. But, in either case, the observed warming rate is certainly in the low range of IPCC projections (from any IPCC report) for the period 1990-2005.

    Also, RC comments about sea level rise and the potential contribution from ice sheet dynamics, quoting the IPCC AR4 SPM:

    Dynamical processes related to ice flow not included in current models but suggested by recent observations could increase the vulnerability of the ice sheets to warming, increasing future sea level rise. Understanding of these processes is limited and there is no consensus on their magnitude.

    I would like to add that also found in the IPCC AR4 SPM is the following concerning the role of dynamic ice processes on sea level rise:

    Models used to date do not include uncertainties in climate-carbon cycle feedback nor do they include the full effects of changes in ice sheet flow, because a basis in published literature is lacking. The projections include a contribution due to increased ice flow from Greenland and Antarctica at the rates observed for 1993-2003, but these flow rates could increase or decrease in the future. For example, if this contribution were to grow linearly with global average temperature change, the upper ranges of sea level rise for SRES scenarios shown in Table SPM-2 would increase by 0.1 m to 0.2 m. Larger values cannot be excluded, but understanding of these effects is too limited to assess their likelihood or provide a best estimate or an upper bound for sea level rise.

    Notice the phrase “but these flow rates could increase or decrease in the future” [emphasis mine]. While some commentors may choose to ignore this (e.g. RealClimate) and others may think that it is a “disservice to mankind” (e.g. comment #8), nevertheless, the IPCC authors felt that the current state of the science necessitated its inclusion.

    -Chip Knappenberger
    to some degree, funded by the fossil fuels industry since 1992

    [Response: First, my name is Rahmstorf. Second, I find your accusation that we sweep something under the rug bizarre, since we show all the data since 1973. I invite everyone to see for themselves; to those without subscription, our paper can be accessed through the link on my home page. -stefan]

33. Andrew Sipocz Says:
    2 February 2007 at 2:39 PM

    Re: #28. Something else would sink as Greenland rose but the timing would vary and contribute to the natural sloshing around of global sea level. I post this because I’m amazed at our need to totally understand how the earth and everything works. Somewhere, sometime, some comedian needs to do a skit of how we torture ourselves over our need to know every little detail. It kills my wife. Much more to worry about right now, but as an example the U.S.’s Gulf of Mexico coastline is slowly sinking in response to the melting and subsequent rise of the lands once under the laurentide ice sheet (see Gonzales and Tornqvist in Eos, Vol. 87, No. 45, 7 November 2006).

34. SecularAnimist Says:
    2 February 2007 at 2:57 PM

    Would the moderators consider deleting the ignorant, sneering, hostile, insulting, content-free and completely worthless remarks from the flame troll identifying himself as “juandos”? Such drivel belongs on Free Republic or some other right-wing hangout, not here.

35. Jim Redden Says:
    2 February 2007 at 3:06 PM

    Re 21 [SPM and the media]

    As Scott writes: The media are able to bring a critical faculty to bear on scientific subjects, but choose to do so on a haphazard and selective basis.

    Indeed. Several media venues have a different spin.

    Popular media behavior is shaped by market forces; hence, the need for a hooking headline and topic based on culling and maintaining readership. Akin to what you have said, I submit media choices are the best guess of an editor seeking to satisfy readership, advertisers, and stockholders.

    Meanwhile, I am going to keep my eyes out for the reaction of ecologists–who can try to make sense of what will happen in the oceans–as currents accommodate to new exchanges of energy, and the poles continue to warm so much faster than the rest of the globe.

    Frankly, my guess is one may very well be able to start watching the collapse of ocean food chains on the news eventuallyâ��partly due to pollution, and overexploitationâ��and now overtaxed by new ocean transport current relationships which are sure to emerge–perhaps without specific prediction. While the task of the IPCC does not stipulate exploring the reaction of ecosystems, the crux of our most vexing of problems will be how the Earth as a whole reacts on a granular level to the new phase composite of climate. Sea level rise may rank as the simplest tasks to deal with.

    So far, rather predictably, the reaction to the report seems to resolve around preconceived attitude and how one tends to lens the world. As others have implied in an earlier thread, pure unadulterated science transcends rhetoric. Move to science applied, and politics rears a head. (The Boortz fellows web site left me shaking my head.)

    As an aside, reading the many earlier threads as of late, on real climate, has been quite time consuming�yet worthwhile. To see such discourse, with some well founded scientific explanation and outlinks�I am thankful.

36. Pat Neuman Says:
    2 February 2007 at 3:08 PM

    Thanks for your comment. I wanted reassurance, with the thaws happening much quicker now vs the thaws in Earth’s history and those which didn’t involve Greenland and Antarctica. I’ve seen photos of the mud flats near near Anchorage, apparently from rebound. I was surprised by the magnitude of the lifting in that area. Maybe there’s more at work near Anchorage than rebound - like the giant quake they had in the 1960s.

37. LochDhu Says:
    2 February 2007 at 3:31 PM

    Typo police:

    Actually, over the last 16 years (since the first report in 1990), they’ve been remarkably good for CO2 changes, temperature changes but actually undepredicted sea level changes.

    I assume you meant to type underpredicted. Keep up the good work!

    [Response:Thanks! - gavin]

38. Mark Zimmerman Says:
    2 February 2007 at 3:39 PM

    Does the IPCC address the recent paper by Lyman et al., documenting ocean cooling the past couple years? Or has this work been dated already by more recent data?

39. garhane Says:
    2 February 2007 at 3:39 PM

    I do not know if anyone will ever work out the evidence, but this lay reader is assured the contributors of Real Science have been a strong support for the work of hundreds of scientists who have worked to make the report of or to the IPCC the best science can do. This is due to the steadfast centering function RC has performed. Unhappily it will now be needful to prepare for the attacks of a crowd of ideologues who are even worse than the gang that could not count, the economists. I guess someone will come forward, but they will have quite a job to measure up to the standard RC has set. Three cheers and a tiger.

40. James Stample Says:
    2 February 2007 at 3:55 PM

    Climate change. Maybe man made maybe not! But what does it matter. We obviously will have to make some tough decisions!
    Let me pose a Question?
    Lets say there is a large asteroid discovered on a collision course with earth!
    At that time, we may have many ways of which to stop this catastrophe. But maybe just maybe this is our only oppotunity to reverse the global warming issue by allowing it to strike! Therebye starting a new iceage.
    Are we ready to assume all resposibility for mankind who seems to be more concerned about whats causing global warming then the ultimate effects of sustained ignorance will lead us.

    Some day we will have to decide!
    It may mean that we lose half of the earths population but mankind will endure.Or will we?

