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  1. All good. So how do we get to realistic probability distributions of outcomes? They are needed…

    Comment by Glen Fergus — 20 Aug 2007 @ 6:57 PM

  2. Are there any model predictions (simulations?) for temperatures round 1800 and before?

    Comment by Osvaldo Lucas — 20 Aug 2007 @ 7:21 PM

  3. Do we ask too much of models?

    I think it’s fair to say that we’ll never see a perfect one except the planet system itself. That doesn’t mean or imply that models are not helpful, or needed. They may, however, never meet all the demands that have been placed on them, including by the debunkers who want all action delayed until the perfect model or ensemble is at hand.

    Actually, despite limits demonstrated for accuracy of rate and extent of change, the models deserve some cheers for pointing in the direction we’re headed. And that should be warning enough to set us on a course correction.

    Comment by Lance Olsen — 20 Aug 2007 @ 7:22 PM

  4. Re 1
    The realistic, probability-distribution models will come after we have made our decisions the old-fashioned way – on the basis on incomplete and mostly wrong information.

    There is so much social inertia and so many lags and delays in climate systems that we may already have made critical decisions; and not yet realize that we have already past those decision points.

    Here, I would cite Beyond the Limits by Meadows, Meadows, and Randers, & earlier works by Jay Forester, Meadows, and Meadows going back into the Club of Rome Report and Limits to Growth.

    (Dynamo was not a good language to program in, but it was better than Formula Translation Language.)

    Comment by Aaron Lewis — 20 Aug 2007 @ 7:49 PM

  5. His definition adds unnecessary confusion and misses the main point of a “tipping point”, which is that it’s a value where the system you’re describing abruptly shifts from negative feedback to positive in some range of conditions.

    If you have a normal thermostat, for example, the heater goes on when the temperature falls and turns off as it rises (“negative feedback”, a feature which tends to keep things stable.) If there were a bad design flaw in a thermostat, such that temperatures over 100 F turned the furnace on, that room’s climate would have a tipping point ~100 F and the room would get hard to cool whenever temperatures rose over that (“positive feedback,” at least for awhile.) It wouldn’t necessarily get hotter & hotter until the place burned down; the furnace would have limits & eventually a cold enough night would bring things back to normal, but that 100 F mark would be well worth avoiding…

    Comment by Forrest Curo — 20 Aug 2007 @ 8:02 PM

  6. Regarding the Sahara and the Sahel, this news article addresses that in some depth, and even provides a good example of the model ensemble business, and why a ‘model outlier’ might actually be correct.

    In particular, Isaac Held’s group produced model results that indicated that the Sahel wouldn’t be greening but instead would be facing a period of continued drying. They also have a more recent follow-up paper with a statistical approach.

    On the other hand,
    “Last year (2005) US-based researchers Martin Hoerling and James Hurrell looked at all of the most recent climate models, averaged them out, and came to the conclusion that the Sahel’s recent fate would be reversed in the 21st century.” (Note that their analysis predicts increased drought for southern Africa, however).

    The article also finds yet another way to bring tipping into the discussion:
    “To complicate matters, the relative importance of factors affecting the Sahel’s climate is tipped in different directions by the different models.”:)

    Unfortunately, this is a topic that sites like Sherwood Idso’s Western Fuels Association-linked CO2science have jumped on (guess which outcome they’re promoting: greening or drying?). That site seems to do more deliberate distortion of scientific publications than any other.

    Given all this uncertainty, what should policy makers do? There must be something in the ‘policy makers guidebook’ that relates to serious uncertainty – something like : hedge your bets and start some contingency planning for the worst-possible-outcome scenario – just to be on the safe side. There are some more obvious steps – since deforestation in the region has played at least some role, one goal should be to do everything possible to halt and reverse that trend (saving forests appears to be more important than producing biofuels, as well).

    Comment by Ike Solem — 20 Aug 2007 @ 8:03 PM

  7. Very interesting article by Tim Lenton on tipping points. I note that Tim sees the loss of the Greenland Ice Sheet as the most likely Tipper – giving us 7m sea level rise over the next 300 years or so.

    While he discusses the interaction between the GIS and the WAIS, in his summing up he does not tie the loss of GIS to the WAIS in the way he does in the body of his report. But it seems he is saying that it is most unlikely we will be able to avoid the loss of the GIS (+7m rise), and he means that we will then loose WAIS (4-6m rise) as well – the two will be trundling into the ocean together, as we frantically withdraw our civilisation from the coast.

    With the prospect of 11 to 13m rise over 300 years, it makes well over +1m rise this century seem very very likely, doesnt it? (13m/300 years comes to over 4m/100 years on average. I know it wont be linear, but its going to go with a hiss and a roar, eh!)

    http://www.nasa.gov/vision/earth/lookingatearth/arctic-20070515.html

    And isnt this well above the politically-correct IPCC predictions?

    Comment by Nigel Williams — 20 Aug 2007 @ 8:04 PM

  8. The skeptics of GW and AGW often say: processes in nature always try to return to equilibrium instead of runaway amplification, so nature will be take care of it. That is simply false. Look at gravitational collapse, stability of objects in flight unless specially made with canard wings etc., the rust process (more rust makes rusting even easier by opening up surface pits) etc.

    Comment by Neil B. — 20 Aug 2007 @ 8:49 PM

  9. In message 7 above, Nigel Williams expresses something of the cognitive dissonance I’ve felt in trying to sink my teeth into this issue: who is addressing the disconnect between IPCC projections and ice-sheet observations? Luckily for lost, confused souls such as myself, James Hansen (who is a great guru not only among scientists but also among philosophers) has done a fine job, in my humble opinion.

    http://pubs.giss.nasa.gov/docs/2007/2007_Hansen_etal_2.pdf

    This review, entitled “Climate Change and Trace Gases” cuts to the chase with remarkable frankness. The “Albedo Flip” Hansen et al warn of is, substantially, what’s going on now (a decade or four ahead of schedule) in the Arctic. So there we are, I suppose.

    But, you say, this article only demonstrates Hansen’s singular genius in his chosen field of climatology. What of my claim that Hansen is also a philosopher of unique insight?

    http://pubs.giss.nasa.gov/abstracts/2007/Hansen.html

    This paper, called “Scientific Reticence and Sea-Level Rise” is one of the more thoughtful treatments you’re likely to see of the problem: why is a large, consensus organization (such as the IPCC) more likely to underestimate the scope of future disasters?

    Comment by Daniel C. Goodwin — 20 Aug 2007 @ 9:44 PM

  10. There are some important distinctions between Bayesian and Frequentists statistics. What I find refreshing about casting an answer to a question in terms of Bayesian statistics is that one’s assumptions are explicitly part of the answer. Some questions are better answered without pretending there is an absolute probability of being right or wrong. For the problem of climate model parametric uncertainties, one should regard the resulting Bayesian probability as a relative likelihood given the parameters considered and one’s prior assumptions. If one wanted to express no particular preference for a prior for a parameter x, a uniform probability may suffice. However, if the parameter were 1/x then a more appropriate prior (that expresses no particular preference) should be a Gamma distribution. Climate model ensembles can be constructed to reflect exactly what we mean to express in terms of sources of uncertainty.

    Comment by Charles Jackson — 20 Aug 2007 @ 10:50 PM

  11. The problem is genetic. The average human is just not good enough in math to survive the next 200 years. My browser can’t read the Economist web site, but my guess is, you shouldn’t expect accountants to do math. The problem with democracy is, we all get the government the average deserves. The average may “deserve” extinction, or “deserve” is a bum concept.
    I think I know why ET hasn’t arrived yet. His planet died because of global warming before he could get off of it. The end-Permian extinction made it into NASA’s Astrobiology zine. See:
    http://astrobio.net/news/modules.php?op=modload&name=News
    &file=article&sid=2429&mode=thread&order=0&thold=0
    The Astrobio article refers to the end-Permian as a carbon cycle problem.
    The points Gavin makes are mathematical and way beyond the comprehension of not just the average, but all but the top 0.1%. Even the top 0.1% can’t understand it unless they received the proper training. Gavin is talking to physicists and mathematicians but publishing to the world. Everybody needs to understand what he says. This is an impossible bind. We need to do a million years worth of evolution in the next 5 years.

    Comment by Edward Greisch — 21 Aug 2007 @ 1:14 AM

  12. Hi Gavin,

    I certainly don’t want to belittle anyones models but I had an interesting conversation last week in California. A computer modeler was explaining to me how models can be wrong. I acknowledged that he is right and computer models can be wrong.

    Then I said, forget all the computer models. They are becoming increasingly irrelevant to the argument of global warming. They are important for understanding things and predictive quality but it’s getting warm outside. Everyone feels it. Everyone says hey this weather seems quite different than when I was young.

    For myself, I remember in Big Bear Lake when they could ice skate on the lake in winter and skiing went until July 4th (that was only around 37 years ago).

    People are arguing about whether the glaciers are melting. Well, the pictures don’t lie. http://www7.nationalgeographic.com/ngm/0706/feature2/

    When I’m in Switzerland I visit glaciers and its interesting that all these spots have picture of how big the glaciers were before. The amount of shrinkage is striking.

    The fact is that we are getting more Category 5 Tropical Cyclones than ever before. I’ve been watching the SST’s lately and hearing everyone talk about how were not going to get to many hurricanes this year. But it is well known that sea surface temperature drives hurricanes. It takes temps over 28.5 C to get a hurricane but the temps in the gulf today are showing way above that averaging near 30 C. http://www.osdpd.noaa.gov/PSB/EPS/SST/data/FS_km50f100.gif
    http://polar.ncep.noaa.gov/sst/ophi/Welcome.html

    As far as the argument goes, I think we are getting beyond models. The sad thing is that if the exponent of acceleration continues as it seems to be doing in the real time data. When the policy makers wake up we will be facing the front of a wave that will seem overwhelming and it will be.

    I continue to hope that we wake up faster as it no longer seems a matter of if it’s too late but rather that we are going to be in damage control for some time to come and all that that implies. I have this message for those that are questioning the veracity of reason or, by some fluke of neuro-chemistry, still doubting that global warming is real. Good luck!

    Comment by John P. Reisman — 21 Aug 2007 @ 2:02 AM

  13. “And isnt this well above the politically-correct IPCC predictions?”

    I’m growing increasingly sceptical about the IPCC’s conclusions wrt sea level rise. Hansen et al think there is good evidence for a 7m rise by the end of the century unless urgent action is taken. Given that the IPCC’s report doesn’t factor in Greenland or the West Antarctic ice sheet owing to their complexity, Hansen’s report seems far more convincing – unfortunately. I’d be very interested to see a response from one of the climatalogists.

    James Hansen et al, 2007. Climate Change and Trace Gases. Philiosophical Transactions of the Royal Society – A. Vol 365, pp 1925-1954. doi: 10.1098/rsta.2007.2052. http://pubs.giss.nasa.gov/docs/2007/2007_Hansen_etal_2.pdf

    Comment by Bill Tarver — 21 Aug 2007 @ 2:49 AM

  14. Sorry I have not had time to read all the reactions above, and apologies in advance if this repeats anything. However, I think a lot can be achieved by noting the errors in our models (however calibrated), and ‘bootstrapping’ our forecasts. Thus we can include both our parameter (and indeed any other ratio factor) uncertainties and our calibration uncertainty, building ensembles of results for individual models, and hence ensembles of ensembles etc. There are lots of ways of dealing with being cautious with the prediction errors (include jackknifing with the bootstrap, for example – see Davison and Hinkley, 1997) and establishing the extent of equifinality (or convergence if you prefer), and hence to begin considering how much is model artefact, how much is error, and how much is at heart a forecast that we need to take notice of. Nick O.

    Comment by Nick Odoni — 21 Aug 2007 @ 4:45 AM

  15. Thanks for the article. Very interesting!

    Comment by cce — 21 Aug 2007 @ 5:10 AM

  16. With regard to Tipping Points, is the 300 year timeline at 382 ppm of CO2 or the project(BAU)scenario of 550 ppm. Is there enough CO2 currently in the atmosphere for Greenland and WAIS to experience this non linear phenomena ?

    Politically this 300 year time line is a joke.

    Comment by pete best — 21 Aug 2007 @ 5:41 AM

  17. For feedbacks capable of becoming tipping points, don’t forget greenhouse gases in melting permafrost.

    Comment by Barton Paul Levenson — 21 Aug 2007 @ 5:52 AM

  18. I noticed the ‘tipping points’ were all localized. Calling them “large scale” is meaningless, they are either local or global. Often the tipping point proponents here will point to such local phenomenon and imply that the whole earth will get warmer. What they forget is there are negative feedbacks elsewhere, particularly in the weather in a wetter world. Tim pointed one out in the Sahara. That does not mean I believe that Gaia will magically regulate the climate, far from it. There will be local tipping points particularly at the poles where CO2 has the greatest warming effect. For the earth as a whole, doubtful.

    Comment by Eric (skeptic) — 21 Aug 2007 @ 6:00 AM

  19. Daniel, thank you for those pointers. I had read the first paper, and the one on Reticence is entirely pertinent. Im a transportation planner by trade, and I try and get other engineers to move towards using more sustainable modes of transport. Regrettably not too many are prepared to recommend to their clients that they use horses and carts to build their next skyscraper or dam.

    Everything I have read of Hansen et al lately, and everything that the community is reporting in relation to our declining global climate’s critical parameters points to the same point: A very wet year 2100 for a huge part of humanity.

    I notice that even Hansen is prone to ‘reticence’ as he tells us things will be fine if we sequester virtually all of virtually every greenhouse gas immediately. I think it was in the movie The Princess Bride where – presented with a total load of lies about his future (It was going to be bad) the hero said to his antagonists “We are all gentlemen here..” making it clear that he knew rubbish when he heard it, and thy all knew the truth.

