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Climate Change Commitment II

Filed under: — gavin @ 2 June 2010 - (Español)

A couple of months ago, we discussed a short paper by Matthews and Weaver on the ‘climate change commitment’ – how much change are we going to see purely because of previous emissions. In my write up, I contrasted the results in M&W (assuming zero CO2 emissions from now on) with a constant concentration scenario (roughly equivalent to an immediate cut of 70% in CO2 emissions), however, as a few people pointed out in the comments, this exclusive focus on CO2 is a little artificial.


I have elsewhere been a big advocate of paying attention to the multi-faceted nature of the anthropogenic emissions (including aerosols and radiatively and chemically active short-lived species), both because that gives a more useful assessment of what it is that we are doing that drives climate change, and also because it is vital information for judging the effectiveness of any proposed policy for a suite of public issues (climate, air pollution, public health etc.). Thus, I shouldn’t have neglected to include these other factors in discussions of the climate change commitment.

Luckily, some estimates do exist in the literature of what happens if we ceased all human emissions of climatically important factors. One such estimate is from Hare and Meinshausen (2006), whose results are illustrated here:

The curve (1) is the result for zero emissions of all of the anthropogenic inputs (in this case, CO2, CH4, N2O, CFCs, SO2, CO, VOCs and NOx). The conclusion is that, in the absence of any human emissions, the expectation would be for quite a sharp warming with elevated temperatures lasting almost until 2050. The reason is that the reflective aerosols (sulphates) decrease in abundance very quickly and so their cooling effect is removed faster than the warming impact of the well-mixed GHGs disappears.

This calculation is done with a somewhat simplified model, and so it might be a little different with a more state-of-the-art ESM (for instance, including more aerosol species like black carbon and a more complete interaction between the chemistry and aerosol species), but the basic result is likely to be robust.

Obviously, this is not a realistic scenario for anything that could really happen, but it does illustrate a couple of points that are relevant for policy. Firstly, the full emissions profile of any particular activity or sector needs to be considered – exclusively focusing on CO2 might give a misleading picture of the climate impact. Secondly, timescales are important. The shorter the time horizon, the larger the impact of short-lived species (aerosols, ozone, etc.). However, the short-lived species provide both warming and cooling effects and the balance between them will vary depending on the activity. Good initial targets for policy measures to reduce emissions might therefore be those where both the short and long-lived components increase warming.


727 Responses to “Climate Change Commitment II”

  1. 251
    Ray Ladbury says:

    Rod B., you position is unscientific because rather than trying to understand data, you simply dismiss it with a handwave.

    If you ever actually produce any data…on anything…then we’ll see how I behave.

  2. 252
    Completely Fed Up says:

    “248
    Rod B says:
    7 June 2010 at 8:46 AM

    BPL (238) et al, you can really analyze the be-Jesus out of basic nonsense. Higher temps can increase GDP”

    Maybe they can, but in THIS reality, they don’t.

  3. 253
    Completely Fed Up says:

    “You will never get wheat from American plains grasses. This is because wheats such as bread wheat is a hybrid of three grasses from the Caucasian Mesopotamian regions (hexaploid).”

    Yes you’re right. Not sure how it changes things, but it’s new information. Just irrelevant to the case being made.

    You can breed the American plains grasses to produce wheat. It just takes much, much longer than 19 years to do it.

    After all, how long did it take to change those three grasses into modern wheat cultivars?

  4. 254
    Completely Fed Up says:

    “231
    Gilles says:
    7 June 2010 at 12:33 AM

    #219 : since i don’t know any “technological regime” in the modern sense that doesn’t make a massive use of FF”

    Why do you limit to a regime “in the modern sense”?

    US military couldn’t see any technology regime growing without access to IC silicon technology.

    USSR didn’t know that and they produced some very technological hardware using valves.

    Modern communications in 1980′s was impossible without wire access to POTS. Africa started modern communication systems using the improvements in technology that did away with wired phones for wireless access.

    Gilles would have counted that impossible 30 years ago.

    He would have been wrong.

    But his problem is that he has to limit himself so that he can frame the process into “We MUST have fossil fuels!!!”.

  5. 255

    #247 Rod B

    Thank you for the context.

    As to ‘mature’ how one views the maturity also requires context. I would say different aspects of climate science can be viewed as mature and immature.