41. Ark Says:
    2 February 2007 at 4:08 PM

    #11: data for Greenland and Antarctica are messed up for the 1961-2003 period as well (factor of 10 too high). I guess those data were in mm/year instead of m/century (cf. the editing note above the table that they forgot to remove). Probably American authors, for them mm are units from Mars, like Btu/ft2/h for us Europeans.

42. Lynn Vincentnathan Says:
    2 February 2007 at 4:25 PM

    RE #12, yes, every little bit helps. So print these 21 pages on used paper, if possible, or doubled-sided on recycled paper. I get my used paper at the university library, mainly page separator sheets, and it’s high grade. First REDUCE, second REUSE, third RECYCLE.

    I forgot what the cut-off date was for the journal articles included in AR4. Was it June 2005 or 2006?

    I always take these reports as being on the conservative side of conservative, since they require great consensus, beyond the typical conservative (false-positive avoiding) single scientific studies. I think the cutting edge studies of dangerous predictions would indicate greater harms than what IPCC indicates (though the reports do include ranges, but may excluded the highest ends).

    Another point, each succeeding report not only reveals greater precision in the science, but also that global warming is more potentially dangerous than experts had earlier thought. I might be wrong, but that’s the sense I get.

43. Sean Davis Says:
    2 February 2007 at 4:40 PM

    Ark, You’re right. They apparently screwed up the Antarctic contribution for 1961-2003 as well in Table SPM-0. Also, if you assume they meant 0.014, the numbers in the 1961-2003 column don’t add up (i.e. .042+.05+.05+.014 = .156, NOT .11 as they have in the table)

44. Barton Paul Levenson Says:
    2 February 2007 at 4:44 PM

    [[Now that you are one of those who are either ignorant beyond all help or just a pathological liar, do you have any other excuses for being a fear monger?

    Just asking… ]]

    Stay off the sauce when you post. It improves the quality of your prose.

45. Robert Ellison Says:
    2 February 2007 at 4:45 PM

    Where is the discussion of natural variability in all this? There is of course the minor contribution of solar irradiance but the changes over the ENSO cycle, over decadal timescales and over longer period don’t rate a mention. The decadal variance in particular is dismissed at Wikapedia as climate noise and addressed on this site as a single paragraph and a blind link. How is this possible?

    The cyclical changes in global temperature and climate more generally over periods of decades - to 1946, 1947 to 1975 and 1975 to 1998 in the instrument record - and, from proxy data, occuring 11 times in the past 400 years with an average duration of 23 years.

    FAR predicts a 0.2 degree C/decade rise in temperature over the next couple of decades. The history of decadal variability suggests that temperatures will decline (since 1998) over the next couple of decades - well before which the entire science community is utterly discredited. Don’t believe me - this is very simple experiment and one that doesn’t require 5000 of the world’s leading scientists.

    Random fluctuation is not much of an explanation for such a persistent and influential phenomenon. I feel like being very rude but will of course refrain. Feel free to claim that the temperature decline since 1998 is random climate noise - pretty much as the CRU did on New Years Day 2007 when claiming, after 2006 came in at the sixth warmest year, that 2007 will surely see the upward trend return. I am not likely to be listening until I see the data.

46. Ajit Singh Says:
    2 February 2007 at 4:45 PM

    Says RK Pachauri, DG, The Energy and Resources Institute & Chair IPCC: “A number of scientists say Siachen should be made a protected area, a heritage site of sorts, and that there should be no army presence on either side. For purely ecological reasons, this *might* be a good idea. But I *don’t* see why there would be melting as a result of military presence and activity.” The *s show a vagueness unworthy of an environment leader who ought to ask for withdrawal of all troops immediately’
    Please Cleck to see how indian and Pakistan Army melting Siachen glacier
    www.zeenews.com/articles.asp?rep=2&aid=345084&ssid=26&sid=ENV - 58k -
    www.wwfpak.org/15-01-07meltingofthesiachenglacier.php - 32k - Cached - Similar pages
    in.news.yahoo.com/061230/211/6apcs.html - 39k - Cached - Similar pages
    www.thenews.com.pk/daily_detail.asp?id=38553 - 21k - Cached - Similar pages

47. Hans Vermeer Says:
    2 February 2007 at 4:46 PM

    While you can appreciate the representation of scientific knowledge, available late 2006, in this IPCC report, you might wonder how it will affect the political decision-chain. Here in the Netherlands, the rather conservative estimates on sea-level-rise already led to (secondline) features in the national television news show, in which the one-line statement “Holland will not be flooded…” sounded like a sense of relief. But even without accounting for possible dynamic changes in icecaps the consequences stated in the report make clear there is not much relief while reading carefully. My point is that it is not just a question of how much sea-level-rise will occur. Agricultural and land-use change, growing salinity of groundwater and estuaries, re-arranging drinking-water facilities, changing character of rivers etcetera. This will put an ever growing strain on our national budget. Not to mention the help we might want to offer in less fortunate regions in the coming world. It is time to be clever and to accept that it might cost us a considerable amount of our “business as usual” to cope. I just hope the full fourth assessment will contribute to that awareness!

48. Lee Morrison Says:
    2 February 2007 at 4:55 PM

    Any significance to the fact that the report was released on Grounfhog Day? “If the groundhog sees his shadow, there’ll be another six weeks of winter.” (Probably as valid as some of the exquisitately accurate computer modelling with questionable input data.)

49. David B. Benson Says:
    2 February 2007 at 5:00 PM

    Sea stand rise — On another thread, Nigel Williams asked for a 500 year prediction. I offered 7 m for the melting of the Greenland ice sheet and up to 20 m (conservatively high) for the melting of the West Antarctic ice sheet. So minor adjustments due to isostacy and tectonic rebound are just too insignificant to consider when faced with a long-range prediction of 22–27 m.

50. David Price Says:
    2 February 2007 at 5:06 PM

    One query concerns precipitation. In a warmer world the oceans will warm, causing more evaporation. The warmer air will be able to hold more water. Therfore one would expect a greenhouse world to be a lot wetter. Yet the report forecasts droughts and reductions in rainfall most places.
    This is odd, especially in the tropics where there will be a lot of extra precpitation looking for somewhere to go. Where will it all end up?

51. Lynn Vincentnathan Says:
    2 February 2007 at 5:09 PM

    #15, thanks, Spencer, for that clarification. I had thought that 1.5-4 degree C range must have been the climate sensitivity range for 2X CO2, because 4 degrees didn’t seem like the worse-case human emissions scenario (at highest sensitivity). And I believe TAR had the upper figure (of worse case scenario) at 5.8 degrees C. So the AR4 figure would be an increase — am I right? But the media have been jumping around these past few months saying AR4 indicates GW will not be so bad, bec they’ve ratcheted down the warming figures.