    Hansen has made the same observation among his peers. We ARE all gentlemen here. Frankly the time for being polite is past. So what we loose some funding, or loose out jobs if we speak out. Perhaps the more practice we get making do with less will stand us in good stead before too long!.

    Comment by Nigel Williams — 21 Aug 2007 @ 6:30 AM

  20. As always a cogent explanation followed by a rousing and intelligent discussion. Exactly why Real Climate is the best climate site around. Slightly off topic, news of this article “Heat Capacity, Time Constant, and Sensitivity of Earth’s Climate System,” by Brookhaven National Lab scientist Stephen Swartz soon to appear in the journal of Geophysical Research is already making the rounds on the skeptic blogs as the final nail in the coffin for AGW. No one has been able to tell me what it actually says though. Any insights from this learned crowd?

    Comment by Doug Lowthian — 21 Aug 2007 @ 7:47 AM

  21. Re: my previous post: The paper in question is available in a preprint at http://www.ecd.bnl.gov/steve/pubs/HeatCapacity.pdf
    Thanks for any comments. My skeptical friends are crowing that this kills the AGW theory. I’m not so sure..

    [Response: You want http://julesandjames.blogspot.com/2007/08/schwartz-sensitivity-estimate.html - William]

    Comment by Doug Lowthian — 21 Aug 2007 @ 7:54 AM

  22. Re #18 where Eric the Skeptic says:

    There will be local tipping points particularly at the poles where CO2 has the greatest warming effect. For the earth as a whole, doubtful.

    The problem is that the global climate is inter-connected. The atmosphere is like a water bed. If you increase the pressure in one place it will pop up somewhere else.

    When the Arctic summer ice disappears, the sea will get warmer and the air will contain more water vapour. This makes it lighter and it will start rising instead of falling in the polar vortex. As a result the Northern hemisphere circulation pattern will be disrupted, and that will overflow into the Southern Hemisphere. Changes in the Arctic air flow could result in changes to the Indian and east African monsoons, El Ninos, and the ITCZ.

    Of course all those changes might not be bad, but if it caused the west African Monsoon to restart and return the Sahara into a bread basket, how are we going to get the farmers and farm machinery from the new US Mid-West desert across to Africa quickly enough to prevent a famine?

    Comment by Alastair McDonald — 21 Aug 2007 @ 8:30 AM

  23. RE #18 [I noticed the ‘tipping points’ were all localized.] Some of these “local” (but large-scale) events would have global effects. Among those mentioned in the article the Amazon die-off and the change in the amount of Arctic sea ice are the most obvious over the medium term: the first would lead to a large pulse of greenhouse gas emissions as trees burned and further emissions as soil carbon was released; the second to a change in albedo which would accelerate warming. The greening of the Sahara would presumably have a global effect in the opposite direction (though perhaps not if secondary effects are taken into account: Saharan dust is thought to have an important fertilising effect on the Atlantic and the Amazon). Although it falls outside the article’s definition of a “tipping point”, the release of methane from melting permafrost would have a global effect.

    Comment by Nick Gotts — 21 Aug 2007 @ 8:40 AM

  24. Re #12

    What is the source for more Cat 5 hurricanes? the Hurricane center has denied any such claim and frankly, they’d know.

    As for computer models… for a decade people have been saying “the models are RIGHT”. now models don’t matter? why is that? because the models aren’t predicting the gloom and doom anymore?

    as far as the 10% comment in the original story goes, if 90% of the models predict no change and 10% predict devastation, then something is wrong somewhere. while science isn’t dependent on consensus, the peer review process does work by developing consensus among knowledgeable people. yes, the 90% may be wrong, but rarely is that the case. when it is the case, i’ll admit that it’s very visible (Galileo comes to mind)

    Comment by dean — 21 Aug 2007 @ 8:58 AM

  25. One thing I’ve noticed is that many of us use the oven analogy. One major flaw with this analogy is that our system isn’t temperature based, it’s time based. the oven’s on for a set amount of time. It makes a lot more sense to think of the world this way… it also is easier to envision the ‘tipping point’.

    Comment by dean — 21 Aug 2007 @ 9:01 AM

  26. Eric,
    A volcano like the Yellowstone eruption can be considered a point source, geologically. Yet it has global and long term effects.

    Doug,
    I haven’t had time to peruse the paper thoroughly, but it would appear to be quite full of questionable assumptions. The values for climate sensitivity and equilibrium response appear to contradict values determined from a variety of other lines of evidence. I would also question his treatment of climate relaxation using “fluctuations” about an equilibrium. Instead, we have a system disturbed from equilibrium by forcer that increases with time. He also conveniently ignores positive feedbacks (e.g. increased water vapor) and most of the actual physics of climate change. The goal of physics should be, we are told, to make a model as simple as it can be and no simpler. It appears he has gone overboard on simplification, so it is not surprising that he is getting absurd results. I’m kind of surprised this got published.

    Comment by Ray Ladbury — 21 Aug 2007 @ 9:29 AM

  27. Doug Lowthian wrote at 21 Aug 2007,7:54 AM
    >http://www.ecd.bnl.gov/steve/pubs/HeatCapacity.pdf

    i looked at the paper and i see some simplifications:
    1)the outgoing longwave emission is stated to vary as the fourth power of the
    _surface_ temperature. Should this not be the temperature at the radiating surface at the top of the atmosphere ?
    2)there is an assumption of linearity made in eq. 5. i am not sure this will hold
    3)the para before eq 16. admits that there are significant changes in the heat content of the ocean, and posits that the only causes could be variation in planetary albedo or effective emissivity; this is not clear to me since there are other components to the climate system such as icesheets which can sink considerable amounts of heat as well.

    it appears at first reading that some possibly important physics is left out of this model. Perhaps some of our resident climate modellers would care to comment ?

    sidd

    Comment by sidd — 21 Aug 2007 @ 9:29 AM

  28. “Re: my previous post: The paper in question is available in a preprint at http://www.ecd.bnl.gov/steve/pubs/HeatCapacity.pdf
    Thanks for any comments. My skeptical friends are crowing that this kills the AGW theory. I’m not so sure..”

    I’m not so sure either. The paper never mentions feedbacks. He concludes that a doubling of CO2 will cause a temperature increase of ~1.1 degC and contrasts this with the IPCC report that gives an equivalent figure of 3 deg C. But didn’t that figure also take into account the several feedbacks?

    Comment by Bill Tarver — 21 Aug 2007 @ 9:42 AM

  29. Re 18, where Eric says there will be local tipping at the poles,particularly at the poles,but doubtful for the whole Earth.

    Melting of Greenland and West Antarctic ice sheets will raise sea level globally. Melting of Greenland ice would dump large amounts of fresh water into the north Atlantic affecting the Atlantic thermohaline circulation pattern. As was pointed out earlier, the release of CH4 from melting permafrost would be distributed pretty evenly throughout the atmosphere and not remain local. A number of such area wide warming events,will have global consequences.

    Comment by Lawrence Brown — 21 Aug 2007 @ 10:18 AM

  30. Re: #20, #21

    Yes I’ve seen Schwartz’s paper.

    He estimates the heat capacity of the global climate system, and uses historical temperature data to estimate the “characteristic timescale” of temperature change. Using these data, he claims to derive the climate sensitivity, getting a figure of 1.1 deg.C for a doubling of CO2. This is much less than the current “best estimate” of about 3 deg.C, and would imply that there is *not* any unfelt warming “still in the pipeline” from greenhouse gases we’ve already emitted.

    Even if his result is correct (which it isn’t), it by no means “kills AGW theory.” It simply changes the numbers. In fact, Schwartz’s analysis implicitly assumes that the planet *is* warming, and that the primary cause is man-made greenhouse gases.

    His work depends on (among other things) the assumption that there’s only *one* characteristic timescale for global climate. Physically this would seem to be impossible; each component of the climate system (atmosphere, ocean, cryosphere) will necessarily have a different characteristic timescale. Schwartz’s analysis depends on the fast response of the atmosphere to climate forcing, but quite ignores the slow response of oceans and other components.

    The really odd thing, for me, is that mathematically, the data themselves contradict his hypothesis of a single timescale for climate response. I believe I can show, beyond doubt, that the data he presents *reject* the idea of such a simple behavior, but Schwartz presents an argument (which I regard as invalid) that they confirm it.

    I’m considering writing it up for JGR, and also considering doing a blog post on the subject.

    Comment by tamino — 21 Aug 2007 @ 10:21 AM

  31. What are some examples of climate tipping points from the past that demonstrate what actually happens when a tipping point is reached?

    Comment by paul — 21 Aug 2007 @ 10:22 AM

  32. Ooops, that’s a link to the original paper – James’ comments are actually here:
    http://julesandjames.blogspot.com/2007/08/schwartz-sensitivity-estimate.html

    Comment by SomeBeans — 21 Aug 2007 @ 10:22 AM

  33. That’s the same value for climate sensitivity I’ve seen from the string theory physics site and from knowledgeable climate sites as well — it’s the number people get this way: calculated in the absence of any feedback, on the hypothetical twinning of each molecule of CO2 in the atmosphere to make two where there were one, instantly, and having nothing else happen.

    Nice in theory. Of course, if it were possible to cut the total amount of CO2 in the atmosphere by half without any other event occurring, this also would solve a lot of problems. Perhaps pulling on the strings in exactly the right way through the fifth dimension somehow would do it. Til then it’s just a hypothetical.

    The rest of the climate sensitivity above the about 1 degree C is tied to the obvious questions: where does the CO2 come from, and where does it go, and over what time period.

    Comment by Hank Roberts — 21 Aug 2007 @ 10:24 AM

  34. As best I can read the tipping point defn. and comments (and I’m sure I haven’t quite got it), “crucial feature” 1) describes or defines a region of the global system that when subjected to a small change in the short run suffers a large change in the long run because of an abrupt shift in the sign of its feedback and 2) transfers the large change/long run effects to other regions, so as to significanly affect the larger global system.

    Having my brain insisting that every “crucial feature” be something I can point to on a world map is probably not helping me understand. And I have no idea what to make of “parameters controlling the system can be transparently combined into a single control.”

    Anyway, the whole reason I’m even interested in the defn. (which I assume is intended to be read by someone with technical knowledge of climate modeling jargon) is that I’ve started wondering about how climate models handle volcanoes or geology like the Yellowstone caldera–regularly emitting “point sources” that transfer their climate effects globally. And what (if anything) makes geological emissions from Yellowstone different from man-made emissions from Taiwan or L.A.?

    Comment by A.C. — 21 Aug 2007 @ 10:46 AM

  35. So glad you’re getting around to talking about (I know you hate this :)) the Venus effect, runaway warming…(note, I did not say “permanent runaway warming”).

    The Venus effect is meant to be an analogy (of course, we all know Earth is not Venus), and analogies are only similar in some aspects and to some extent. For the totally unrefined layperson, it is a way to grasp an idea that GW may not be linear (which I sorta think most people are assuming & that we have plenty of time), but may zoom up to big harm, before the climate gets back to today’s temps 1000s of years from now.

    I think scientists prefer the term “hysteresis” for this, because that contains the meaning that the climate eventually levels off (after wiping out much of life) and cools back down again.

    But, I think most people would be more focused on the upswing in GW than its eventual retreat. Except the denialists, who’d probably claim, “Well, that wasn’t so bad, some 30,000 people survived 100,000 years later, and now are back to repopulating the earth with all that great fossil fuel from the anthropocene die out.”

    Comment by Lynn Vincentnathan — 21 Aug 2007 @ 11:09 AM

  36. A.C.
    A dynamical system will respond differently to a point source than it will to a diffuse system. Likewise, a steady perturbation will have a different effect than a delta function in time. Think of it this way: In the vicinity of a Yellowstone type event, the local changes will be drastic, and hence there may be a significant difference in how efficiently these changes are transmitted to the global system–e.g. you may have a significant local temperature drop that results in rainshowers that take at least some of the dust and sulfates out of the air, etc.
    In addition, a volcano emits LOTS of sulfates, dust and other nasties in addition to the CO2. Finally, averaged over time, volcanos produce far fewer ghgs than do humans.

    Comment by Ray Ladbury — 21 Aug 2007 @ 11:29 AM

  37. Regarding “Scientific Reticence” – Nigel Williams, in post 19 above, points out that Hansen et al engage in a bit of the same at the end of “Climate Change and Trace Gases,” where they conclude that sequestering emissions from biofuels is a means of drawing down atmospheric co2. This also strikes me as a bit pollyannish. It would work (if gradually) if the population of the earth were considerably smaller, I suppose. Nobody wants to be accused of being a doomsayer, and so reviews of this nature tend to search (if pathetically) for some ray of hope to grab onto, for some positive message to conclude with, no matter what the state of the evidence.

    Compounding the clumsiness of this obviously inadequate suggestion, the paper concludes on a puzzling footnote, with a whiff of cloying, desperate patriotism:

    The potential of these ‘amber waves of grain’ and coastal facilities for permanent underground storage ‘from sea to shining sea’ to help restore America’s technical prowess, moral authority and prestige, for the sake of our children and grandchildren, in the course of helping to solve the climate problem, has not escaped our attention.

    Just goes to show that even geniuses experience lapses of judgment from time to time…

    Comment by Daniel C. Goodwin — 21 Aug 2007 @ 11:43 AM

  38. RE #12 (John P Reisman): With all due respect, I would disagree with your view that we should forget the models. Yes, the models are imperfect, but that does not mean they are worthless. They are useful, first, to show the causes of the current warming – the comparison of outcomes for natural vs. anthropogenic forcinigs is a powerful argument for AGW. They are also useful to point to what the effects of AGW probably would be. The predictive power of the models does depend on checking them against what is actually happening – and this will be more important when the feedbacks start kicking in (but by then maybe we won’t need the models to tell us we are bad off). I am concerned that the deniers/skeptics use the imperfection of the multiple lines of evidence as a tool to argue against an anthropogenic cause for GW – I see this happening in the current arguments against the surface data. Yes, we can acknowledge the limitations of each line of evidence and of the models, but it does not help us if climatologists abandon these useful tools.