    One can easily argue that the study of climate goes back to the beginning of the agrarian age, and one can argue that even hunter gatherers were aware and migrated based on that awareness.

    I would mark modern climate science since Fourier in 1824.

    Mature in the relevant context needs perspective. Modern rocket science is a fairly young science, in fact younger than climate science (since WWII). But we have already made it to the moon and beyond with rockets. Sure you could say it is immature, because we will know so much more in the future, but it is an argument that contains significant ambiguity.

    So I would say that because we can get a rocket to the moon and back with humans on board that modern rocket science is mature.

    Same with climate science. There are many things we are highly confident in and those things can be described as mature in this sense. There are lot’s of things that are still not understood well and those those areas can be said to be less mature.

    To say the whole of climate science not mature is to vague and lacks substance for perspective.

    Point of fact:

    - We know which gases are greenhouse gases.
    - We know we have added GHG’s to the atmosphere.
    - We know we have altered the radiative forcing inside the climate system.
    - We know all the maths and physics and models are in line with expectations.
    - We know the land and ocean temperatures are rising in accordance with the additional forcing.
    - We know how the natural cycle is supposed to work.
    - We know we should be in relative thermal equilibrium.
    - We know we are no longer in relative thermal equilibrium in the context of natural forcing minus human influence.
    - We know we are on a new climate path, that of warming.

    While we should, over many thousands of years, be heading toward our next ice age, we are not. We left the natural path and now we are on the path of warming, and by extrapolation, in relation to human infrastructure, it is relatively easy to see that this will be very costly.


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  6. 256
    Rod B says:

    Ray, the average US temperature dropped about 0.6 degreesC from 1940 to 1970. The US GDP had positive growth rates from about 6% to about 2% with an average of about 4% (not including the outlier of 8-10% in the midst of WWII). Somewhat in the ballpark of your negative correlation of temp with GDP, I guess. But then temp went up about 1.1 degreesC from 1970 to 2010. But, whaddayouknow, GDP was still positive from about 4.5 to 2.5% with an average of about 3.5%. Strangely it tapered off the last decade or so, about the same time temperatures took a hiatus — nowhere near your correlation ballpark.

    I haven’t done the mathematical correlation. Mostly because it’s a non-helpful exercise, would provide no useful knowledge about anything, and would be a waste of time.

  7. 257
    Septic Matthew says:

    228, Ray Ladbury: My objection is not to crop breeding, but rather to invoking it–or any technology–as a panacea. There are limits to what we can breed a crop to do.

    I do not “invoke” panaceas. You have erected another straw man. I propose multiple technologies to be developed and deployed simultaneously; I also propose that blithely asserting what can’t be done is useless. Even if you can’t breed rice to grow in Nebraska (CFU’s ludicrous counterfactual) in a short enough time to feed someone, there is no known reason that relatively robust varieties of manioc and potatoes can not be developed on the time scale of AGW. Salt-tolerant mangroves and lodge-resistant rice were each developed in less than 20 years.

  8. 258
    Completely Fed Up says:

    “Ray, the average US temperature dropped about 0.6 degreesC from 1940 to 1970.”

    This is not a trend.

    Climate is about the tendency of weather.

    “The US GDP had positive growth rates from about 6% to about 2%”

    Uh, you know what the US got in the late 1940′s?

    1) Europe war torn and no longer a power
    2) Industrialisation from the war effort
    3) No homeland attacks (therefore no build outs needed to recover)
    4) The biggee: the International Currency of Trade

    Being able to print your own money that the rest of the world have to buy unless they do no international trades is a big help in economics.

    Funny how you forget that.

  9. 259
    Completely Fed Up says:

    “Even if you can’t breed rice to grow in Nebraska (CFU’s ludicrous counterfactual)”

    But that has been your counter to how technology will fix all ™.

    And if these spuds can be manufactured, why have they not been manufactured now? There’s plenty of land that can’t be used because it’s marginal.

    But then you never read that point, do you. It’s devastating to your case.

  10. 260
    Completely Fed Up says:

    “I do not “invoke” panaceas. ”

    Yes you did, SM. You said warmer climate would be fine because we’d breed heat resistant crops.

  11. 261
    Jeffrey Davis says:

    re: 257

    “It could happen” is the equivalent of jumping off a cliff and hoping for a parachute to grow from your back.