    #16, Jake, I’m also concerned with natural GHG emissions increasing due to the warming that the human emissions have caused. I do hope AR4 deals with that, even though such positive feedbacks entail a lot of uncertainty.

    So my question then would be, is 6.4 degrees C the upper end only for the worst case of human emissions (at the highest sensitivity), and thus leaves out the positive feedbacks (nature emitting due to the warming, lower albedo from melting ice)? I mean, is there a possibility of even a higher temp when both human emissions and positive feedbacks are considered.

    From what I understand, positive feedbacks (e.g., from melting permafrost & clathrates, & reduced albedo) are not included in the models.

    #17, I do think a 3 degree increase would be pretty disasterous, esp for the poor peoples of the world (& it would make the rich a lot poorer); it’s sort of like the reichter scale - the change from a 6 to a 7 involves a lot more danger & harm than from a 5 to a 6, so a rise from 2 to 3 degrees C with GW would probably entail a lot more harms than a 1 to 2 degree increase, with a 5 to 6 degree increase extremely bad. You don’t want to go there. I’m just waiting to get Mark Lynas’s SIX DEGREES when it comes out in March; in lay language he takes us through each degree increase — 1, 2, 3, 4, 5, 6 degrees — and what each degree increase would mean re effects and harms.

52. Oldfart Says:
    2 February 2007 at 5:19 PM

    Just today the opposition (CNSNews.com) is claiming that language such as “One final point is that improvements in the clarity of the language from the SPM should be propagated back to the individual chapters in order to remove any superficial ambiguity. The science content will not change.” is simple proof that making the science fit the summary is what is being done. The idea that a negotiated political “summary” should propagate it’s language back to the detailed science is very suspicious to many people for whom global warming as a result of human activity is NOT a clear fact.

53. Ark Says:
    2 February 2007 at 5:20 PM

    #43: Sean, I’m pretty sure that it’s mm/year in both Greenland and Antarctic ice sheets numbers 1961-2003 (like in 1993-2003 numbers). So in metres/century: 0.042+0.050+0.005+0.014=0.111, or approx 0.11.

54. Karan Says:
    2 February 2007 at 5:31 PM

    This is extremely shameless. Steven Milloy at www.junkscience.com has released the draft of the working group 1. How desperate will these political puppets get?

55. Ells Says:
    2 February 2007 at 5:49 PM

    Re #15: Maybe just a typo but the SPM defines “very likely” as 90% to 95% certain, “Extremely likely” covers 95% to 99% certain. Very glad to to see the precise definitions of terms that still carry an effective qualitative message.

56. Hans Erren Says:
    2 February 2007 at 5:49 PM

    re 19:

    Will Al Gore adapt his sea level projection for The Netherlands?
    http://www.ukweatherworld.co.uk/forum/forums/thread-view.asp?tid=5609&start=1

57. pete best Says:
    2 February 2007 at 5:53 PM

    I personally believe that the biggest issue related appears to be the rate of CO2 increase and hence the time that it takes for 2 C of warming to take place. Currently annual emissions increases are 2 ppmv but recent years have seen 2.6 and 2.5 ppmv increases, if that accelerates to 3 ppmv somehow then we could be out of time as 100 ppmv increase to 480 ppmv which would take 50 years at 2 ppmv will only take 33 years at 3ppmv.

    i wonder what the latest 2006 annual increase rates are and whether this is set to increase?

58. Sean Davis Says:
    2 February 2007 at 5:56 PM

    I just put up a new post summarizing what (I noticed) has changed in the IPCC from TAR to AR4.
    IPCC SPM- So What’s New?

    Cheers,
    Sean

59. Walt Bennett Says:
    2 February 2007 at 6:01 PM

    (If my comment is not suitable for posting, please email me and explain why, thank you.)

    I had asked in the previous blog post (comment was not posted):

    Do we have some sort of numerical representation for the greenhouse effect? In other words, a measurement of total solar energy which reaches the surface, and what percent is direct sunlight versus what percent is the greenhouse effect. Do we have such a number, and have we tracked changes in it (and for how long?

    Thank you.

60. SecularAnimist Says:
    2 February 2007 at 6:08 PM

    Off topic, but …

    The American Solar Energy Society today released a 200 page report, “Tackling Climate Change in the US: Potential U.S. Carbon Emissions Reductions from Renewable Energy and Energy Efficiency by 2030″ which outlines how the USA can reduce its carbon emissions by 60 to 80 percent by 2030 with improvements in efficiency and deployment of existing clean, renewable energy technologies.

    The 60 to 80 percent reduction is in line with what is needed to keep CO2 concentrations below 450 to 500 ppm, which is what most scientists believe is necessary to prevent the worst effects of global warming.

    Fifty-seven percent of the carbon reductions are from energy efficiency improvements, and forty-three percent are from renewables. No expansion of nuclear power is included in the proposal.

    I know that many frequent contributors to these comment pages are very interested in solutions to the problem of reducing US carbon emissions, and will find this report useful.

61. Ajit Singh Says:
    2 February 2007 at 6:14 PM

    Dr Rajendra Pachauri, IPCC chairman and DG, The Energy and Resources Institute & Chair IPCC: “A number of scientists say Siachen should be made a protected area, a heritage site of sorts, and that there should be no army presence on either side. For purely ecological reasons, this *might* be a good idea. But I *don’t* see why there would be melting as a result of military presence and activity.” The *s show a vagueness unworthy of an environment leader who ought to ask for withdrawal of all troops immediately! Click to see the view of chairman IPCC
    http://www.dnaindia.com/report.asp?NewsID=1076589
    So, we should not expect a lot from IPCC, currently head by Dr Rajendra Pachauri, as his biased, unprofessional remarked already appeared in news paper and enough to say that it would be another media hype and noting else.

62. SecularAnimist Says:
    2 February 2007 at 6:17 PM

    Walt Bennett wrote: “Do we have some sort of numerical representation for the greenhouse effect? In other words, a measurement of total solar energy which reaches the surface, and what percent is direct sunlight versus what percent is the greenhouse effect. Do we have such a number, and have we tracked changes in it (and for how long?”

    Yes, NOAA tracks that, and reports on it every year in the Annual Greenhouse Gas Index, using 1990 as the baseline.

    NOAA’s May 2006 report, for 2005, found that the total “greenhouse effect” had increased by 21 percent since 1990.

63. Stuart Staniford Says:
    2 February 2007 at 6:28 PM

    In the SPM-0 table, in the 1993-2003 column, not only do the central values not add up, but the errors don’t compute either. If the Antarctic uncertainty was 0.35m/century, that would dominate the uncertainty in the sum which would therefore have to be much larger than 0.07m/century.

    Pretty surprising to see elementary errors like this in such a profoundly important document. Too many late nights? It’s still broken as of right now.