    Comment by Deech56 — 21 Aug 2007 @ 11:58 AM

  39. Re: 35

    Venus and run away global warming. Here’s a serious look at it:

    http://personals.galaxyinternet.net/tunga/DefectiveGlobalWarming.pdf

    “Why is the albedo of Venus important? When the albedo is at 0.80, the Global Warming Theory falls apart. . .

    The carbon dioxide levels on Earth have risen from approximately 0.028% to 0.036% in the last few decades. It is a major stretch to compare this with Venus at a 96.500% carbon dioxide level and promote an uncontrollable runaway condition. Earth in its early history, 385 million years ago, had an atmosphere with 10 times the present carbon dioxide levels. Those elevated levels did not produce runaway global warming then, so why should we theorize that it would today?”

    Comment by quadszilla — 21 Aug 2007 @ 12:16 PM

  40. > cloying, desperate patriotism

    Er, no. Belated acceptance of responsibility for cleaning up the mess that we profited from, by profiting from being the first to come up with the solutions, so we can sell them overseas.

    He knows Americans want to do well by doing good.

    Comment by Hank Roberts — 21 Aug 2007 @ 12:19 PM

  41. Re #24

    Hi Dean, while data in NHC, NOAA, NASA, NCAR and other .gov web sites is scattered, the NHC does have a nice paper on the subject including the following:

    Research has shown that the sea surface temperature (SST) alone does not provide a good indication of whether a storm will intensify. (See, for example the SST/Intensity relationships of recent Atlantic tropical cyclones.) However, SST does provide an upper limit to storm intensity. In SHIPS, the Maximum Possible Storm Intensity (MPI) is related to the SST by the equation:

    MPI = 55.6 kt + 108.5 kt exp[0.1813 * {SST - 30.0oC)]

    http://www.srh.noaa.gov/ssd/nwpmodel/html/nhcmodel.htm

    One of the strongest observed correlative facts is that we are getting more of those ‘rare’ cat. 5 hurricanes, and the water is warmer. Let me know if you have another good explanation for the increase of cat. 5 hurricanes. I’m all ears on that one!

    Also, could you please show me a link where they claim that their own research is incorrect on this matter. Maybe there is a contextual dilemma?

    “As for computer models…” What I said was: “They are becoming increasingly irrelevant to the argument of global warming. They are important for understanding things and predictive quality”

    A lot of the models that are tracking reality pretty well are being attacked because of minute errors. This of course is silly as the models are generally correct and indicative and therefore a good way to indicate or predict probability in relation to human caused global warming. Minute errors are corrected as discovered and do not detract from the overall picture as modeling and measuring improves.

    What I am saying is that it is pretty easy for some to get caught up in the minutia and maybe that is a reflection of individual thought process or bias of some nature, but that generally, it’s getting warmer and that is affecting the weather.

    More heat translates to more moisture in the air so more rainfall, more snow (melting faster though) likely larger climate momentums causing droughts and floods as well as debilitating storms and crop failures.

    This is all just common sense. The world is already experiencing these effects. It’s not like we need a model to see what is happening. Good models help us see what is coming and models are getting better all the time because lots more people are working on it.

    Comment by John P. Reisman — 21 Aug 2007 @ 12:20 PM

  42. Paul, you asked for examples of climate tipping points.

    Your library should have this book:
    http://www.powells.com/review/2007_06_09.html

    If you don’t read the book, at least read the review.

    Comment by Hank Roberts — 21 Aug 2007 @ 12:42 PM

  43. # 9
    I would like to thank Daniel for pointing out “Scientific Reticence and Sea-Level Rise”. I had not seen it.

    Comment by Aaron Lewis — 21 Aug 2007 @ 12:44 PM

  44. Daniel C. Goodwin wrote: “Nobody wants to be accused of being a doomsayer”

    I don’t mind being accused of being a doomsayer. So I’ll say it:

    1. My take on the science is that the warming from the CO2 that humanity has already added to the atmosphere is probably more than sufficient to trigger multiple positive-feedback “tipping points” that will further increase and accelerate the direct anthropogenic warming — and we are already seeing evidence of these feedbacks kicking in; and

    2. Anthropogenic CO2 emissions are presently increasing every year at an accelerating rate, and it is extremely unlikely that humanity will collectively do what is necessary to not only stop that growth in CO2 emissions, but reverse it, and then reduce emissions by 80 percent or more within 5 to 10 years, which is what mainstream climate scientists say is needed to avoid the worst outcomes of anthropogenic global warming. (And per point 1 above, they are probably mistaken to believe that we have that much time anyway.) So,

    3. The rapid, accelerating and extreme anthropogenic warming of the Earth, reinforced by feedbacks, will not only cause the various “disaster scenarios” that will be catastrophic for human civilization (e.g. megadroughts that will wipe out most agriculture, loss of fresh water supplies for billions of people, inundation of heavily populated coastal zones including most of the world’s major cities) but will lead to a global ecological meltdown — a general biospheric collapse — and the mass extinction of most life on Earth.

    So, we are, in a word, doomed. There, I said it.

    Comment by SecularAnimist — 21 Aug 2007 @ 12:52 PM

  45. Daniel, I dont think the Amber Waves comment is an error of judgement, It is a genuine image of how good ot could be if only we did what we know we shuld. If someone (like a president) took that vision to the nation it may work, but I wouldnt hang up my umbrella yet.

    Comment by Nigel Williams — 21 Aug 2007 @ 12:54 PM

  46. [[They (computer models-RO) are important for understanding things and predictive quality but it’s getting warm outside. Everyone feels it. Everyone says hey this weather seems quite different than when I was young.]]

    There are really two other *scientific* ways to predict future global warming trends beside computer models.

    1) Physics.

    2) Paleoclimatology

    I would be really careful on saying that people can observe GW so it must be happening. Remember certain parts of the Earth have been getting cooler…and this is expected….but the average surface temps are going up taken from 10s of thousands of locations world-wide.

    I don’t mean to knock your comments down…but they are simply unscientific. They would not pass for a second in science peer-review journal.

    Comment by Richard Ordway — 21 Aug 2007 @ 1:01 PM

  47. Re #24

    Hi Dean, here’s some more from NASA on the matter:

    Take Warm Water, Stir:

    Sea surface temperatures must be 82 degrees Fahrenheit (F) or warmer for tropical cyclone formation and sustenance.

    http://www.nasa.gov/vision/earth/environment/HURRICANE_RECIPE.html

    Comment by John P. Reisman — 21 Aug 2007 @ 1:03 PM

  48. Re # 37 Daniel C. Goodwin: “Compounding the clumsiness of this obviously inadequate suggestion, the paper concludes on a puzzling footnote, with a whiff of cloying, desperate patriotism…”

    They also appear to be mimicking the concluding statement of the famous Watson and Crick DNA double helix paper (Nature, 1953): “It has not escaped our notice that the specific mechanism we have postulated…” (http://www.nature.com/nature/dna50/archive.html)

    Comment by Chuck Booth — 21 Aug 2007 @ 1:16 PM

  49. re #13

    Hi Bill, just a small note on the IPCC. It is a very large process and typically lags the leading edge of new data and modeling in order to process the large scope of data collected. It’s also in Switzerland and its a fairly conservative place. I know because ‘m over there a lot these days.

    The IPCC will lag but lay down arguments that will be harder to argue with. In my opinion, that is helpful because it keeps furthering the leading edge of the research and giving basis for those new arguments, models, predictions and projections.

    When you add the IPCC data with the leading edge, one can see the trends and potentials fairly well. Using both in our considerations I believe will help us formulate policy and reasonable perspective faster.

    Comment by John P. Reisman — 21 Aug 2007 @ 1:40 PM

  50. I’m no expert in these things, but it seems to me that when you rain on a desert you get mud, not a ‘breadbasket’. You still have no soil and no vegetation or animal life to spawn growth.

    Of course those things would develop over time through some processes about which others probably know a great deal. What I do suspect is that we are talking about a very long time; generations, certainly.

    As for those areas which suddenly get no rain, their long-term future will be even less certain, with this exception: those who relied upon the fertility of that habitat will be forced to relocate.

    To the mud flats, perhaps?

    Comment by Walt Bennett — 21 Aug 2007 @ 1:58 PM

  51. #8 Neil B.

    Be sure that any GW/AGW skeptics that push the “return to equilibrium” argument realize that it may not be (probably will not be?) the same equilibrium.

    In a number of discussions I have had the term “equilibrium” is treated as it were an unchanging absolute state of a system. There are many equilibria and some may not be much fun for human existence.

    #22 Alistair McDonald

    Your meteorology is not on a sound scientific basis. Yes you can calculate the decrease of density of the lower atmosphere because of an increase in water vapor. However your statement implicitly assumes it will all stay near where it is evaporated, much will be advected (transported quasi-horizontally) away.

    But a greater flaw in your argument is that the static stability of the atmosphere will be fundamentally changed by an expected increase in water vapor.

    To a high degree of accuracy much of the atmosphere is in hydrostatic balannce – the downward gravitational force balances the upward-directed vertical pressure gradient. To get air to rise there must be a mechanism to upset this balance.

    An increase of water vapor cannot do this (and create spontaneous upward motion as you imply) because the water vapor fraction of air is constrained by the amount of kinetic energy available to do the work of evaporation.

    With an Arctic Ocean air/sea interface temperature of 0C the maximum amount of water vapor in the lower atmosphere at equilibrium (i.e. saturation), measured as the partial pressure of total atmospheric pressure would be less than 1% of total atmospheric pressure. At 30C, a tempeature no one expects even in an ice-free Arctic Ocean with a runaway greehouse warming scenario, the fraction of total atmospheric pressure at equilibrium is around 3%. Though the value triples the maximum of 3% is a value much too small to overcome the larger magnitude hydrostatic balance.

    So an increase of water vapor because of increased evaporation created by GW/AGW “will not a tipping point make” by upsetting the hydrostatic balance.

    The greater influence of water vapor increases will be once air is lifted, condensation has occurred and rainfall becomes more plentiful.

    Steve Horstmeyer

    Comment by Steve Horstmeyer — 21 Aug 2007 @ 2:10 PM

  52. Who were the referees that peer reviewed the cited article in the Economist?

    Comment by W F Lenihan — 21 Aug 2007 @ 2:21 PM

  53. Re the Schwartz article: I’m not technically qualified to critique something like this, and there’s very little point in my putting the effort into becoming qualified in that way, but let me describe how I lok at these things (for the benefit of Doug Lowthian in particular): Read the abstract, read the introduction, read the conclusion, and then skim the contents. The purpose of doing this is to not only understnad the basic thrust of the paper but to turn up the caveats, which will indicate how much weight the author thinks ought to be put on the paper.

    In the case of this paper, the next to last paragraph tells the tale: It’s a thought experiment using a simple model that Schwartz does not expect will be correct, although he believes that the approach he takes may have some value. The denialists, it seems, never look for the caveats.

    Comment by Steve Bloom — 21 Aug 2007 @ 3:05 PM

  54. “If you evenly sample X, or evenly sample 1/X (or any other function of X) you will get a different distribution of results.”

    Absolutely true, fits are forced to the end of decay components as data is normally taken on a timebase so you have very few data pints at the beginning, where change is the greatest, and very few at the end, where change is the smallest. There are ways around it. Typically, fits are done by comparing the data set to a model, and fit to get the smallest sum of squares Sum of (model-real)^2.
    However, you can multiply the squares at time = t, with an exponential function so that the amount of information is reflected in the fit.
    This is only a rough and ready solution, but it is possible to get good fits in enzyme kinetics using this methodology (using the M-M equation instead of an exponential).
    Indeed, what should be fitted is the “information” in the system, but you need to do the fit before you know where the information is.
    There is a lot of work in this area in information theory, but to be honest, I really do not understand it.

    Comment by DocMartyn — 21 Aug 2007 @ 3:07 PM

  55. Re 24 Dean: “What is the source for more Cat 5 hurricanes? the Hurricane center has denied any such claim and frankly, they’d know.”

    Georgia Institute of Technology and the National Center for Atmospheric Research for starters: http://www.gatech.edu/news-room/release.php?id=654

    Comment by Jim Eager — 21 Aug 2007 @ 3:12 PM

  56. On Bayesian priors and probability distribution generation: doesn’t the work of Forest et al. (GRL 2006) and Webster et al. (Climatic Change 2003) address some of these issues? In the former paper input distributions are not generated arbitrarily but rather derived from historical data, and in the latter these distributions are used to generated pdfs of future climate in a consistent fashion. Of course, these generated pdfs don’t address issues like the probability of poorly understood tipping points, but they are certainly a step up from using climateprediction.net or model ensembles to define pdfs (note that I think that both model ensembles and the .net experiment are very useful, just not for pdf definition). (Disclaimer: I work with the authors I’m citing)

    [Response: Indeed. The problem discussed in the Economist is not related to the use of priors per se, but to the assumption that an appropriate choice of priors allows you to sample model parameter space in a probabilistic way. Mind you, some of the discussion on the influence of priors in the Forest et al papers is a little overblown, since their importance reduces every time you add in new information (as Annan and Hargreaves 2006 showed). I too agree that the CPDN ensembles are interesting though. - gavin]

    Comment by Marcus — 21 Aug 2007 @ 3:14 PM

  57. gavin, stupid question time.

    I know somewhere here abouts you have explained “climate sensitivity ” Could you give a quick
    definition. And then an explaination of how one estimates the varience of the metric

    [Response: http://www.realclimate.org/index.php/archives/2006/03/climate-sensitivity-plus-a-change/ - gavin]

    Comment by steven mosher — 21 Aug 2007 @ 3:22 PM

  58. RE #39 & #35, and “the Venus effect.”

    Well, a lot of people have trouble understanding analogies (and poetry, for that matter). But then again many people don’t have such trouble. I would guess most people grasp them. That’s why they’re in such heavy use.