  12. 262
    Charlie H says:

    #256, Rod B, re GDP and Temp Correlation…

    In addition to the change in temp, we had technological advances over a broad range of disciplines, population growth, immmigration (a/k/a “The Brain Drain” from the perspective of other countries), massively incrased foreign trade and a host of other factors. I’d like to see how you isolate temp to be the driver of GDP.

  13. 263
    John E. Pearson says:

    262: Charlie H: You wouldn’t happen to be the “Charlie H” who writes about EROEI and related topics?

  14. 264
    Ray Ladbury says:

    Septic Matthew, I did not say you invoked panaceas–that was Steckis who invoked breeding as the solution to all loss of food production. Even so, it is not at all clear how useful a technique developed during a time of climatic stability will be as climate becomes less and less stable.

  15. 265
    Ray Ladbury says:

    Tell ya what, Rod. You vector me to a peer-reviewed study that supports your thesis that decline in temperature was responsible for the economic growth, and I will read it. This is more than you bothered to do with the peer-reviewed studies I linked to that look for explanations of the GDP growth/tempurature relation. I guess reading the peer reviewed studies might have detracted from your outright denial of the data.

  16. 266
    Rod B says:

    Charlie H, you came in at the end of the movie. I (and others) have been saying correlations between temp and GPD is devoid of any substance.

  17. 267

    #255–

    John, you’d written earlier “So, it was probably a combination of Plass/Revelle/Keeling that ended the Pooh-poohing [of Arrhenius' climate work] I suppose.”

    Yes–but Bolin & Erikson 1958 was important, too, maybe the most important single result at that point in the game.

    http://wiki.nsdl.org/index.php/PALE:ClassicArticles/GlobalWarming/Article8

    That was the one that sufficiently nailed down CO2 sinking by the oceans (to oversimplify just a bit.)

    “Maturity” is a pretty undefined term WRT to the state of any given science, but this discussion shows, I think, that most of the major building blocks of the mainstream view of CO2 and climate have been in place for a half century now.

    Dr. Bolin, by the way, went on to serve as chairman of the IPCC. He died in 2007.

  18. 268
    Frank Giger says:

    Mr. Ladbury, I’m missing the links where temperature is the guiding light and determining factor for GDP.

    Shall we tell the Indians they’re peeing up a rope if they think they’re going to increase their GDP? Or at least tell them when they can expect it to stop growing based solely on the average climatic temperature?

    Similarly, if mean temperature is the cornerstone to GDP we can stop all funding in efforts to increase GDP by means of financial assistance and technologies transfers as it’s clearly not worth the effort.

    I’d think good governance (say, not having dictators and applying the rule of law as a crazy idea) would have far more impact on GDP than temperature. At a minimum we should try that first.

  19. 269
    Charlie H says:

    John E. Pearson,

    If you’re referring to something well thought out and carefully documented, no. If you’re referring to ranting nonsense on certain automotive sites then, likely, yes, it could well be me.

  20. 270
    Completely Fed Up says:

    Septic moans that he’s not talking of a panacea or “waving his magic wand” but he’s definitely invoking teh magic of teh biologies when he says:

    “The goal will be accomplished by trial and error, random variation and natural (or human) selection, as always.”

    Noting about whether the goal is feasible. After all, you can’t breed a dachshund from a banana, despite them both being long and thin.

    Oh, and we have to do that starting WHEN? Remember to keep enough time left over so we have the time for the trial AND the errors.

    And don’t worry, when he says “it will be solved”, this isn’t a panacea:

    “Panacea was said to have a poultice or potion with which she healed the sick. This brought about the concept of the panacea in medicine.”

    “panacea: a remedy for all diseases or ills”

    like climate change causing starvation. That’s an ill.

    Oh, and medicinal biology transgenically modified into plants.

    “It will happen”.

    Sound like a panacea to you?

  21. 271
    John E. Pearson says:

    269: Charlie:

    I was wondering if you might be Charlie Hall from SUNY-ESF.

  22. 272
    Ray Ladbury says:

    Frank, what is it with you and Rod that you can’t respond to empirical facts without turning them into a straw man? Would you kindly show me anywhere that I have even hinted that temperature is the single determinant of GDP?