    [Response: It’s a simple unit conversion error, some values (including their error bars) are accidentally in mm/yr, not in m/century, hence they are a factor of 10 too large. -stefan]

64. SecularAnimist Says:
    2 February 2007 at 6:30 PM

    More evidence of global warming:

    PUNXSUTAWNEY, Pennsylvania (AP) — A new pair of hands pulled Punxsutawney Phil from his stump this year, so it was only fitting that the groundhog offered a new prediction.

    Phil did not see his shadow on Friday, which, according to German folklore, means folks can expect an early spring instead of six more weeks of winter.

65. Marcus Says:
    2 February 2007 at 6:41 PM

    #52: Walt: Figure SPM-2 in the new summary shows the (direct) anthropogenic contribution to the greenhouse effect of 1.6 W/m2 (0.6 to 2.4 W/m2 bounds). One presumes there would be a further indirect effect of increased water vapor forcing and albedo change from melting ice that aren’t quantified here (though they do quantify albedo change from black carbon in snow and land use).

    This compares to: average sunlight: about 240 W/m2 (that’s 1368 W/m2 divided by 4 for surface area of a sphere vs. a circle times 0.7 for earth’s albedo) (said insolation keeps us at 255 K), plus natural greenhouse of about 150 W/m2 (bringing us to 288 K). With about 0.1 W/m2 solar increase since 1750.

    They don’t report the increased forcing from the 6 SRES scenarios, but I would guess (looking at temperature changes) that the direct forcing increases range from 3.5 W/m2 to maybe 12 W/m2 above preindustrial.

    So perhaps 8 W/m2 direct anthropogenic forcing, with additional forcing from water vapor/cloud and ice albedo changes of perhaps 3 times the direct effect (a rough estimate based on a climate sensitivity of 3), means 32 W/m2 human caused forcing, which would be equal to an increase of 20% in natural forcing or a 13% increase in the Sun, or an 8% increase in all forcing. That’s pretty big (enough for 6 degrees C above preindustrial at equilibrium). Obviously, changes in climate sensitivity estimates or emissions forecast can increase or decrease that number by a lot.

    (RC moderators, please correct me if I’ve made any calculation errors)

66. Dan Says:
    2 February 2007 at 6:41 PM

    re:53. “How desperate will these political puppets get?”

    Money talks a lot for the likes of them.

67. Pat Neuman Says:
    2 February 2007 at 6:48 PM

    Re 49 … a lot of extra precpitation looking for somewhere to go. Where will it all end up?

    A lot of the extra precipitation will end up falling as rain in the higher latitude regions.

    The increase in humidity will increase latent heat.

    The significance of latent heat for snowmelt has been described by Dunne and Leopold (1978):

    �If water from moist air condenses on a snowpack, 590 calories of heat are released by each gram of condensate. This is enough energy to melt approximately 7.5 gm of ice, which when added to the condensate yields a total of 8.5 gm of potential runoff�.

    http://www.mnforsustain.org/climate_snowmelt_dewpoints_minnesota_neuman.htm

68. SolarNTrains Says:
    2 February 2007 at 7:00 PM

    Re: 59 - Excellent URL with good, pragmatic information. IMHO I don’t think it is realistic to assume 60 to 80% alt energy is achievable without nuclear. While I can’t speak for the other sources, I know from work experience that solar has major challenges, and even the authors of the article don’t describe potential outcomes as “likely”. But any amount would be an excellent start.

    BTW, secularanimist, go lite on us conservatives(ala 34 and other comments on RC) that don’t always agree with you.

69. RepublicanGuy Says:
    2 February 2007 at 7:34 PM

    “The major natural greenhouse gases are water vapor, which causes about 36-70% of the greenhouse effect on Earth (not including clouds); carbon dioxide, which causes 9-26%; methane, which causes 4-9%, and ozone, which causes 3-7%. It is not possible to state that a certain gas causes a certain percentage of the greenhouse effect, because the influences of the various gases are not additive.” Greenhouse Gas via Wikipedia.

    Well what is it for CO2? 9% or 26%? That looks to me a pretty big margin of error. A multitude of 3 margin of error, ouch.

    http://en.wikipedia.org/wiki/Greenhouse_gas

    ______________________________

    99 ppm added CO2 from pre-industrial to 2007.

    So how much more thermal energy is added to earth per square kilometer, with 99 more ppm, and how much would that theoretically raise the temperature of the earth in total? Theoretically speaking. No need to adjust for clouds, water vapor, etc, just how much more thermal energy is added.

    http://www.ipcc.ch/SPM2feb07.pdf

    [Response: Funny guy. You should probably investigate where that information came from - I’m sure it’s reputable and they’ll probably explain what the range means…. (hint) - gavin]

70. Marcus Says:
    2 February 2007 at 7:49 PM

    RepublicanGuy: 9% to 26% is not _margin of error_ it is a fundamental difficulty in assigning a number. The number you get by taking a vacuum and adding 270 ppm of CO2 is a lot different than the number you get by taking the preindustrial atmosphere and subtracting 270 ppm CO2 (I would guess that 26% is the first approach and 9 % the second). This occurs because the various gases have overlapping spectra.

    The SPM states that the increase in CO2 leads to a 1.66 W/m2 increase in forcing. I know that doubled CO2 (4 W/m2) has about a 0.8 degree C direct contribution to temperature (along with .7 to 3.7 degrees feedback), so 1.66 W/2 would be about 0.3 degree C, with 0.3 to 1.4 degree additional feedback expected. We’ve seen 0.8 degrees of warming, and expect 0.6 degrees more, which falls within that range.

    Does that answer your question?

71. Joseph Siry Says:
    2 February 2007 at 8:12 PM

    The current scientific consensus is (found in comparing AR-4 to TAR) based on far greater certainty that global warming is due to human actions, that the sharp rise in heat trapping gases since the 1950s is not a natural cycle, and this condition will not soon go away. The evidence is clear that actions must be taken soon because the rates at which carbon dioxide, methane and nitric oxide are increasing are unprecedented. Present levels of carbon dioxide in the atmosphere have not been detected on earth for over 600,000 years.

    Because of these facts, ocean chemistry and temperature are undergoing an accelerating change. Levels of rainfall are increasing in the polar latitudes. Heavy precipitation events occur more frequently and rapid runoff of rainwater increases the rate of erosion. In the sub-tropics there is less rainfall predicted. Given such trends, our inability to manage water, protect low-lying coastal areas and reduce the loss of topsoil should promote widespread caution.

    These facts make it clear that actions needed to cap and then reduce the rate of heat trapping gas emissions will have greater impact if taken sooner, than if we stall in efforts to be more energy efficient. Because warmer oceans and land areas will persist for decades, if not centuries, institutional changes must be encouraged now to assist the most vulnerable and curb inherent inefficiencies in power consumption and transportation.