    Comment by Lynn Vincentnathan — 21 Aug 2007 @ 4:08 PM

  59. re: #52 & The Economist
    The Economist is not a peer-reviewed scientific journal.

    However, from multiple firsthand experiences, IF you send a pleasant note (which doesn’t have to be intended as a letter to editor to be printed) to them that basically says:
    1) “This is in error, facts…”

    2) “OK article, but you need to know about XXX, see URL, a good source on this topic.”

    THEN

    a) Sometimes later articles show they go do more homework.
    b) Sometimes you even get a person-generated email in reply.
    c) and some.times they even invite you to stop by next time you’re in London.

    I already took action 2) on this topic yesterday.

    Comment by John Mashey — 21 Aug 2007 @ 4:21 PM

  60. Re message 48 where Chuck Booth points out the playful allusion to Watson and Crick’s

    It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material.

    What fun! Patriotism is dangerous medicine to fiddle about with, however, particularly in the current atmosphere where the percentage of American exceptionalism is increasing in toxicity, when calculations more fully account for biogeophysical feedbacks.

    Comment by Daniel C. Goodwin — 21 Aug 2007 @ 4:44 PM

  61. Re #38

    Ref. #41

    —–
    Re #46

    Dear Richard,

    I agree with you. It is an unscientific assessment. But I travel around the world quite a bit and I am hearing this type of comment more and more. I did not wish to infer that it was scientific assessment, merely an observation that has a modicum of relevance to the discussion.

    Besides the certain places that are getting cooler are fewer than the places that are getting warmer :)

    Beyond that, the physical evidence in the melting of the glaciers is pretty much the smoking gun. Combine that with the observed increase in SST and stronger storms, et cetera…

    By the way, I am not submitting the comments for peer review.

    Thanks for the input,

    Comment by John P. Reisman — 21 Aug 2007 @ 4:48 PM

  62. Eric (skeptic) says: “What they forget is there are negative feedbacks elsewhere, particularly in the weather in a wetter world. Tim pointed one out in the Sahara.”

    I think you’re entirely missing the point – there is significant uncertainty in the regional predictions, and much less uncertainty in the global predictions. Look at the observations and forget about the models for a second:
    http://www.sciencemag.org/cgi/content/abstract/312/5777/1179

    There, they look at the tropospheric and stratospheric temperature trends for 1979-2005 and find that there is a poleward shift of the tropospheric jet streams and their associated subtropical dry zones.

    Other measurements show the increasing trends in Indian, Atlantic and Pacific seas-surface temperatures. The notion that higher sea-surface temps means more evaporation means more precipitation over Africa is just too simplistic.

    As yet another contributing factor, the deforestation in West Africa means less evapotranspiration over land surfaces and a possible related decrease in precipitation.

    Any honest person would include all these factors – the anthropogenic CO2 forcing, the intrinsic natural climate variability, and the effects of deforestation. What the denialists are doing is just picking those factors that support the notion of ‘beneficial natural global warming uninfluenced by humans’ and ignoring all the others.

    If you really want to understand what’s going on, you can’t leave anything out. If you want to promote a certain position, than you only include evidence that supports that position – which is the difference between scientific work and public relations work.

    Note – people are just now starting to come up with physical models that explain the formation of jets in the atmosphere. One concept here is ‘jumping jets’ – a possible example of a planetary-scale transition or tipping point. It refers to the tendency of some jets to reposition themselves (and their associated climates) suddenly when the climate forcing reaches some threshold level. The change in jet stream positions over the US and the Atlantic during El Nino / La Nina is an example of this phenomenon. This helps explain the apparent contradiction between high sea surface temperatures and expanding dry regions. The drying American Southwest is another example of this effect.

    Comment by Ike Solem — 21 Aug 2007 @ 5:05 PM

  63. Re 30: “His work depends on (among other things) the assumption that there’s only *one* characteristic timescale for global climate. Physically this would seem to be impossible; each component of the climate system (atmosphere, ocean, cryosphere) will necessarily have a different characteristic timescale.”

    You’re understating the wrongness of Schwarz’s assumption, Tamino. Each of these components on the climate system has a whole range of time scales. Specifically the ocean (which is the component that is most relevant here) has a time scale for absorbing heat in its top metre or so, a longer time scale for mixing this heat down to the maximum seasonal mixed layer depth, a longer time scale again for subducting heat into the permanent thermocline and a very long time scale for warming up the whole thing. Thus between 1961 and 2003, global average SSTs increased by about 0.45 degC (AR4 WG1 Fig 3.4a), the average temperature of the layer to 700 m increased by about 0.1 degC (AR4 WG1 chap5 Sec 5.2.2.1 & Exec Summary) and the average temperature of the entire ocean increased by 0.037 degC (AR4 WG1 chap5 Sec 5.2.2.1).

    Sorry this is a bit off-topic :-)

    Comment by Mark Hadfield — 21 Aug 2007 @ 5:07 PM

  64. I understand that permafrost thawing has sometimes been presented as a “tipping point”, even though it’s one of several contributing feedbacks. But the question is whether we have a good idea of the maximum likely carbon release (both existing methane and organics decay). With significant outgassing, perhaps it could become a stronger feedback despite being “globally well-mixed”? Along with oceanic methane spurts and other effects, we presumably still have the possibility of acceleration events tipping other elements in the system. Since we can’t determine how everything will play out, this is all quite an experiment.

    Comment by Alex N — 21 Aug 2007 @ 5:53 PM

  65. Ike (#62), it’s a very good point to take into account all evidence. I believe Alistair (#22) does not. There are many potential warming and cooling effects as Steve (#51) points out. They all have to be taken into account and that’s when the tipping point tends to disappear. I agree with Ike, Nick (#23), Ray (#26), and Lawrence (#29) that the effects of the local tipping points will be global in many cases and difficult for life. But that does not make them global tipping points, just global effects. In a world with lots of local tipping points the global balance will certainly start to be affected, plus the effects may be messy enough that nobody will care what the global average is anymore. But the negative feedbacks, negative tipping points and numerous positive global side effects will be just as real.

    Comment by Eric (skeptic) — 21 Aug 2007 @ 6:07 PM

  66. Re #11: “The problem is genetic. The average human is just not good enough in math to survive the next 200 years.” Not true.

    While we’re discussing Bayes Theorem and other areas of probability and statistics, others
    out there are working on developing and improving alternatives to fossil fuels, such as fuel cells, solar panels, wind turbines, plug in hybrids and the like. Models are important much as Paul Revere was important in telling us what’s coming. The next step is to react. People in other developed countries have already made important changes.
    See http://ec.europa.eu/energy/index_en.html.

    Here in the U.S., we’re coming around to realize that energy efficiency is critical and that conservation is not just a “personal virtue” in the words of a very influential political figure. A penny saved is a lot more than a penny earned,especially when environmental effects are considered. You don’t have to look much farther than the record profits of oil companies and oil exploration companies in the past few years to see the cynicism in those words.
    We don’t need to know tensor calculus or matrix or probabitiy theory to put a halt to what’s becoming more and more obvious with each passing year.

    Comment by Lawrence Brown — 21 Aug 2007 @ 6:29 PM

  67. The way to handle the problem of parameterzation dependence of sampled estimates in statistics is pretty much along the same lines as Jeffreys’ prior; oddly enough Harold Jeffreys was a geophysicist.

    Comment by Andrew — 21 Aug 2007 @ 8:04 PM

  68. If you evenly sample X, or evenly sample 1/X (or any other function of X) you will get a different distribution of results. Then instead of (in one case) getting 10% of models runs to show behaviour X, now maybe 30% of models will. And all this is completely independent of any change to the physics.

    The point of the butterfly effect in chaotic systems is that the resulting probability distribution IS independent of the distribution with which you started. Provided that you allow enough time to elapse in the model, the results from neighboring samples will be entirely independent. Both you and the Economist appear to be assuming that model output will vary smoothly with the input parameters, which is generally not the case for chaotic systems.

    It is important not to confuse the probabilites that something will happen in a model with the probability that it will happen in real life. When X% of the ensamble elements of a model predict that something that means that that is the chance that it would happen providing that the initial starting condition is correct, that the model accurately captures the physics, and so forth. The chance that it will actually happen in real life must take into account these errors as well, which is sufficiently complicated that estimates of real life chances are not usually published.

    Comment by Blaine — 21 Aug 2007 @ 10:04 PM

  69. I guess I don’t understand something at the end of this article. If the probability of any particular path in the simulation is not proportional to the probability of this path actually occurring, then why is it valid to average the ensemble of paths and claim that the average value of the (say) temperature increase is the same as the likely value of the actual temperature increase? What does the distribution of paths actually mean?

    [Response: Fair point. The reason why the multi-model mean is used is because it empirically shown that it works the best at getting other observables correct. That implies that at least some of the errors are random and not systematic. But it doesn't imply that there are no systematic errors remaining. - gavin]

    Comment by Mitch Golden — 21 Aug 2007 @ 11:07 PM

  70. Eric (skeptic): Seems like the “numerous” positive (“global”?) side-effects discussed by “skeptics” are often rather dubious or leave out caveats, and don’t appear to outweigh the negatives associated with the situation getting out of hand. And I’ve yet to see any successfully reviewed study suggesting negative feedbacks or “negative tipping points”(?) are strong enough to prevent that from happening. Seems that on timescales important to humanity, amplifying feedbacks are likely to rule.

    Comment by Alex N — 22 Aug 2007 @ 12:10 AM

  71. I don’t know, I am only an old, near retiring age, bumbling general practitioner. I have no more qualifications to discuss AGW, tipping points or GIS melting than the next person, though I have studied these issues extensively on this site and others, I have John Houghton’s book, even read Fred Pearce’s book in 1989, but regrettably put that information in the back of my mind for the next decade. But having said that, I think my age, and my experience of life, and in particular, my experience of other people’s lives, and the normal course of physiology and the abnormal course of pathology, has gained me some insight into the how living systems do function and how they go wrong. Although James Lovelock doesn’t possess a clinical medical degree, he has worked in many medical fields and has a PhD in medicine. He certainly knows his physiology, and has applied that breadth of view in his theories about Gaia. I would suggest that this view point is of inestimable value when examining complicated issues like AGW.

    My comments both about tipping points and Bayesian projections, and so much about AGW would be the same. I think we need, like a good physician, at the times you have something wrong with you and you don’t quite know what’s going on, to stand back a bit and look at the whole organism and the totality of its functioning. If the world was my patient, I would be very apprehensive about the prognosis, and the patient should be justifiably frightened.

    For instance, take the comments about tipping points, are they local, are they global? This is not the issue. The loss of the Indian monsoon might not affect me here in New Zealand, but there are a billion people on the planet that it would. The loss of ice in the Arctic, (and this year surely brings us to the realisation that the tipping point in the Arctic is almost upon us – what chance no summer ice within ten years, or five years?) again might be remote to me, but to the Inuit and to those living in northern climes in Europe, who number many millions, it could be very troublesome. Increasing heat and dryness in the south-western USA would again adversely affect tens of millions directly and in the “breadbaskets” of the world, affect hundreds of millions in their food supplies. One thing we must understand is that the whole planet is local, we are all co-dependent on one small globe whizzing through the ether. We are several orders of magnitude larger than Easter Island, but we are just as isolated and just as vulnerable. I very much doubt there is such a thing as a “local” or “regional” tipping point. We are all in this together and too many such arguments seems to me the sort of thing that Rana temporia might have croaked on about in the heating pan of water.

    Similar also are my comments on Bayesian predictions. This is all so esoteric, and seems almost to come down to the same sort of arguments that once exercised the best brains in Christendom as to how many angels can dance on the head of a pin.

    So let’s stand back, and things become so much clearer.

    There is, as far as we know, only one planet in the universe that can support life, and it is the one that supports us, and if something goes wrong with this planet, we cannot escape anywhere else.

    We are called Homo sapiens sapiens, which supposedly should mean that we have the intelligence, properly directed, to deal with the sort of problem that besets us.

    We have now almost all of us accepted the reality of AGW.

    We are ourselves the direct cause of these problems. We know the world’s climate can change due to other factors not involving human agency, but for the moment, the threat of the heating world arises from our own actions.

    It is, even with present technology and the power of many thousands of expert people’s minds, impossible to precisely predict the future but whatever the future, it is definitely going to be very different from today, perhaps as different as the ice-age planet was ten thousand years ago. We haven’t yet reached a one degree C rise in global temperature, but this year brings warning of the complete loss of arctic summer ice and the imminent collapse of the normal arctic climate. If less than one degree can do this, what will 2 degrees or even more accomplish?

    Humanity has thrived in its present environment, which includes a relatively constant climate in the Holocene, hardly varying at all for ten thousand years. Humanity has come to occupy every ecological and climatic niche over this time. It is almost certain, because we have prospered in a relatively constant climate, that any change in that climate will bring many more problems than benefits. All our infrastructure, our housing, where we live, whether by rivers, lakes or coasts, our water supplies, our farms and farming practices, our industry, our fishing, our forests, are adapted to those niches and, almost by definition, any change in prevailing climatic conditions will mean that this infrastructure will not be best suited for the new climate.

    We are now so numerous, and have already occupied all the most favourable areas of the Earth’s surface, that we won’t be able to move to avoid these climate difficulties, but will have to adapt our present investment and infrastructure to cope. The expense and the difficulty of this obviously is going to be massive, and has the capacity to severely reduce our wealth. It is likely that there will be some areas that this will in fact be impossible, e.g., the Ganges delta, Florida, flood plains, dry areas dependent on aquifers or glacial water feeds etc. It is likely that many areas, already full to the brim with humanity, will need to cope with tens of millions of climate refugees. Imagine New Orleans magnified a hundred-fold or more, even in a best-case scenario. .