    This is not controversial. It has been a longstanding puzzle in economics, and it has generated some interesting research. Basically the explanations advanced have had to do with 1)agricultural challenges, 2)endemic diseases, 3)difficulties of maintianing infrastructure in tropical and/or desert environments. Having lived in the tropics, I can attest that all three are operant.

    Again, I find it interesting that your first impulse is to gainsay the facts and attack a strawman of your own construction rather than try to understand them and see if they apply or not in a broader context.

  23. 273
    greyfox says:

    Ran across this at Climate Progress:

    Science stunner: Vast East Siberian Arctic Shelf methane stores destabilizing and venting
    NSF issues world a wake-up call: “Release of even a fraction of the methane stored in the shelf could trigger abrupt climate warming.”

    Comments?

  24. 274
    Ray Ladbury says:

    Rod and Frank,
    Again, on the off chance that you might actually be interested in learning something:

    http://faculty.arec.umd.edu/jhorowitz/Income-Temp-Draft-F.pdf

  25. 275
    Frank Giger says:

    I read the paper and there are a lot of holes in it – most of which the authors themselves point out.

    Why are the former Soviet bloc nations not on par with Western European GDPs? They share the same latitude, are geographically homogenous, and have the same climate and weather? If temperature drives GDP, then the economic power of the former DDR should be identical to the former FRG; hell, they’re the same country sharing the same climate and weather!

    Likewise, they stripped out international trade. Huh?

    There are so many caveats and exceptions (not including this country, adding in another to increase sample size) that it’s pretty weak.

    If we were to look at GDP for the Soviet Union/CIS from 1960 to 2010 we’d see a definate bend in the curve, particularly around 1990. Did the climate change that much?

    I remain unconvinced that the primary driver of GDP change is climate; governance (either benevolent, malevolent, or even anarchy) is far more important.

  26. 276
  27. 277
    Rod B says:

    Ray, I did too check your link.

    I never said a decline in temperature is responsible for economic growth. That’s what you were implying with your correlation talk — that being the same side of the coin as a rise in temperature being tied to economic reduction.

  28. 278
    ccpo says:

    greyfox says: 7 June 2010 at 7:55 PM

    Ran across this at Climate Progress:

    Science stunner: Vast East Siberian Arctic Shelf methane stores destabilizing and venting NSF issues world a wake-up call: “Release of even a fraction of the methane stored in the shelf could trigger abrupt climate warming.”

    Comments?

    A bit of old news hereabouts, but to answer your question from my personal perspective, how about I told you so?

    The problem is real. As we watch the Arctic Sea Ice melt away, and this year is looking to be a stunner, the entire Arctic becomes extremely vulnerable. We know there is methane seeping over large areas of the Arctic Ocean; we know the warming extends as much as 1500 km inland; we know the ice is not as thick and stable as satellites indicate; we know ice mass started nosediving around 1998 (was that El Nino year the tipping point everyone keeps talking about?); we know the land-based permafrost is also melting…

    http://climateprogress.org/2010/06/06/arctic-death-spiral-maslowski-ice-free-arctic-watts-goddard-wattsupwiththat/

    Really, what is there to say?

    Cheers

  29. 279
    Edward Greisch says:

    Another extreme rain event: “The three-day spell of extreme weather destroyed 11,000 homes and forced 200,000 people to evacuate, state news agency Xinhua reported. It also destroyed 15 reservoirs and thousands of irrigation networks.”
    http://www.enn.com/top_stories/article/41402

  30. 280
    Rod B says:

    Ray, I suppose one can analyze the beJesus out of macro things and can correlate and prove causality with damn near anything as long as the math utilized gets extensive and down to at least three significant figures and you throw enough parameters and pieces in the mix. But as a simple sniff test, if a 1.1 degreesC increase (roughly 1900 to 2000) causes a global GDP decrease of 4%, as your latest reference says, what the hell happened 1900-2000?

    BTW, I find no fault with doing such studies. There could easily be some interesting, even thought provoking, maybe even an AHA! moment (though that is a very long shot). I would encourage such studies; it’s how progress is made. However, I would discourage people from chomping down on the exact conclusions and swallowing them hook, line, and sinker as if they were published on edible stone tablets high on the mountain.

    If global temp increases 50 degrees, global GDP is pretty close to zero. Same, btw, if temp decreases 50 degrees. And it could be said that the temp change was at least the ultimate cause of the non-GDP. (Though I haven’t done any correlations or regression test or whatever on that, so I could be wrong.) But to buy into exact finite relationships on infinitesimal (relatively) scales simply has no credibility or cogency — even though the analysis might be interesting.