    As the U.K. government campaign is fond of saying tomorrow’s climate depends on today’s actions.

72. Dave Says:
    2 February 2007 at 9:25 PM

    Does anyone have any insight as to how Richard Lindzen developed views that are so far out of the scientific mainstream? Is he just kissing the hand that feeds him or are his views of climate change part of a monetary (Grover Norquist-like) or religious (rapture - obsessed) conservative ideology?

    [Response: Somebody else can figure out the psychology of Lindzen’s denialism, but it’s not really important. What’s important is whether he has any arguments that bear scrutiny. The last actual argument he published was the IRIS cloud feedback mechanism, a good many years back, which did not stand up to scrutiny. All of his earlier arguments (cumulus drying, super-lapse-rate feedback) were demonstrably wrong. So far as I can tell he has stopped making scientific arguments. That’s what counts. He’s playing his MIT professorship for all that it’s worth, but that’s all he’s got going for him right now. –raypierre]

73. Roger Smith Says:
    2 February 2007 at 9:52 PM

    I think Lindzen’s always been a maverick and because of that has asked questions about what others just assumed to be true. This approach may be wrong 99% of the time, but it’s the 1% that wins scientific awards. Hopefully he’ll stop wallowing in the 99% soon and move on.

74. Dave Cohen Says:
    2 February 2007 at 9:59 PM

    I’ve got to ask — what is the deal? I posted (#8), and my colleague (#64, and others) posted on how the AR4 math is wrong, showing that global sea level rise is not well accounted for in the publicly released document.

    I am forced to ask — considering some “Freudian Slip” situation — how the release of this long-awaited 2007 document could both 1) do the math wrong and 2) discount current sea-level rise trends from the big ice sheets in Greenland and W. Antarctica.

    I eagerly await some reponse — or “rationalization” — as to how this can be explained.

75. Lee Morrison Says:
    2 February 2007 at 10:15 PM

    #71 Sorry that you disliked my post sufficiently to zap it, Dan. I’m retired, but I was a successful and (I think) respected scientist for almost 40 years. I do know a little bit about what constitutes science. Computers have made our work immeasurably easier, but they haven’t yet replaced the ability of human beings to think logically and collect data objectively. Clever computer programming is a valuable skill, but it isn’t science.

76. Scott L. Montgomery Says:
    2 February 2007 at 10:18 PM

    #61. Thanks very much for the link to this report! It does indeed talk about renewables and energy efficiency, as carbon mitigation measures for the U.S. and proposes we can reduce carbon emissions by 60-80 percent this way. Unfortunately, the report is a theoretical treatise–its authors were asked what they thought could be potentially accomplished, given resource assessments and technological capabilities. No consideration is given to many real world aspects, such as the politics of land use and ownership, full costs of deployment and existing power plant replacement, grid adjustments, ecological problems (due to the very large land requirements for large scale solar and wind), and much much more. These sorts of pie in the sky studies have plagued renewables from the beginning and torture us with the prospect of revolutionary change, but they do a disservice to an industry that is now in the throws of real practical expansion, due to both high energy prices and climate change worries. But these forces have their limits, as do renewables themselves. As presently conceived, renewable sources will not run the world, or even a large portion of it. They are currently less than 1 percent of global energy use, and though very important for a range of countries, from Iceland to India, they are far from equal to the task of turning over the 12 trillion dollar fossil fuel system. The future lies with energy diversity, an expanding and increasingly flexible portfolio of sources. Technology won’t solve it all, by any means, but it will help enormously. For a good discussion of energy issues related to climate change, see John Holdrens article The Energy Innovation Imperative, at http://bcsia.ksg.harvard.edu/BCSIA_content/documents/Innovations_The_Imperative_6_06.pdf
    The future lies with a diversity of sources

77. Robin Henkys Says:
    2 February 2007 at 10:38 PM

    Doing some late night reading on this subject as a result of the vast media coverage of the IPCC report. I personally haven’t really had any doubts about the human impact on global warming, but I am merely a student of Computing and have no deep scientific understanding of the subject (one tries though).
    This is just a thank you to the authors for this blog.

78. Stormy Says:
    2 February 2007 at 10:41 PM

    To the editors:

    According to The Guardian, the AEI (American Enterprise Institute) thinktank is offering $10,000 to anyone who will cast doubt on the report, scientists and economists included.

    I suggest you get a copy of that letter and publish it here, together with who funds the AEI.

79. wayne davidson Says:
    2 February 2007 at 10:44 PM

    #37 Pat, Rebound has been continuous process since the last ice age, quite severe in the Arctic, where you find very old Bow head whale skeletons, ancient half burried walruss skeletal heads 160 meters above sea level! Present rate around where I live is about 2 cm a year, where raised beach ridges are a common shoreline sight..
    What recent GW does to rebound is a very good question…

80. Andrew Dessler Says:
    2 February 2007 at 10:51 PM

    I blogged on the new IPCC report and my take here. Take a look and let me know what you think.

    [Response: Hi, Andrew. I think this is a very nice summary of the highlights of the report. I’ll leave it to Mike Mann to comment on your take on whether the nuances of the NAS statement on climate of the past millennium is significantly different from what the SPM says. It all comes down to details of how one estimates the uncertainty in reconstructions of medieval warmth. Nobody can say that the Medieval was definitely warmer (hemispherically) than the present, but some might say that the error bars are large enough that one cannot rule out the possibility. In some sense you are right that there were no real scientific breakthroughs reported in this round. The improvements were incremental, and the big news was in how fast the Earth’s climate is changing. The SAR, in contrast, introduced a breakthrough in the aerosol connection to interrupted warming, whereas the TAR had some breakthroughs in coupled ocean-atmosphere modelling. The timing of AR4 just missed the next big breakthrough — which will be in improved and coupled modelling of glacier dynamics, including fracture mechanics, ice shelves and all that stuff. I think one mustn’t discount a breakthrough of a technological sort in AR4 though: The number of model runs exploring more of scenario and parameter space is vastly increased, and more importantly, it is available in a coherent archive to the full research community for the first time. The amount of good science that will be done with this archive in the next several years is likely to have a significant impact on our understanding of climate. –raypierre]

    [Response: One clarification on the point made by Ray P above. Actually, the IPCC statement is stronger than what Ray suggests. The careful choice of wording by the IPCC on this indicates that they did think we can rule out the possibility that Medieval large-scale warmth was comparable to the present at a moderately (likely=67%) high level of confidence, and that is of course taking into account the fact that there are uncertainties. –mike]