    We talk about 2 deg C of warming with some equanimity, as if this is not really going to be an issue, and of course we are already committed to at least 1.5 deg C of warming. Yet even this amount of warming could prove quite disastrous to some areas of the world, and there may be major climatic changes that we haven’t even envisaged. It is likely that the melting of the summer ice in the Arctic will be the first example of major climate change to cope with. Will the jet stream move south, north or stay where it is? Will increasing atmospheric moisture cause major increases in summer rainfall in northern latitudes, including North America and most of Europe. Will the floods the UK has seen this year become the norm and how could we cope if it did? We shall shortly find out.

    Is anything that I have written under any serious dispute? Yet this last few weeks have seen Russia planting small flags on the Arctic Ocean floor, Denmark asserting territorial claims off the Greenland coast, and Canada promising to station hundreds of soldiers in its Arctic Territories, all with the object of securing sovereignty over the possible resources of the Arctic. These resources include of course, oil and gas; the Arctic is one un-explored region where large amounts of such fossil fuels could be found.

    There is some sort of supreme cosmic joke here, though I don’t find it particularly humorous. That humanity should so poison our atmosphere as to permanently damage one of the Earth’s major climatic control mechanisms, then take advantage of this damage to damage our climate even more, is just so absurd, so stupid, so cosmically cretinous, as to beggar belief. It is the positive feedback mechanism to beat them all.

    And yet, looked at from our present perspectives, it is hardly surprising. The vast majority of humanity hasn’t even noticed or commented. Here in New Zealand we are proposing to spend over a billion dollars in oil and gas exploration in the oceans to our south. Our commitment to continued economic expansion is almost total, and even threats to the health of our planet doesn’t cause us to waver in this.

    I think we solve this quandary by looking at AGW in an entirely different way. To go back to my introduction, when I introduced myself as a physician, standing back, and taking the overview, not only has the physician a professional obligation to you and your welfare, and your family and children, but he has a moral obligation, which actually transcends this professional obligation. Furthermore, and this is the important point, this moral obligation is in fact no different in kind or degree to the moral obligations that we all have to each other in any case. It would be my contention that AGW is, as much as anything, a moral issue, the supreme moral issue of our times. Our moral obligation to our planet arises from our moral obligation to each other. Whilst we can certainly examine AGW from a scientific, political, economic, environmental or societal viewpoint, I don’t think we are going to get very far until we admit this moral perspective.

    And this is why I believe that we should be looking at the morality of what we are doing. It brings everything back into focus. We continue to make the most appalling errors by treating this issue as one of pure logic. It would be nice to think that humanity could be guided by logic but, generally, this doesn’t happen. It is not logical to damage our planet any further, but it is not entirely illogical to try and sustain our present standard of living either, it has brought humanity many undoubted benefits. But by simplifying all these discussions and arguments to a simple moral perspective we avoid these pointless and irresolvable arguments. What we are doing to the planet and ourselves is immoral, here are some reasons why.

    It is immoral to be fouling our own nest.
    It is immoral to fail to take action to deal with global warming.
    It is immoral to undertake actions that will make global warming worse.
    It is immoral not to care for others as we would wish to be cared for ourselves.
    It is immoral for rich nations to cause damage to poor ones who are not responsible.
    It is immoral not to care for our children.
    It is immoral not to care for their children
    It is immoral not to care for the planet that sustains us.
    It is immoral to diminish the lives of others for our own benefit.
    It is immoral to require others to deal with problems that we have created.
    It is immoral to try to get others to ignore the problem.
    It is immoral to care more for our present wealth than any of these other things.

    I could go on, I often do. But I will end with observing that there is now something distinctly Darwinian in what we are doing – in fact I think Darwin would have a good chuckle at our expense, if, as a humane man, he wasn’t weeping. We are the universe’s first species, as far as we know, intelligent enough to have discovered the theory of evolution, the principle of natural selection and survival of the fittest. What is now so ironic is that we seem determined also to be the universe’s first species to deliberately set out to prove it.

    Comment by John Monro — 22 Aug 2007 @ 12:46 AM

  72. I know this is off topic, however Philip Stott wrote a letter into the Telegraph today which included this line:

    ‘First, new research indicates that our climate may be only one third as sensitive to C02 as has been assumed.’

    What research is he talking about??

    link to the letter – http://www.telegraph.co.uk/opinion/main.jhtml?xml=/opinion/2007/08/21/nosplit/dt2101.xml

    thanks

    Comment by Dominic — 22 Aug 2007 @ 3:05 AM

  73. So the distribution of model results isnt a pdf of the climate system.

    Then what does it tell us?

    Should values, like the 11 degrees simulated by climateprediction.net, be considered ‘possible’?

    Or is even the range meaningless?

    [Response: Personally, I don't consider 11 deg C possible. It's interesting to see that a model can generate something like that, but whether it matches with the real world is key. Many of the subsequent analyses of the CPDN runs show that even modest requirements of TOA radiation balance for instance, none of the high end numbers survive the cut. - gavin]

    Comment by Ed — 22 Aug 2007 @ 5:32 AM

  74. “The way to handle the problem of parameterzation dependence of sampled estimates in statistics is pretty much along the same lines as Jeffreys’ prior; oddly enough Harold Jeffreys was a geophysicist.”

    The problem is how to find the Jeffrey’s prior when the likelihood function isnt available analytically as a function of the parameters.

    Comment by Ed — 22 Aug 2007 @ 6:10 AM

  75. [[The really odd thing, for me, is that mathematically, the data themselves contradict his hypothesis of a single timescale for climate response. I believe I can show, beyond doubt, that the data he presents *reject* the idea of such a simple behavior, but Schwartz presents an argument (which I regard as invalid) that they confirm it.

    I’m considering writing it up for JGR, and also considering doing a blog post on the subject.]]

    I wish you would do the former (the latter would also be good). I’d love to see a paper in JGR from a regular poster here (other than the professional climatologists, that is).

    Comment by Barton Paul Levenson — 22 Aug 2007 @ 6:34 AM

  76. [[http://personals.galaxyinternet.net/tunga/DefectiveGlobalWarming.pdf

    “Why is the albedo of Venus important? When the albedo is at 0.80, the Global Warming Theory falls apart. . .]]

    I looked at your reference. I’ve never seen a clearer example of pseudoscience. The paper starts getting things wrong right at the start, by saying global warming theory was invented “a few decades ago” — try 1896. It then goes on to say that airborne carbon dioxide “reflects thermal energy” — no it doesn’t, it absorbs it. And so on and so on. The author of your reference is a crackpot, clear and simple.

    Comment by Barton Paul Levenson — 22 Aug 2007 @ 6:39 AM

  77. Re: #71

    John,

    Very interesting post, well stated. I approach the problem slightly differently. The problem with the morality argument is that there are those who will argue the immorality of needlessly disrupting societies and economies to chase a ‘solution’ to a ‘non-existent problem’, or to a problem about which not enough is known to wisely choose a credible solution. There is a point to be made there.

    The problem with the Darwinian argument is that many people do ‘get it’. Those who argue in favor of a BAU approach are not necessarily oblivious to the self-detructiveness of that stance; they simply understand that it will be others, not themselves, who will face those consequences. At its base, this approach can be defended as practical and rational, at least as far as it serves the near-term interests of those who hold it.

    My approach is this: man has greatly accelerated his ability to alter his environment (Gore’s “bigger shovel” example in AIT). Man has not necessarily accelerated his ability to understand the consequences of these alterations. To some extent this blindness is useful, because we don’t know enough about future conditions and capabilities to choose too far in advance.

    AGW is clearly a new paradigm. Each of us contributes the tiniest increments to the overall problem, but the comnbined, sustained contribution is a real problem. We don’t feel that, though: it’s a mighty chilly August here in Pennsylvania, for example. We don’t see it: CO2 is invisible and mostly odorless. We can’t always take specific measures to reduce our contribution, and when we do, we don’t always understand the consequences of THOSE choices.

    Complex stuff.

    Much too soon to judge our ability to learn from this experience. We are still in the bubbling cauldron of competing ideas.

    I do not necessarily disagree with your views vis-a-vis morality and Darwinism, but I do not believe they are the root issues which confront us. I believe that the root issue is simply, man learning how to sort through myriad sources of information in order to make perceptive judgements. It’s almost impossible to imagine this process as something that can be done with any degree of rapidity, or as something with any sort of definable end-point.

    Comment by Walt Bennett — 22 Aug 2007 @ 9:51 AM

  78. re Dominic #72
    Just to avoid any confusion, the Stott who wrote to the Telegraph is not the same person as Peter Stott, the climatologist at the Hadley Centre, who wrote the recent paper linking changing patterns of rainfall to Global Warming.

    (I am also not the same person as # 70!)

    Comment by Alex Nichols — 22 Aug 2007 @ 10:01 AM

  79. RE 57.

    Thanks Gavin.

    Comment by steven mosher — 22 Aug 2007 @ 10:02 AM

  80. RE # 45

    Nigel, you said, [I dont think the Amber Waves comment is an error of judgement, It is a genuine image of how good ot could be if only we did what we know we shuld.]

    The American diet relies upon that Amber grain (and the amber lager we love so well)and exports the surplus stock of those Amber Waves of grain.

    Here is where I disagree with Dr. Hansen and all the ethanol advocates.

    It is self-destructive to use the global grain basket to fuel our vacation trip to the beach. And, the ethanol industry is betting the farm on predictable climate conditions during the growing season in a world of record Arctic sea ice meltback and its conseguences for Western North American temp and precip.

    Comment by John L. McCormick — 22 Aug 2007 @ 10:44 AM

  81. Re John L. McCormick in post 80

    I doubt that McCormick’s characterization of Hansen as an “ethanol advocate” is accurate, though I can understand how the footnote I quoted might lead one to that impression.

    Regarding not what Hansen personally advocates anyhow, but what Hansen et al advocate in “Climate Change and Trace Gases:” their conclusion is: (1) That some means must be found to draw down atmospheric co2 concentrations. (2) If emissions from combustion of biofuels are sequestered (and sequestering looks like a tractable engineering problem), the result of such activity on a large scale would be to draw down atmospheric co2.

    There are many interesting things about this proposal. One of them is that, where co2 extraction technologies are concerned, Hansen et al found none more efficient or promising than those which life has already developed: photosynthesis and respiration. Another interesting thing is this proposal’s implicit blithe dismissal of problems like the price of tortillas in Mexico.

    Please remember, the point here isn’t “look how full of crap Hansen is,” the point is that even the most thoughtful people around (Hansen, for his courage through the decades, really is a personal hero of mine) make some intellectual blunders occasionally. I’ve even been known to stumble myself, believe it or don’t.

    Comment by Daniel C. Goodwin — 22 Aug 2007 @ 12:04 PM

  82. RE # 81, Daniel, I share your respect for, and appreciation of, Dr. Hansen and his contribution to our understanding AGW.

    Comment by John L. McCormick — 22 Aug 2007 @ 12:40 PM

  83. Re 71- I fully agree with this posting by John Monro.

    I would add a growing concern that the stance of some denialists may include a hidden agenda. That agenda is basically this: “When things really begin to hit the fan and hundreds of millions or billions are in great distress, we will have to be strong enough to fend them off and let them die. Otherwise, they will overwhelm us and we will all go down together. So we have to push for continuing development and ward off any any action that might compromise our hegemonic position, even if that means accelerating the crisis.”

    A note to denialists – I know this does not represent most of you, but please take care that this sort of idea does not creep into your thinking.

    Comment by Ron Taylor — 22 Aug 2007 @ 1:03 PM

  84. RE the “reticent scientists” thread (#7, 9, 19, 37, 44), I did my thesis on “Environmental Victimology,” and came to realize there are several perspectives:

    (1) THE NAYSAYERS (often industrialists), who would prefer not to accept that a problem is happening, and would require more than 95% confidence it is (99, or even 101% :) ).

    (2) THE SCIENTIFIC MODEL: Scientists usually require 95% or greater confidence to make a claim. They need to protect their reputations, so that people will go on believing them — so making false claims (alpha error) is much worst for them as professionals, than failing to make true claims (beta error). They cannot be the boy crying wolf. If they are, they get cut out of the loop.

    (3) THE MEDICAL MODEL: Victims and potential victims of environmental harm, and environmentalists, and the general public (you’d think), would like to avoid environmental harm in the first place. They would be reticent to continue a practice that MIGHT be harmful to them or others. They would be greatly averse to failing to avoid a true harm (beta error). As are doctors and their patients when viewing test results — the doctor will not tell his patient he/she is are only 94% confident the lump is cancerous, so they won’t operate, and to come back next year to see if it’s made the 95% confidence interval.

    So it’s usually potential/actual victims, environmentalists, and the public who are well in front of the false-claim-avoiding, reticent scientists in clammering for ameliorative action.

    But this time it’s different (as scientists have themselves pointed out…and are scratching their head over); the scientists are the ones out in front clammering, while the public switches the dial to some entertainment channel.

    I’ve been thinking for over 17 years (since I became active on the GW issue), that we’d reach some societal “tipping point,” and go into a very different state, a revitalization (or social) movement to address this issue (e.g., the 60s anti-war, civil rights, and feminist movements). I’ve been waiting…..

    Of course, there is industry/government/media complex obstructionism, and a social movement’s need for many to perceive future/current harm to themselves, and the issue of GW being a bit slow-moving.

    But now I’m thinking that there are these other socio-cultural-psychological negative feedbacks that are stalling this flip into action. For one thing, it’s a lot easier if there are single, identifiable perpetrators against which to rail. But it is we ourselves who are the perpetrators, though on the whole the greater perps will suffer the least, and the least (or non-perps) will suffer the greatest. The very poor, who are and will be suffering the most, tend to lack social mobilization resources….though the movement might come alive with them — or become a big world clash.