  31. 281
    J.S. McIntyre says:

    Septic: “I do not “invoke” panaceas. You have erected another straw man. I propose multiple technologies to be developed and deployed simultaneously.”

    Interesting. In reply, maybe some thought should be given to what you think you mean when you advance the idea of “development of technologies”

  32. 282
  33. 283
    Richard Steckis says:

    253
    Completely Fed Up says:
    7 June 2010 at 10:56 AM

    “You can breed the American plains grasses to produce wheat. It just takes much, much longer than 19 years to do it.”

    No you can’t. If you could then it would have already been done or at least attempted.

  34. 284
    Richard Steckis says:

    264
    Ray Ladbury says:
    7 June 2010 at 5:13 PM

    “Septic Matthew, I did not say you invoked panaceas–that was Steckis who invoked breeding as the solution to all loss of food production. Even so, it is not at all clear how useful a technique developed during a time of climatic stability will be as climate becomes less and less stable.”

    I invoked nothing of the sort. Plant breeding is only one string to the bow. You seem to think that all food production will be lost. I think it won’t. You are still engaging in extremist thinking (a severe cognitive distortion). i.e. climate change will destroy all agriculture, which is patently untrue.

  35. 285
    Gilles says:

    RL#241, NG#244 : although I posted a number of times here, you persistently misunderstood what I’m saying. I never said that “human civilization” as a whole was dependent on FF, and I agree to call “civilization” the greek, roman, chinese, aztec , etc.. who lived without them. I said that the modern way of life (a GDP and a energy consumption per capita several dozens times as large as previously) was only possible with FF.
    I have no objection if you want to give up this way of life and return to ancient times. It’s up to you (you can easily do it just now, basically by giving 90 % of your income to whom you’d like: you may still be richer that many people in the world).
    I say also that following all statistical methods you can imagine, all indicators of wealth will be much better correlated with FF consumption than with temperature . If you think I’m wrong, it is extremely simple to disprove me : show me a statistical method and an index that you consider well suited to measure human welfare, that i could blindly correlate to series of FF consumption and with temperatures, that would show a better correlation with temperature than with FF. If it is that obvious, it should be simple to find.

    Now your other reproach is : “you can’t postulate that we won’t be able to cope with the exhaustion of FF and replace them equivalently by renewables”. OK , but that’s exactly the same with temperature : you can’t postulate that we won’t be able to cope with any GW .

    And be logical : since everybody agree that countries using a lot of FF aren’t very sensitive to a global warming , and if FF can be replaced equivalently in the future, then why wouldn’t all countries benefit from this replacement in the future and cope with temperature exactly in the same way as we cope with it currently ?

    BPL :”BPL: As of 1850 or so, there hadn’t been anywhere anytime any developed country without whale oil.

    wrong of course. There is no quantitative criteria that showed at this time that a given way of life was dependent on whale oil. It was just a commodity used in some countries, but not all. Don’t be disingenuous please.

  36. 286
    JRC says:

    Comment by Frank Giger — 7 June 2010 @ 9:19 PM

    All that is being said, as simply as possible, is that increased rates of temps don’t mean that GDP will grow as someone said in the beginning. If anything increased rates of temps correlate to lower GDP, and the data proves that. I don’t think that anyone is saying it’s a universal law, but when someone claims that we will be better off with higher temperatures or a increased rate of warming they do not have the data to back it up. I like how people say that higher temperatures are good, but heat kills more people than any other natural phenomenon. I should cite a link, but I figure if I did you’d deny it anyway.

  37. 287
    CM says:

    Ray #274, the published version of Horowitz here for those with access: Environmental and Resource Economics 44, no. 4 (December 1, 2009): 475-493. DOI:10.1007/s10640-009-9296-2. Some changes from the draft.

  38. 288
    Completely Fed Up says:

    “If temperature drives GDP, then the economic power of the former DDR should be identical to the former FRG;”

    Ah, yes, the single-source mindset rears it’s hydra head again.

    GDP GROWTH, by the way. Not GDP.

    But look at it this way Frank, if communism is so bad and democracy/capitalism so good, why was the difference so small?