    [Response: As we note in the piece above, the NRC did endorse the key conclusions of IPCC (2001) with regard to millennial reconstructions, hence news reports in e.g. Nature such as “Academy Affirms Hockey-Stick Graph”. Nonetheless, the NRC report was a rush job, was forced to ignore key papers in the pipeline, and had limited representation of experts in paleoclimatology (perhaps seeking breadth but sacrificing depth in this key area in their selection of panel members). By contrast, the IPCC was a long, careful, deliberate process, based on several years of thorough assessment of the literature, the IPCC paleoclimate chapter was written by leading experts in the field of paleoclimatology, and input was solicited from essentially every leading expert in the field. It should be unsurprising that they came to a somewhat different (and in my view, more accurate) bottom line. I hope that answers the question for you Andrew? –mike]

81. Colorado Bob Says:
    2 February 2007 at 11:22 PM

    Neal Boortz is on the attack :
    25 Reasons to blah, blah, blah ……

    http://boortz.com/nuze/index.html

82. Peter Says:
    2 February 2007 at 11:53 PM

    What are your thoughts regarding Christopher Monckton’s analysis of the 4AR?

    http://ff.org/centers/csspp/pdf/20070201_monckton.pdf

83. Alvia Gaskill Says:
    3 February 2007 at 12:16 AM

    Bodman et al. Embrace IPCC Report Sort Of

    After the IPCC Committee delivered its report, officials from the U.S. government gave their take on it. Energy Secretary Sam Bodman, NOAA Administrator Conrad Lautenbacher and EPA Administrator Stephen Johnson each made remarks and answered questions. (shown on CSPAN2).

    They said that they and the Bush Administration embraced the IPCC report and that without the funding for scientific research sought for and received by the president starting in 2002, the IPCC would not have been able to deliver its final product. In other words, U.S. government funded research was responsible for much of the scientific content in the report.

    Bodman cited 7 DOE supercomputers funded by the Bush administration as key elements in generating this scientific work.

    All three repeatedly referred to the $29 billion spent by the Bush administration over the last 6 years on climate change research and greenhouse gas mitigation.

    So where did this figure of $29 billion originate? Only a few years ago the White House was claiming that it spent $2 billion a year on climate research and then $3 billion and now the $29 billion figure so frequently quoted by administration spokesmen today.

    That would work out to about $5 billion per year and indeed seems be consistent with the numbers in a WH press release from last year. See below.

    From 2001 To The End Of 2006, The Federal Government Will Have Devoted Over $29 Billion To Climate Programs, More Than Any Other Nation. The President�s 2007 Budget proposes $6.5 billion for climate change activities.
    http://www.whitehouse.gov/news/releases/2006/07/20060711-7.html

    However, others, including the National Environmental Trust, the GAO and AAAS haven’t had much success in verifying these numbers.

    http://www.net.org/proactive/newsroom/release.vtml?id=29017

    http://www.net.org/proactive/newsroom/release.vtml?id=29048

    http://www.aaas.org/spp/rd/cctp06p.pdf

    Some people, like James Hansen, for example, have openly complained about budget cuts in monitoring programs. What then is the true story of the $29 billion? The link below to the USAID provides a breakdown by agency and area.

    http://www.usaid.gov/our_work/environment/docs/fy07_climate_change.pdf

    The money spent in 2006 was about as follows:

    Climate Science $1.9 billion of which $1.3 was from NASA.

    Climate Change Technology Program $2.8 billion of which $2.5 was from DOE

    Tax Credits $1 billion

    The proposed increase in 2007 is mostly due to a big increase in the tax credits, while the science funding drops off.

    EPA and NOAA’s funding are less than $200 million each, although Lautenbacher and Johnson did not seem concerned about this.

    Of the DOE’s budget, around $1.2 billion is in the category Energy Efficiency and Renewable Energy. Somewhere between $500 million and $1 billion is associated with carbon capture and sequestration.

    The biggest complaint about these numbers is that the Bush administration has continually broadened the definition of what constitutes climate change research and mitigation, thus making it appear that the funding for this area is skyrocketing when in fact it is actually going down in some categories.

    Bodman also said that the U.S. would not adopt a GHG cap unilaterally, out of concern this would drive jobs overseas to countries with no caps and lax air pollution standards, thereby making the overall problem worse.

    A reporter then pointed out that Germany has had caps in place for several years and has experienced job growth. Bodman said he was sure someone would perform an economic analysis that would clarify this.

    Another reporter asked that since California now has its own version of a GHG cap in place, wouldn’t it be expected to lose jobs? Bodman said he thought this would be the outcome.

    One hopeful note. Bodman said that U.S. scientists would be made available to talk to the media about the IPCC report. Of course, he didn’t say which scientists and under what circumstances. After all, buried somewhere in the $29 billion is a line item titled Salaries.

84. BarbieDoll Moment Says:
    3 February 2007 at 12:54 AM

    (Re: 2

    Could tectonic rebound from ice loss on Greenland and Antarctic result in additional significant increases in sea level? )

    However there are not the observed temperature changes in the Antartic, so isn’t that
    putting the cart before the horse? ….

    “Climate Change 2007: The Physical Science Basis Summary for Policymakers
    Working Group I”
    IPCC WGI Fourth Assessment Report, (Feb 2007)
    http://www.ipcc.ch/SPM2feb07.pdf report

    …..”Some aspects of climate have not been observed to change. {3.2, 3.8, 4.4, 5.3}

    “â?¢ Antarctic sea ice extent continues to show inter-annual variability and localized changes but no statistically
    significant average trends, consistent with the lack of warming reflected in atmospheric temperatures
    averaged across the region. {3.2, 4.4} “….

    …”It is likely that there has been significant anthropogenic warming over the past 50 years averaged over each continent except Antarctica (see Figure SPM-4).”….

    …”â?¢ Global average sea level in the last interglacial period (about 125,000 years ago) was likely 4 to 6 m higher than during the 20th century, mainly due to the retreat of polar ice. Ice core data indicate that average polar temperatures at that time were 3 to 5°C higher than present, because of differences in the Earthâ??s orbit. The Greenland ice sheet and other Arctic ice fields likely contributed no more than 4 m of the observed sea level
    rise. There may also have been a contribution from Antarctica. {6.4}”…

    …”Current global model studies project that the Antarctic ice sheet will remain too cold for widespread surface melting and is expected to gain in mass due to increased snowfall. However, net loss of ice mass could occur if dynamical ice discharge dominates the ice sheet mass balance. {10.7}”…

    and one could refer to any of the following as well for other science on the matter

    ECORD: IODP Expedition 310-Tahiti Sea Level
    http://www.ecord.org/exp/tahiti/310.html