    I’m thinking what this issue of mitigating global warming will take (at least on the part of the higher end perps, like us Americans) is very difficult, introspective work, self-examination, and humility. You’d think religions would be in the forefront, since that’s their province….but some of the greatest resistance I’ve seen is from the “religious,” and it seems religions (in addition to many good things they do) have this dsyfunction of helping people become self-righteous and impervious to acknowledging they might be doing something wrong. The religious do join social movements……against other people’s sins.

    This is a tough nut to crack. But a great opportunity for some deep and true improvement in the (inner and outer) human condition. Like a real conversion to goodness and caring.

    Comment by Lynn Vincentnathan — 22 Aug 2007 @ 1:32 PM

  85. Re: #81

    I have been thinking about the biofuels as sequestration idea for a while (not very deeply I admit!) but here is my noodling.

    Suppose we come up with a scheme like that proposed by some UNH researchers to use green algae in closed tanks to produce biodiesel fuel stock. One could apply this technology in a number of ways.

    One would be to hook it up to municipal waste water systems and have localities produce fuel stock that they could sell to refineries. This would be great for a number of US policy problems like improving balance of trade, removing the funding sources for unstable/repressive/hostile regimes, funding local government (imagine if your city ran at a profit like the State of Alaska) and so on.

    But suppose for a moment that one could make the technology very simple and cheap. Tanks built from discarded plastic beverage bottles, feed stock from seaweed or other local biomass (think tropics where there is much poverty). storage in discarded steel drums or even the bottles themselves, a cottage industry of picking up the produce with circling trucks. This would become (for a while) an easy way to make money and if the technology is simple/viral enough, we get sequestration out of the deal too. Once we have reached break-even on energy generation, we could continue to buy the fixed carbon for sequestration, energy supply buffering (think strategic petroleum reserve) or even maufacturing (plastics). If it gets too out of control, the market will drop the price too low for even poor Indonesian farmers and they will be left with a system that simply makes them self-sufficient in energy.

    Anyway, just an idea.

    Comment by Richard Wesley — 22 Aug 2007 @ 1:36 PM

  86. I’m also thinking there’s probably a difference among different types of scientists. A geologist won’t be losing his/her focus of scientific interest for billions of years, but biologists may be losing their species of scientific focus, and might be more vocal in their speaking out against GW.

    The death of an organism (a person, animal, or plant) is not only a tipping point, but a tipping point of no return (as opposed to climate “hysteresis” (#35), which is more like an extreme fever that eventually goes back down).

    So is extinction of species.

    Comment by Lynn Vincentnathan — 22 Aug 2007 @ 1:44 PM

  87. Re #71 Where Doc Munro ended:

    We are the universe’s first species, as far as we know, intelligent enough to have discovered the theory of evolution, the principle of natural selection and survival of the fittest. What is now so ironic is that we seem determined also to be the universe’s first species to deliberately set out to prove it.

    It is highly unlikely that we are the Universe’s first species, which leads to Enrico Fermi’s Paradox – Where are they? See:
    http://en.wikipedia.org/wiki/Fermi_paradox

    The paradox is easily resolved if we assume that any species that developed intelligence would inevitably be aggressive, since it would have developed through the process of the survival of the fittest. Like us, they too would burn their planet’s fossil fuels as if there was no tomorrow. They too would not only cause the end of their civilisaton, but also the end the prospect of any new civilisation because the natural resources needed to advance beyond the stone age had already been squandered.

    Comment by Alastair McDonald — 22 Aug 2007 @ 2:00 PM

  88. Here’s something re what to expect from 2100 temps — no ice cap (I guess this is another nail in the denialist arguments):

    Study casts doubt on earlier ice cap research

    Source: Copyright 2007, Reuters, see: http://www.climateark.org/shared/reader/welcome.aspx?linkid=82443
    Date: August 22, 2007
    Byline: Michael Kahn

    Pinhead-sized fossils buried deep under the ocean show that glaciers did not coat the poles 41 million years ago, a new study shows, disputing earlier research that suggested huge ice sheets covered the Earth’s extremities.

    Any glaciers then — a time when the planet was much warmer — would only have been in small areas in Antarctica’s interior and not in the Northern hemisphere, said Paul Wilson, from Britain’s National Oceanography Centre, who led the study…..

    Comment by Lynn Vincentnathan — 22 Aug 2007 @ 2:02 PM

  89. Lynn, that’s apparently referring to something now in Nature.

    I followed their link back as far as Reuters.

    http://uk.reuters.com/article/scienceNews/idUKL2286724920070822

    “… In the period his team studied, the earth had about as much carbon dioxide in the atmosphere as scientists predict may be present in 100 years, so the findings also offer clues as to how rising greenhouse gas levels may affect the planet, Wilson said.”

    Comment by Hank Roberts — 22 Aug 2007 @ 2:37 PM

  90. I think the world is naive if they continue to blind themselves towards our environmental issues. It’s time we open our eyes and see all of the symptoms that occur every day. The symptoms for the “tipping point” are happening as we speak.
    Whether or not there is a tipping point, we need to act as if we are drawing near the tipping point. Politicians twiddle their thumbs at the mercy of corporations. We have no time to wait, our world is in a dire state and something needs to get done, now.

    http://www.globalwarminglife.com

    Comment by Heigi Blume — 22 Aug 2007 @ 4:02 PM

  91. Eric says:”But the negative feedbacks, negative tipping points and numerous positive global side effects will be just as real.”

    That statement would be more believable if you were to attempt to give some (any) examples of such “positive global side effects” or “negative tipping points”.

    A number of comments above point to the need to ‘do something’, but let’s just spell it out – we need to end the use of fossil fuels on a global scale, and we need to put an end to deforestation, particularly in the tropics.

    Doing this creates a big problem – what source of energy will humans use in the future? Solar and wind are huge energy sources that are largely untapped. If we start with replacing all fossil fuels used in agriculture with solar / wind power (coupled to efficient energy storage systems, of course), than you can get agriculture off fossil fuels. Once that is done, you can examine the issue of sustainable biofuel production.

    The basic point is that a blend of renewable energy sources will be required. A lot can be learned from traditional energy sources – i.e. synergy matters. For example, you can use solar thermal heating to provide a good deal of the energy needed for ethanol distillation. As many have pointed out, one acre of biofuel crops provides enough fuel to work that field for decades. Put all these energy sources and storage mechanisms together – sunlight, wind, photosynthesis and improved technology – and you have enough energy for all, with no need for nuclear power or coal carbon sequestration.

    If one includes human activity within the ‘Earth system’, then a rapid transition to a renewable economy would be an example of a ‘negative tipping point that counters the projected long-term effects of global warming’.

    Comment by Ike Solem — 22 Aug 2007 @ 5:36 PM

  92. I’m pretty much convinced now that the climate is changing due to CO2 polution.

    I’d like to be pointed a reasonable site discutting prospective :
    – what could be done
    – what will likelly be done (my personnal bet is : too little too late, starting in 10 to 20 years when politicians feel the anger of Joe Sixpack the voter who finally got flooded or desertified)
    – who will loose
    – who will win

    anyone can point to such a site ?

    [Response: Try http://www.climatepolicy.org/ or http://www.cleantechblog.com/ - gavin]

    Comment by Folbec — 22 Aug 2007 @ 6:41 PM

  93. re 83: “a growing concern that the stance of some denialists may include a hidden agenda… ”

    I’m positive this is true, as it is for many proponents of the AGW theory. Might be best to just leave the factions of both camps alone, though I have to admit their cacophony sometimes just can’t be ignored.

    Comment by Rod B — 22 Aug 2007 @ 6:52 PM

  94. Actually there has been a set of environmentalists that for some time now have the survival and enhancement of the human species way way down on the priority list. Granted they’re the fringe, but they’re fun to talk about…

    Comment by Rod B — 22 Aug 2007 @ 7:01 PM

  95. “Politicians twiddle their thumbs at the mercy of corporations. We have no time to wait, our world is in a dire state and something needs to get done, now.
    http://www.globalwarminglife.com
    Comment by Heigi Blume ”

    I have in my hands a photocopy from Science 10 February 1989 pp 771-781. “The Greenhouse Effect: Science and Policy” Stephen H. Schneider.

    “Within the past year (1988) cover stories of both time and Newsweek have featured global warming from the green house effect and ozone depletion from industrial chemicals. The intense heat, forest fires, and drought of the summer of 1988 and the observation that the 1980s are the warmest decade on record have ignited an explosion of media, public, and governmental concern that the long debated global warming has arrived-and prompted some urgent calls for actions to deal with it. For example, the National Energy Policy Act of 1988 to control carbon dioxide emissions was introduced by Senator Wirth in August 1988, and hearing were held on 11 August. At that hearing,, there were sharply conflicting views about whether policy actions are premature given the many remaining scientific uncertainties. Whether some amount of scientific uncertainty is ‘enough’ to justify action or delay it is not a scientific judgment testable by any standard scientific method. Rather, it is a person value choice that depends upon whether one fears more investing present resources as a hedge against potential future change or, alternatively, fears rapid future change descending without some attempt to slow it down or work actively to make adaptation to that change easier.”

    So although the science has improved during the past 18 years, the politicians and corporations haven’t. They and the media are not guilty so much of lying in what they say, they are guilty of lying by NOT saying things to the general public.
    Business as usual.

    I wish our resident skeptics and denialists could see this article and research what is contained in the footnotes. Then they’d begin to understand the science behind climatology and that very little of Realclimate is ‘new’. And that delay of action was ALWAYS the game plan. (And I wish archived issues of Science were available online to non-subscribers.)

    Comment by catman306 — 22 Aug 2007 @ 7:09 PM

  96. Hi Ike, my own small example would be my $32/month electric bill from mid-June to mid-August in hot Virginia (2000 sf house). I am not worried about warming around me, if it happens it will help me save money in the winter with minimal effect in the summer. Planting even more shade trees might be my very minor negative tipping point. I agree with your sentiments though because if we are going to heavily subsidize farmers then we should subsidize them to become sustainable in the long run.

    Comment by Eric (skeptic) — 22 Aug 2007 @ 7:17 PM

  97. Re 84
    People need to feel that damage will occur within their planning horizon before they express any real outrage. (Cite personal experience running an environmental canvassing operation.)

    Now we have rather short planning horizons. Tell people that there will be sea level change in 80 years, and they do not care because it is beyond their planning horizon. They assume that as the seas rise, people will move somewhere else and technical problems will be solved as they arise.

    Tell people that there will be real problems in 5 or 10 years and you will get a response. Better yet, show them that there is a problem NOW! Show people pictures of drowned polar bears and you will get a response NOW! Show people what is happening to the penguin colonies and you will get a response.

    I have read about drowned polar bears and dead penguins, Why have I not I seen any pictures? Talk about scientific reticence! We have a duty to tell people what we see.

    Somebody needs to confront Rush Limbaugh with a very dead polar bear and a very dead penguin. That will get you some news headlines. Then do it on PBS, ABC, & CBS.

    Comment by Aaron Lewis — 22 Aug 2007 @ 7:22 PM

  98. Re # 77,

    Walt, thank you for your comments. As I stated at the start of my posting, I am a pretty average human being and possess no blinding intellectual insights into our present predicament. We do discuss here the problem of AGW, but as you will be aware, there are many other major issues pressing on humanity, due to our own actions, these include nuclear warfare, oil depletion, overpopulation, environmental damage, deforestation, the rape of the oceans; basically the imminent collision of humanity’s perceived and ever-increasing requirement for the planet’s resources and the inability of a finite planet to provide them, or a finite atmosphere to hold the pollutants. I am not a technophobe or alternative life-styler (though I certainly don’t criticise such people, generally I admire them), I appreciate how technology and science has liberated much of humanity from drudgery and disease and ignorance, and that life for many of us is no longer a constant battle for survival.

    But it seems to me that despite all the arguments for and against economic expansionism, Business as Usual, as you put it, we are in danger of arguing ourselves to oblivion. Take the Iraq war for instance, would we have got ourselves into such a predicament if we had taken on board a simple moral stance, war is immoral, and nothing other than a dire, credible, immediate and sufficiently damaging threat of enemy action should make it anything other? Doesn’t the vast majority of humanity shun war, abhor it; yet here was the world’s most advanced nation, and some of its friends, proceeding to a frightful war, and all wars are frightful, on some vague intellectual pretext.

    In a sense, isn’t what we are doing to the planet, akin to a war against nature, and isn’t dealing with the massive problems that face us all, also a war, against our own nature? In other words, aren’t so many of the problems we face basically just moral ones?

    I am not at all religious; I have become increasingly atheistic for a couple of decades, and much more definitively in the last few years. But as a humanist, I do still believe very strongly indeed in the ethical and spiritual dimension of humanity, and that most people, whatever religion or culture, will understand this. I think we have forgotten our ethical and moral duties to ourselves and our environment, we no longer bother considering the ethical dimensions of so much of what we plan and achieve, and in fact we are derided when we do. It is this lack of moral capacity in ourselves and our institutions, I believe, that has, mainly, brought us to the pass we are now in. For example, large corporations are often charged, and rightly, for their amorality in dealing with many of these matters – deforestation, human rights, workers’ health, bribery and corruption, the worsening of third world impoverishment, pollution etc. – and yet we are told that a corporation only has a duty to its shareholders, to maximise the return on their capital and that legally no other considerations are allowed. To which I would say, what sort of world is this that moral and ethical considerations are legally barred in some of the most important endeavours that mankind undertakes?