  39. 289
    Completely Fed Up says:

    “I (and others) have been saying correlations between temp and GPD is devoid of any substance.”

    No, you’ve been saying correlations between temp and GDP are in the opposite way of the measurements.

    “248
    Rod B says:
    7 June 2010 at 8:46 AM

    BPL (238) et al, you can really analyze the be-Jesus out of basic nonsense. Higher temps can increase GDP”

    “correlations … devoid of any substance” != “higher temps can increase GDP”.

  40. 290

    Having spent a fair amount of time in the tropics, as well as living in different cities with about the same range of temperatures, but entirely different cultures, I’m with Frank on this one — there are entirely too many variables to say that temperature and GDP have =any= relationship (except at the extremes).

    My guess is that the “cause” of this relationship is Western Europe being further north than the countries they invaded and colonized.

  41. 291
    Ray Ladbury says:

    Frank Giger, no one has posited that climate is THE primary driver of GDP. THAT is the straw man. The contention is that increasing temperature influences economic growth negatively, and the data support that. The data certainly do not support the contention that a warmer world will be a paradise–and THAT is the contention I was countering with the data.

  42. 292

    Rod B 256: I haven’t done the mathematical correlation. Mostly because it’s a non-helpful exercise…

    BPL: Or because you prefer picking out areas of the curve that look “interesting” to you and gassing about them.

  43. 293
    Didactylos says:

    CFU:

    I made a mistake responding to you. I should have known you would merely dismiss the problem and be rude, irritating both me and the world at large.

    I wish this blog had a way to filter out the noise. And by noise, I mean rude and ill-considered comments like nearly all of yours, CFU. You are ten times worse than a denier.

  44. 294

    FG 268: Mr. Ladbury, I’m missing the links where temperature is the guiding light and determining factor for GDP.

    BPL: He didn’t say it was. He was just saying the claim that warmer temperatures will make us more prosperous was empirically wrong. What correlation exists between the two is negative, not positive.

    FG: Shall we tell the Indians they’re peeing up a rope if they think they’re going to increase their GDP? Or at least tell them when they can expect it to stop growing based solely on the average climatic temperature?

    BPL: When their agriculture fails, their economy will go with it. Abruptly.

  45. 295

    FG 275: I remain unconvinced that the primary driver of GDP change is climate

    BPL: Hello? Hello? FG, are you reading us? You don’t appear to be receiving our communications. Can you step up your gain? Repeat, can you step up your gain?

    NOBODY SAID CLIMATE IS THE PRIMARY DRIVER OF GDP CHANGE. But when you get a climate DISASTER, as we’re likely to do in this century, the GDP will be affected. Do you understand the difference in the two concepts?

  46. 296
    dhogaza says:

    Frank Giger:

    I remain unconvinced that the primary driver of GDP change is climate; governance (either benevolent, malevolent, or even anarchy) is far more important.

    In other words, you agree with Ray’s point:

    Denialist claims that a warmer earth would be a more prosperous earth have no basis in fact.

    Cool.

  47. 297
    Nick Gotts says:

    If temperature drives GDP, then the economic power of the former DDR should be identical to the former FRG – Frank Giger

    Don’t. Be. Silly. No-one is claiming that temperature is the sole determinant of GDP. How many times does that need to be repeated before you stop pretending they are? If you give me an estimate, I’ll provide a post repeating it the requisite number of times.

  48. 298

    @275 Frank : are you being willfully stubborn? Please show where *anybody* claimed that climate was the primary driver for GDP? What was said was that climate appears to influence GDP to the tune of 1.1% of GDP per degree of warming, not that there are no other factors influencing GDP. You are attacking a straw man of your own construction, everybody here (except perhaps Rod) can see this and it ain’t doing your credibility much good…

  49. 299
    Completely Fed Up says:

    D, you made the mistake that you were making sense. you made the mistake of not answering the counter. you made the mistake of thinking that I would care you’re “on my side” when you make a dumb argument.

  50. 300
    greyfox says:

    Thanks for the updates. It seems to me that this might be the game changer. It actually concerns me more than the sum of the other issues combined, inasmuch as it would appear that the human contribution to warming may have been just enough to tip something really huge, fast and really deadly. In fact, it may make much of the detail quibbling moot. I suspect that it is in fact going to be a large story relatively soon, and will make denialist rubbish vanish.


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