    “So far, the only sea-level record that encompasses the whole deglaciation is based on offshore drilling of Barbados coral reefs which overlie an active subduction zone and was located close to the former ice sheets during the Last Deglaciation. Vertical tectonic movements in such areas may be large and are often discontinuous, implying that apparent sea level records may be biased by variations in the rates of uplift. Hence, there is a clear need to study sea level changes in tectonically stable regions or in areas where vertical movements are slow and/or regular. Furthermore, the eustatic function is best estimated from sea level data collected far from the former ice margins where the the influence of glacio-isostatic rebound is minimized”…

    Volcanic and tectonic processes coinciding with glaciation and crustal rebound: an early Holocene rhyolitic eruption in the Dyngjufjöll volcanic centre and the formation of the Askja caldera, north Iceland
    Bulletin of Volcanology 64 (3-4), 192 (2002)
    http://dx.doi.org/10.1007/s00445-002-0204-7

    “A pronounced volcanic production maximum on the rift zones through Iceland coincided with rapid crustal rebound during and after glacier melting at the Pleistocene/Holocene boundary. At peak glaciation, ice thickness over central Iceland may have reached 1,500-2,000 m, causing 400-500-m depression of the crust. Rapid climatic improvement caused glacier melting and removal of the ice load within about 1,000 years. Low mantle viscosity resulted in rapid crustal rebound which was completed in about 1,000 years, with an average rate of uplift on the order of nearly half a metre per year over central Iceland.”..”A model is proposed involving uplift of tectonically well-defined crustal blocks to the north and west of the Askja caldera, combined with downsagging caused by voluminous outpouring of basaltic lava. The southern and eastern borders of the caldera are remnants of a subsidence following the 10-ka Plinian eruption, partly reactivated by the 1875 A.D. Plinian eruption. The model provides a satisfactory explanation for the enigmatic Ã?skjuop pass, and it is in agreement with a gravity survey of the Dyngjufjöll centre. The uplift coincided with rapid crustal rebound which was amplified by crustal deformation (doming) of the volcanic centre caused by high magmatic pressure in the plumbing system of the volcano. This is supported by emission of very large lava flows produced in the first millennia of the Holocene. ”

    Decontaminating tide gauge records for the influence of glacial isostatic adjustment: The potential impact of 3-D Earth structure
    Geophysical Research Letters 33 (24), 24318 (30 Dec 2006)
    doi:10.1029/2006gl028448
    http://dx.doi.org/10.1029/2006gl028448

    Observation of glacial isostatic adjustment in â??stableâ?? North America with GPS
    G F Sella et al.
    Geophys. Res. Lett 34 (L02306), (26 Jan 2007)
    http://dx.doi.org/10.1029/2006gl027081
    _____________________________________________

    RE: (51. …”Yet the report forecasts droughts and reductions in rainfall most places.”)

    “Climate Change 2007: The Physical Science Basis Summary for Policymakers
    Working Group I”
    IPCC WGI Fourth Assessment Report, (Feb 2007)
    http://www.ipcc.ch/SPM2feb07.pdf

    ..”â?¢ The frequency of heavy precipitation events has increased over most land areas, consistent with warming
    and observed increases of atmospheric water vapour. {3.8, 3.9}”…

    _______________________________________________
    RE: (46. Where is the discussion of natural variability in all this?”)

    “Climate Change 2007: The Physical Science Basis Summary for Policymakers
    Working Group I”
    IPCC WGI Fourth Assessment Report, (Feb 2007)
    http://www.ipcc.ch/SPM2feb07.pdf

    ….”â?¢ Difficulties remain in reliably simulating and attributing observed temperature changes at smaller scales.
    On these scales, natural climate variability is relatively larger making it harder to distinguish changes
    expected due to external forcings. Uncertainties in local forcings and feedbacks also make it difficult to
    estimate the contribution of greenhouse gas increases to observed small-scale temperature changes. {8.3,
    9.4}”….

    and the footnote

    “1 Climate change in IPCC usage refers to any change in climate over time, whether due to natural variability or as a result of human activity. This usage differs
    from that in the Framework Convention on Climate Change, where climate change refers to a change of climate that is attributed directly or indirectly to human
    activity that alters the composition of the global atmosphere and that is in addition to natural climate variability observed over comparable time periods.”

85. naught101 Says:
    3 February 2007 at 12:55 AM

    why to the IPCC use the “Virtually certain”, “Extremely likely”, “Very likely”, “Likely”, “More likely than not”, “Unlikely”, “Very unlikely” and “Extremely unlikely” qualifiers? it makes it difficult to read. it would make much more sense to just use a range of likelyhoods - “it is 90-99% likely that x will happen.” much easier to read, and also less restrictive, as figures such as 85-95% could be used, or specific figures with uncertainties: 90% ±4%. this would make the entire report that little bit more accurate, and MUCH, MUCH easier to read.

    the same could go for the “High Confidence” etc.

    #26: absolutely classic. I haven’t heard a comment so backwards for years! I’m gonna have fun with comments like these in the next few weeks.

86. Mike Hart Says:
    3 February 2007 at 2:44 AM

    A quick question for the RC crew or any other scientist re Polar cap changes. ‘Are there any studies about the possibility of a orbital shift for the planet with the change in mass from ice to water?”. I note a recent private published book by Prof Lance Endersby who suggests that such orbital shifts may have been induced by glacial change in the past. A suddent orbital shift would be more than catastrophic it would suggest a major extinction event. Any responses would be appreciated

87. BarbieDoll Moment Says:
    3 February 2007 at 2:45 AM

    I gather that this prelim policy laymen’s type of summary report is not the actual technical bling-bling we should expect of the IPCC AR4 coupled climate models, because according to LLNL, such will be released in chapter 8?

    As far as a sense of homogeneity across the models, what actual number of modeling input factors (ex: Co2, solar, clouds) would encompass the said physical sciences of “atmosphere, land surface, ocean and sea ice” that were submitted specifically to the IPCC AR4 for consideration? Ten ? More, less?

    Additionally, will the release of chapter eight further quantify the uncertainties, bias, differences and so forth in relation to the various model versions simulations, within their range and scope, in consideration to their ability to reproduce, replicate, and or be in some form of a consensus data output agreement?

    Or will we have diverging model outputs that persist in diverging projected climatic opinions or lack of certaintities? Excusing of course the nonlinearity factors of the natural climate systems which will always, I assume, interject its whims; especially at the shorter intervals versus longer climate patterns; further compounding the matter for modelers.