    Walt, you say “Those who argue in favor of a BAU approach are not necessarily oblivious to the self-destructiveness of that stance; they simply understand that it will be others, not themselves, who will face those consequences. At its base, this approach can be defended as practical and rational, at least as far as it serves the near-term interests of those who hold it.” Isn’t this the problem, something that may be practical and rational, for those that stand to benefit, isn’t practical or rational at all for many others. This argument is simply not defendable. Isn’t it just simpler to say, this attitude, this action, it is immoral, which it undoubtedly is, stop it now. It may have seemed, at the time, rational to the leadership and population of Germany for that country to invade Poland, and it was certainly practical, after all they did it, but by a long way, it wasn’t moral. Ditto Iraq.

    You go on to say My approach is this: man has greatly accelerated his ability to alter his environment (Gore’s “bigger shovel” example in AIT). Man has not necessarily accelerated his ability to understand the consequences of these alterations. To some extent this blindness is useful, because we don’t know enough about future conditions and capabilities to choose too far in advance. Apart from the obvious rejoinder that if we don’t know the consequences of our actions, we shouldn’t be doing them (if Germans knew what the consequences of invading Poland would be, would they have proceeded?), isn’t the contentious point the “bigger shovel”? I would suggest that the “bigger shovel” is in fact the “greedy shovel”. Do we need a bloody shovel in any case; wouldn’t “intelligent spadework”, in our present precarious position, be rather more appropriate? This is the moral argument; isn’t so much of what passes for desirable economic activity nowadays merely greed, pure and simple?

    I think many people would now agree that AGW is not merely the accidental or unavoidable by-product of a progressive civilisation, but is in fact the ignorant and heedless poisoning of our environment by greed, and is directly the result of the hubris of humanity, that we live in some parallel universe, where the normal laws of nature no longer apply. Our inability to see ourselves any longer as creatures of biology, just as dependent on the processes and rules of nature, as much as any tiger, eagle, dolphin or any other form of life, is the basic cause of so many of our present trials and tribulations. I still contend therefore that AGW is above all a moral question, of our relationships to each other, to all other living things and to the planet that sustains us.

    This all seems rather a long way from the remit of Real Climate in presenting the science of AGW, but, and I am sure I speak for most other contributors and readers, we have long since accepted the reality of the problem, most of us are becoming increasingly alarmed about the obvious urgency and severity of the AGW, and increasingly frustrated by humanity’s present inability to agree an effective strategy in dealing with it. Hopefully this discussion will help.

    Comment by John Monro — 22 Aug 2007 @ 7:36 PM

  99. Re 93 – Rlod B says: “Actually there has been a set of environmentalists that for some time now have the survival and enhancement of the human species way way down on the priority list. Granted they’re the fringe, but they’re fun to talk about…”

    I have no idea who you might be talking about. They would not be people that I, or anyone I know, would relate to. Care to say a little more about who they are and what their influence might be?

    Comment by Ron Taylor — 22 Aug 2007 @ 8:01 PM

  100. RE 97… PSSST Aaron.

    you forgot to RTFM and

    ” Cite personal experience running an environmental canvassing operation.”

    THAT, is some rich and creamy Irony.

    Recently Dr. Hansen discussed the concept of Ursafuct
    in an email from columbia. That would make a great thread here

    Comment by steven mosher — 22 Aug 2007 @ 8:02 PM

  101. http://www.biosurvey.ou.edu/oese/Straw_Man_Kit.JPG

    Comment by Hank Roberts — 22 Aug 2007 @ 8:17 PM

  102. “re 83: “a growing concern that the stance of some denialists may include a hidden agenda… ”
    I’m positive this is true, as it is for many proponents of the AGW theory. Might be best to just leave the factions of both camps alone, though I have to admit their cacophony sometimes just can’t be ignored.
    Comment by Rod B ”

    The ‘hidden agenda’ of people worried about AGW is simply the continuation of human and biotic existence and that of our human civilization. It’s a quality of life issue.

    Comment by catman306 — 22 Aug 2007 @ 8:29 PM

  103. The media have given interesting coverage to Tim Lenton and now to this story:
    http://www.enn.com/climate/article/22168
    Could you please offer a post on the emerging scientific perspectives on sea level rise potential?

    Comment by John Wilson — 22 Aug 2007 @ 8:52 PM

  104. Re: #98

    John,

    As I acknowledged in my first response, your points are valid and, in my mind, true. I come at the stewardship of the planet from the same standpoint that you do: if it’s bad for the planet, it’s bad for us.

    What I was trying to explain are two things: 1, having spent a great deal of time in discussions (and observing the rationale) of the general group known in this forum as “deniers”, I am aware that they consider themselves to be acting on moral principles. Many of them consider the AGW “crowd” to be the immoral ones, because the solutions being discussed have the potential to rein in economic growth. Many see that as hitting hardest at those who live in the most desperate poverty.

    2, with regard to the bigger shovel and accelerated consequences, it is an adaptation issue, isn’t it? Humans have not adapted to the consequences of these bigger tools as quickly as we have developed them. There of course must always be such a lag, because only experience can be the final arbiter of the relative “good” or “bad” of a new behavior. I suppose we can rule out many behaviors as clearly destructive (and yet, some will advocate them anyway); many others are much more ambiguous, and there is no clear way to know these things without experience.

    Hypothetically, we could be around the corner from a breakthrough technology that, within ten years of implementation, sucks the excess CO2 from the atmosphere. We simply don’t know. I’m sure there are many examples of a need for development, followed by some new breakthrough which delivers the needed solution. So, is it “practical” to work out all of the potential consequences of a new behavior? Or is it more practical to “wait and see” what those consequences are, and react to those? I would submit that the answer is “both”, depending on the circumstances. In the effort to meet mankind’s energy and sustenance needs, the industrial revolution was born. Would it have been practical to withhold deployment of these innovations on the theory that there were consequences we could not anticipate? Of course not.

    As I said above, the challenge is to decipher the clues as we go, and to do all that we can to avoid catastrophe. Toward that end, AGW is not only real but symbolic. I wrote in a different thread that the future of the nation state relies on the collective ability to deal with challenges such as this. If nations keep competing on the basis of short-term self interest, they will become irrelevant in the larger struggle to save mankind from man.

    A very serious topic, well worth discussing. I stand by my position that “morality” is not the crux issue, and in fact has the grave potential to bog down the entire debate as each “side” defends the “morality” of their views.

    Gore had it right: stick to the practical. Now, we just have to get everybody – or at least an overwhelming majority – to come to some sort of consensus on the accuracy of the science.

    THEN the real fun: what to do, who will it impact and how will it be funded?

    Comment by Walt Bennett — 23 Aug 2007 @ 10:14 AM

  105. re 99, just one for the drill, Ron (Gavin et al rightly so don’t like lots of this stuff): the folks who, with no reservations, put the inconvenience of the spotted owl over the economic viability of the people.

    Comment by Rod B — 23 Aug 2007 @ 11:06 AM

  106. re 102, Catman says, “The ‘hidden agenda’ of people worried about AGW is simply the continuation of human and biotic existence and that of our human civilization. It’s a quality of life issue.”

    High-minded contention, there, though I admit it probably does apply to the mainstream AGW proponents. But you don’t have to look hard to find the faction who clearly support the idea of diminishing the quality and development (they call it greedy wastefulness) of especially the West and U.S in particular, and find AGW a convenient tool.

    [Response: Fair point, but the answer to that is to argue that their conclusions do not follow from the premise, not to argue that AGW can't be problem because some people draw conclusions from it that you don't like. - gavin]

    Comment by Rod B — 23 Aug 2007 @ 11:17 AM

  107. Re 106: That, of course, would call for a debate (concept so dear to AGW opponents) about the objective reality of greed and wastefulness in the developped world. After all, there may be such a thing.

    Comment by Philippe Chantreau — 23 Aug 2007 @ 11:54 AM

  108. the folks who, with no reservations, put the inconvenience of the spotted owl over the economic viability of the people.

    Well, I guess you mean me, then, since I was on the board of the co-lead plantiff in the spotted owl lawsuit.

    My guess is you don’t know much about the history of the old-growth wars in the PNW.

    I’m curious though. Is there any particular reason why you believe the US Forest Service should be allowed to ignore federal law? When Congress passes laws saying “this is how our federal forests should be managed”, personally I think the USFS should obey them.

    If they did, after all, they wouldn’t've lost the lawsuit in such spectacular fashion.

    Feds break the law, conservationists get blamed for “not caring about people” when we force them to follow the law.

    Strange world.

    Do you believe the USFS should lie about the amount of old-growth forest when setting harvest levels? They did, for over a decade. The Wilderness Society spent $500,000 proving it (and after they did so, the USFS said “oh yeah, you’re right” less than a week later).

    There’s a reason why Jack Ward Thomas, when appointed head of the USFS by Clinton, sent a memo to every Forest in the country that started with these two points:

    1. We will obey the law
    2. We will tell the truth

    His point being that the USFS had done neither during the Reagan and Bush I administrations.

    BTW a huge majority of Oregonians support a total moratorium on old-growth logging, and our economy is doing fine, thank you. Old-growth veneer and saw mills were rapidly switching to second-growth before the spotted-owl shit hit the fan, and available old-growth would’ve run out in 10 to 20 years regardless. We’re still harvesting old-growth, with luck a couple percent of the original old-growth forest will remain in perpetuity. At least until AGW kills it off.

    Comment by dhogaza — 23 Aug 2007 @ 12:11 PM

  109. Alastair McDonald wrote: “… we assume that any species that developed intelligence would inevitably be aggressive, since it would have developed through the process of the survival of the fittest. Like us, they too would burn their planet’s fossil fuels as if there was no tomorrow. They too would not only cause the end of their civilisaton, but also the end the prospect of any new civilisation because the natural resources needed to advance beyond the stone age had already been squandered.”

    It is not a given that carbon-based fossil fuels would be abundant or even exist on other planets where technologically-capable species might evolve. The existence of large quantities of relatively easily accessible fossil fuels on Earth is the result of particular specific events in the Earth’s geological history. Indeed, it is interesting to contemplate an alternative history of the human species on an Earth where fossil fuels either never formed, or formed under conditions such that they remained inaccessible and unknown to humanity. Where would we all be today if humanity had never had all that coal or oil to burn over the last century or two?

    Comment by SecularAnimist — 23 Aug 2007 @ 1:01 PM

  110. Rod B wrote: “Actually there has been a set of environmentalists that for some time now have the survival and enhancement of the human species way way down on the priority list.”

    I don’t know of any such “environmentalists”. I do know of environmentalists who recognize that the human species is but one of many species that have evolved as part of the Earth’s biosphere, and that our survival and well-being as a species is utterly and completely dependent on the survival and well-being of the web of life of which we are a part, and thus when through ignorance, shortsightedness and/or greed we engage in activities that are destructive to that web of life, we are destructive to ourselves as well.

    The basic paradigm that sees the world as consisting of the human species on the one hand, and everything else in the living world as “resources” or “the environment” for the consumption of human beings on the other hand, is at the root of our most serious problems, global warming being at the top of the list. No such duality actually exists. Just as that false duality is at the root of the problem, an appreciation and understanding of the reality of wholeness is at the root of the solution.

    Comment by SecularAnimist — 23 Aug 2007 @ 1:10 PM

  111. Re #106: [But you don’t have to look hard to find the faction who clearly support the idea of diminishing the quality and development (they call it greedy wastefulness) of especially the West and U.S in particular, and find AGW a convenient tool.]

    In addition to the point Gavin makes, you should also consider that quality of life (beyond the basics of e.g. getting enough to eat) is largely subjective. I certainly find that some of what you refer to as development in fact reduces my quality of life.

    If you think that gives me a motive for using AGW as a tool, then I’d just have you reflect on how much use one gets out of a broken tool.

    And #105: [...put the inconvenience of the spotted owl over the economic viability of the people.]

    As it happens, I used to work on a logging crew in my younger days, ’til spotted owls and the like made jobs hard to find. Yet here I am, making way more money than I ever would have, if I’d thought of myself as just a logger and sat around bewailing the evil environmentalists and the loss of my God-given right to cut down every tree in sight. Seems like I ought to be thanking those folks for increasing my economic viability, wouldn’t you say?

    Comment by James — 23 Aug 2007 @ 1:17 PM

  112. I can somewhat relate to James’experience. 20some years ago I had an idea of doing forestry in equatorial Africa, where I grew up in part. Seeing 1st hand the practices of most logging companies there discouraged me of doing so, although at the time there was nothing I wanted more than to live in the African forest. There are countless examples of how quality of life is better when we protect our world. Look at the industrial devastation of former soviet satellite countries or the difference between Dominican Republic and Haiti. The US has the most stringent environemental regulations in the world (except possibly for NZ) and the single largest economy. All those lamenting the fate of NW loggers never comment on that of all the workers who lost their jobs to globalizaion, even in cases where an entire community would mobilize to give the best possible deal to a corporation.

    Comment by Philippe Chantreau — 23 Aug 2007 @ 6:39 PM

  113. The following article claims 12F of cooling over several decades by climate modeling for 20,000 nuclear explosions.

    http://www.nature.com/climate/2007/0709/full/climate.2007.39.html

    As far as I know, between the US, Soviets, Chinese, French and British, there has been somewhere between 500 to 750 above ground weapons test between 1944 to 1968.

    This works out to between 0.3 to 0.45F of cooling. That could go a long way into explaining stabilization of Global Temperatues between the 1940′s to 1970.

    Don’t see anything in the IPCC report about this.

    Could it have been considered and rejected by the IPCC?

    Are there good reasons to reject it?

    Comment by Andrew — 23 Aug 2007 @ 7:43 PM

  114. Try the Search box here for more on this from previous discussions.

    The nuclear war scenarios assume primarily airbursts over industrialized and populated areas, with firestorms and large volumes of soot as a result, even if the fireballs were high enough not to touch the surface directly, and some ground level explosions to maximize damage on hardened sites, also producing large amounts of soot and debris.

    The atmospheric nuclear tests were primarily over desert or coral atolls, and many were airbursts set off high enough that the fireball did not touch the ground, so there was relatively little material (and even less burnable material) in the bomb cloud; that was intentional, to reduce fallout.