    About IPCC Model Output
    http://www-pcmdi.llnl.gov/ipcc/about_ipcc.php
    …”the PCMDI is archiving coupled ocean-atmosphere general circulation model output to support the Working Group 1 component of the IPCC’s 4th Assessment Report. The data archived by the PCMDI from each participating coupled ocean-atmosphere model is a subset of that model’s output. Working Group 1 of the IPCC focuses on the physical climate system — atmosphere, land surface, ocean and sea ice — “…

    Important Information for Analysts and Authors
    http://www-pcmdi.llnl.gov/ipcc/info_for_analysts.php
    ..” The overall purpose of Chapter 8 of the AR4 is to assess the ability of the global climate models to make projections of future climate change.”…

    IPCC Climate Model Documentation, References, and Links
    http://www-pcmdi.llnl.gov/ipcc/model_documentation/ipcc_model_documentation.php

88. BarbieDoll Moment Says:
    3 February 2007 at 3:48 AM

    (RE:2 ..”Greenland glaciers finally melt (either slowly or in a big whoosh) tectonic rebound will probably increase the frequency and magnitude of earthquakes around the world.”…)

    If the thought intrigues you, there are research papers out there
    discussing the topic and or similar trains of thoughts.

    RETREATING GLACIERS SPUR ALASKAN EARTHQUAKES
    http://www.nasa.gov/centers/goddard/news/topstory/2004/0715glacierquakes.html (08/02/200)

    “In a new study, NASA and United States Geological Survey
    (USGS) scientists found that retreating glaciers in southern
    Alaska may be opening the way for future earthquakes.”…”Even though shrinking glaciers make it easier for earthquakes
    to occur, the forcing together of tectonic plates is the main
    reason behind major earthquakes.”…

    “Earthquakes in Greenland: Are They Related to Postglacial Rebound?”
    Chung, W. AGU 2000 Spring Meeting
    http://www.agu.org/cgi-bin/SFgate/SFgate?&listenv=table&multiple=1&range=1&directget=1&application=sm00&database=%2Fdata%2Fepubs%2Fwais%2Findexes%2Fsm00%2Fsm00&maxhits=200&=“S32A”

    “An intriguing observation in Greenland is a clear spatial correlation between seismicity and deglaciated areas along passive continental margins, a piece of evidence of earthquake triggering due to postglacial rebound. Another piece of evidence of induced seismicity due to deglaciation is from earthquake source mechanisms.”…”These and two prior events support the theory that the shallow part of the lithosphere beneath the deglaciated margins is under horizontal extension. The observed stress field can be explained as flexural stresses due to removal of ice loads and surface loads by glacial erosion. These local extensional stresses are further enhanced by the spreading stress of continental crust and reactivate preexisting faults. Earthquake characteristics observed from Greenland may be typical of those along the deglaciated passive margins elsewhere. ”

    Lateral viscosity variations beneath Antarctica and their implications on regional rebound motions and seismotectonics
    Wu, P. P.; Kaufmann, G.; Ivins, E. R. American Geophysical Union, Spring Meeting 2004, abstract #G33A-13 (05/2004)
    http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2004AGUSM.G33A..13W&db_key=PHY&data_type=HTML&format=&high=42d4f8714c16259

    …”Fault stability is predicted over much of Antarctica today, indicating that the seismically quite state is probably due to the presence of the thick ice. At the site of the 1998 Balleny Island Earthquake (Mw=8.1), the induced fracture stresses are relatively small by comparison, and interestingly become more prone to stress failure when a three-dimensional earth model is assumed.”

    Glacial isostatic stress shadowing by the Antarctic ice sheet
    Ivins, Erik R.; James, Thomas S.; Klemann, Volker Journal of Geophysical Research, Volume 108, Issue B12, pp. ETG 4-1, CiteID 2560, DOI 10.1029/2002JB002182 (12/2003)
    http://dx.doi.org/10.1029/2002JB002182

    “Numerous examples of fault slip that offset late Quaternary glacial deposits and bedrock polish support the idea that the glacial loading cycle causes earthquakes in the upper crust. A semianalytical scheme is presented for quantifying glacial and postglacial lithospheric fault reactivation using contemporary rock fracture prediction methods”…”A thick lithosphere, of the order of 150-240 km, augments stress shadowing by a late melting (middle-late Holocene) coastal East Antarctic ice complex and could cause present-day earthquakes many hundreds of kilometers seaward of the former Last Glacial Maximum grounding line.”

89. Steve Bloom Says:
    3 February 2007 at 4:23 AM

    Re #74: Dave, obviously the arithmetic error in the table is a bit embarrassing, but it’s really just another sign that the just-released document was itself still somewhat a draft. The point is that the substance of the document isn’t affected. I’m sure they’ll fix the problem pronto.

    Regarding your specific concern, I think the SPM made it clear that all that can be done now is to allow for sea level rise from 1) thermal expansion, 2) melt in place and 3) a more or less linear extrapolation of the small amount of dynamical melting that has been observed so far. While it is the expert judgement of many glaciologists that dynamical melting will accelerate very rapidly, there aren’t the needed models or terrain surveys in place as yet to be able to do more than make educated guesses. As a result, all that could really go into the AR4 was the vague statement to the effect that dynamical melting could make things much worse. Really I’m just re-stating what was said toward the end of the post, but hopefully I’ve made things a bit more clear.

90. pete best Says:
    3 February 2007 at 6:17 AM

    One other small point, we do not have anywhere near enough fossil fuels reserves to achieve the higher and hence more alarmist scenarios unless we invoke large scale positive feedback loops for large releases of CO2 from natural sources such as the siberian permafrost, or rain forests etc and as RC are always telling us the Science does not tell us that until temps reach 3 C above now. By 2030 Oil and Gas would have peaked and coal cannot scale to take there place so the REALITY of the climate situation is that we are going to get around 1 to a 2 C rise in temps as a maximum.

    So lets not get too alarmist about the doomed world.

    [Response: Would that this were true. There is more than enough coal to go to at least 4xCO2, depending somewhat on how fast you burn it, and if they figure out how to tap into seafloor methane clathrates, it could go even higher. What’s the support for your statement that “coal cannot scale to get there”? –raypierre]

91. Pat Neuman Says:
    3 February 2007 at 6:23 AM

    -
    Excerpt from interview transcript posted at Climate Science Watch website regarding sea level issue, BBC World News, February 2, 2007.
    -

    … Interview with Sharon Hays, Associate Director/Deputy Director for Science [OSTP] at the White House Office of Science and Technology Policy, leading the United States delegation, and Rick Piltz, Director, Climate Science Watch.

    BBC interviewer in Paris: �[Sharon Hays] told me what she learned:
    …

    BBC: And the sea level rise is one of the issues that is most contentious through the week. Many people have said, many people are saying that, what you�ve agreed is effectively too conservative, it�s too low, that sea level is rising quicker than what is reflected in this report.

    Hays: Right. What happened with this report is that the model projections we know don�t fully take into account the melting of the ice that we are seeing. And I think that the report dealt with this issue in a very a satisfactory way in that it reported the projections that the models have put out�and I should note that those models now have less certainty than they did in the p