    Comment by Hank Roberts — 23 Aug 2007 @ 8:15 PM

  115. “The problem is how to find the Jeffrey’s prior when the likelihood function isnt available analytically as a function of the parameters.”

    That turns out not to be a problem for several reasons. There are ways to estimate parameters with Jeffrey’s rule even for models of unknown form. I don’t know if anyone in climate science is using that sort of thing, but it can be done. Essentially you embed your model in an infinite dimensional function space, although you know full well that you will actually be working in a finite dimensional subset. But you do not have to know that finite dimensional subset. It turns out that you can choose the infinite dimensional embedding in such a way that you can easily compute the Jeffreys’ prior estimate, or you can also choose it so that the Jeffrey’s prior will be locally uniform, it is more a matter of style which of these you do. The “magic” happens that the Jeffreys’ prior regularizes your estimates in the infinitely many directions which your data provide no information.

    Whether or not this ends up being a good estimator really depends on whether you have been intelligent enough in choosing the embedding; there are lots of ways of doing it. I’m not aware of anyone in climate science who is using these techniques, but the guys in climate science (GCMs) who I did my Ph. D. with back in the 1980s would have no trouble picking up those tools.

    Note: I am not a climate scientist now, if I ever was one, but I am a mathematician who is active in the field of high dimensional estimation.

    Comment by Andrew — 23 Aug 2007 @ 8:18 PM

  116. Eric – Well, I suppose that means that you agree with what the climate science community has been saying for some time now – anthropogenic global warming is indeed a reality. However, you seem to think that this will be (at least for you) beneficial? Let’s see: agricultural losses due to a destabilized climate, increased heat waves, droughts, and flooding, more intense and frequent hurricanes, millions of climate refugees due to sea level rise…I’m not seeing a whole lot of benefits here.

    Andrew – I looked at that article. That would be the simultaneous explosion of 20,000 nuclear weapons, right? No doubt you wouldn’t mind too much if someone dropped a kilo of sand on your head from a height of two meters – try doing that with 20,000 kilos of sand, all at once. Also see Hank’s comment on soot and fire from burning cities (vs. isolated Pacific coral atolls). It’s the immediate stratospheric injection of large amounts of aerosols that leads to cooling.

    Take another example – Pinatubo’s explosion, which ejected 5 billion cubic meters of ash and debris to heights of up to 30 kilometers in the atmosphere.

    “The cloud over the earth reduced global temperatures. In 1992 and 1993, the average temperature in the Northern Hemisphere was reduced 0.5 to 0.6°C and the entire planet was cooled 0.4 to 0.5°C. The maximum reduction in global temperature occurred in August 1992 with a reduction of 0.73°C. The eruption is believed to have influenced such events as 1993 floods along the Mississippi river and the drought in the Sahel region of Africa. The United States experienced its third coldest and third wettest summer in 77 years during 1992.”

    This served as a good confirmation that climate models were handling aerosol effects correctly. Note that Pinatubo was in the tropics (see Current volcanic activity and climate? RC 2006. I just mention this because the paper you reference is really all about the long lifetimes of aerosols – and the Pinatubo test case provided verification for modelers. Science just keeps on advancing…

    Comment by Ike Solem — 23 Aug 2007 @ 9:20 PM

  117. Re 109. “Where would we all be today if humanity had never had all that coal or oil to burn over the last century or two?”

    We wouldn’t be waiting for ice sheets to disintegrate and to submerge dozens of nuclear reactors sitting on the shoreline … or waiting for the redistribution of increased ocean waters to trigger earth quakes and undermine the other nuclear reactors that aren’t at the shoreline.

    The situation is an emergency.

    Comment by Michael — 24 Aug 2007 @ 2:46 AM

  118. Regarding nuclear reactors, an estimate of 5 metres plus can be taken from here

    http://environment.newscientist.com/article.ns?id=mg19526141.600&feedId=climate-change_rss20

    and put into here

    http://flood.firetree.net/

    to check against the locations of installations which are given here

    http://www.insc.anl.gov/pwrmaps/

    each of which can also be viewed using Google Earth.

    Mitigation is essential. Mitigation is doable. Action is required now.

    Comment by Michael — 24 Aug 2007 @ 4:25 AM

  119. Hi Ike, you won’t see benefits if you don’t look for them. You asked for an example, I gave you one of many. Of course AGW is a reality, just as GW was and is (to some debatable extent). Getting back to the original point, global tipping points are not currently a reality and it is very unlikely that human tipping points will happen either (e.g. your example of refugees) as long as the current trends continue: globalization reducing world poverty, democratization, economic progress, free migration.

    Comment by Eric (skeptic) — 24 Aug 2007 @ 6:02 AM

  120. [[It is not a given that carbon-based fossil fuels would be abundant or even exist on other planets where technologically-capable species might evolve. The existence of large quantities of relatively easily accessible fossil fuels on Earth is the result of particular specific events in the Earth’s geological history. Indeed, it is interesting to contemplate an alternative history of the human species on an Earth where fossil fuels either never formed, or formed under conditions such that they remained inaccessible and unknown to humanity. Where would we all be today if humanity had never had all that coal or oil to burn over the last century or two?]]

    Burning wood and biofuels and getting electricity from biofueled turbines and perhaps windmills?

    Comment by Barton Paul Levenson — 24 Aug 2007 @ 7:15 AM

  121. [[The following article claims 12F of cooling over several decades by climate modeling for 20,000 nuclear explosions.
    http://www.nature.com/climate/2007/0709/full/climate.2007.39.html
    As far as I know, between the US, Soviets, Chinese, French and British, there has been somewhere between 500 to 750 above ground weapons test between 1944 to 1968.
    This works out to between 0.3 to 0.45F of cooling. That could go a long way into explaining stabilization of Global Temperatues between the 1940’s to 1970.
    Don’t see anything in the IPCC report about this.
    Could it have been considered and rejected by the IPCC?
    Are there good reasons to reject it?
    ]]

    Yes. The nuclear winter scenario involves the nuclear destruction of cities, and consequently large amounts of soot lofted into the stratosphere. Individual nuclear tests don’t generally do that. You got some of it with Hiroshima and Nagasaki, but not enough to be significant.

    Comment by Barton Paul Levenson — 24 Aug 2007 @ 7:18 AM

  122. Re 120:

    Burning wood and biofuels and getting electricity from biofueled turbines and perhaps windmills?

    It’s important to remember that biofuels, wind and solar themal power aren’t “expensive”, as in, “astronomically out of this world”, they are simply “more expensive” and much of that because fossil fuel based technologies got the head start, economies of scale kicked in, and further research into alternatives halted. As fossil fuels increase in cost, those other technologies become attractive.

    We, of course, wouldn’t have had the solar photovoltaic revolution that we’re now seeing, with falling solar cell prices, from the outside, but it is reasonable that solar thermal would have emerged as the alternative to cutting down the forests for fuel. Once solar thermal developed, we’d have had all the electricity we needed, and many of the other technologies we have today would have come in their due course. We’d all be riding electric cars, or electric city buses, and we’d be living in homes with televisions (or whatever ;) ), working lights, and all the other essentials. Electricity was the primary enabler, before the internal combustion automobile and the massive oil fields which supported them.

    The only question I have about climate, long term, in a “renewable energy” world, is land use — how do land use changes in some utopian “renewable energy only” scenario play out? If we drive towards biofuels-based energy, complete with massive land use changes to support fuel crops, how does that affect the climate, as compared to a solar-fuels scenario? If we get smart and sequester as much of the ‘scrap’ as possible, can we move towards negative carbon emissions.

    My personal thoughts are that variability in weather will cause solar-fuels to compete favorably with fuel crops — how much more energy can be produced on an acre of land with wind, solar thermal or photovoltaic compared to fuel crops? Unless I’m mistaken, I’m thinking that solar thermal is going to be the greatest output, unless there is sufficient wind that a combination of technologies — solar thermal electric plants with wind towers mixed in.

    Comment by FurryCatHerder — 24 Aug 2007 @ 8:57 AM

  123. Re 119 Eric, I think you may be assuming that positive and negative impacts of AGW will, more or less, average out over the globe, so all will be well. It will not work that way. Any positive effects will be regionally limited and are unlikely to be coincident with the worst negative ones. Think of the tensions that will be created between areas of relative benefit and areas suffering the worst negative consequences.

    The issues are likely to be the most basic: food and water. What, for example, will the Chinese and Indians do when they begin to run low on fresh water, used for both consumption and food production, as a result of the loss of the Tibetan glaciers? And this will only be one problem among many that arrive simultaneously. It is hard to imagine them rolling over and meekly watching their populations die down to a level that is sustainable in the new environment. Of course, technology will provide some mitigation, but…

    Comment by Ron Taylor — 24 Aug 2007 @ 8:58 AM

  124. All, Actually I agree with the preponderance of the words posted to refute my assertions. But, strictly logically speaking, they don’t refute my assertions.

    Gavin makes a good point (106). Hidden agenda AGW “proponents” do not logically detract from the scientific arguments for AGW, though they might cause an unfortunate deleterious reaction at nobody’s fault. Same goes for the hidden agenda skeptics.

    Comment by Rod B — 24 Aug 2007 @ 1:05 PM

  125. re 121

    The nuclear winter scenario involves the nuclear destruction of cities, and consequently large amounts of soot lofted into the stratosphere. Individual nuclear tests don’t generally do that. You got some of it with Hiroshima and Nagasaki, but not enough to be significant.

    =============

    I recall reading recently that the amount of particulate matter tossed up in the atmosphere by Krakatoa in 1883 was along the order of 13,000 times that of Little Boy…

    Comment by J.S. McIntyre — 24 Aug 2007 @ 1:24 PM

  126. Eric, your assertion that global tipping points don’t exist is completely unsupported and is barely worth replying to. Saying that they don’t ‘currently’ exist is meaningless, particularly considering the amount of change that is in the pipeline already – even if we were to halt the use of fossil fuels today, the momentum will keep warming the planet for decades.

    You haven’t given any evidence that there will be any benefits to the current business-as-usual projections of global warming, other than to claim that winters will get warmer while summers won’t – which is completely unsupported. The only arguments you give imply future economic benefit, so let’s look at that. Statistical Analysis Debunks Climate Change Naysayers

    From the above link:
    ““These arguments are moot,” says Peter Tsigaris, an economist at Thompson Rivers University, in Kamloops, BC. He continues: “The important question is the cost of these opinions being wrong relative to the cost of the IPCC report being wrong in its assessment.” ”

    “Tsigaris asked, “A claim is made that global warming is caused by humans. Set up the null and alternative hypothesis for this claim. As a scientist, you want to test that the above claim is true beyond a reasonable doubt. Discuss in terms of the type I and type II errors that are associated with the claim, and discuss the implications of the errors in terms of their associated costs.””

    A type II error would be to conclude that global warming is not caused by humans, when in fact it is. A type I error would be to conclude that global warming is caused by humans, when in fact it is not.

    To quote again,
    “It is obvious that a type II error, being unaware that global warming is caused by humans and maintaining our current living styles, is much more serious than a type I error which argues that humans are the cause when they are not, in terms of the costs,” he says. “Rising sea levels, temperature and precipitation caused by human lifestyles will have an impact on our health, agriculture, forestry, water, coastal areas, as well as on other species and natural areas,” he says, adding that “this analysis also confirms the Stern Review on The Economics of Climate Change which suggests that the cost of taking action today is way less than the cost of continuing the current path we have chosen.”

    Note – this is a purely statistical economic argument – but there are also statistical physical arguments as well as first principles physical arguments that confirm the reality of fossil fuel-induced global warming. There really are no valid scientific or economic arguments for doing nothing about the problem.

    Comment by Ike Solem — 24 Aug 2007 @ 2:50 PM

  127. re: 120
    “globalization reducing world poverty, democratization, economic progress, free migration.”

    Eric: why are you assuming this?

    I’d claim there is plausible skepticism on the economics issues, for which I’d cite:

    1) David Strahan, The Last Oil Shock, pp 114-130. [Amazon Canada or UK]
    http://www.lastoilshock.com/

    2) Hall, Lindenberger, Kummel, Kroger, Eichhorn, The need to reintegrate the natural sciences with economics. BioScience vol 51, no 8 (August 2001), 663-673. http://www.ker.co.nz/pdf/Need_to_reintegrate.pdf.

    3) Ayres & Warr, Accounting for Growth: the role of physical work.
    Structural Change & Economic Dynamics, 16(2): 181-209.
    http://www.iea.org/Textbase/work/2004/eewp/Ayres-paper1.pdf
    http://cres.anu.edu.au/events/sem-marr2007.php

    Summary: globalization and increasing wealth/person collides with Peak Oil.

    a) Long-term economic growth depends not just on labor and capital, but on energy, i.e., more (effective) energy = richer, which in turn depends on energy used and efficiency of its use. Other things being equal, farmer+tractor+gas is richer than farmer+horse is richer than farmer with no draft animals; the same output is produced with less people, which means people are richer.

    The authors above claim that mainline neoclassical economics doesn’t seem to recognize the importance of energy in increasing wealth, and from an hour spent sampling the (extensive) Economics section of the Stanford bookstore, I tentatively agree with them. I get really nervous with things like “Solow residuals” where the residuals are bigger than the growth explained; including energy seems to give much better fits.

    A lot of people seem to assume that worldwide GDP/person will automagically keep increasing, incidentally claiming that means that climate mitigation efforts should be deferred to a richer generation. This is unclear.

    b) Cheap oil has been wonderful: our civilization was built on it.
    Peak Oil happens 2015 +/-5 years, which, coupled with increasing demand from places like India and China, mean that the free ride on cheap oil will soon end, well within the lifetime of existing vehicles and especially infrastructure investments being made. Assume, for example, $10/gallon gas in CA,as well as 3X jet fuel [~25% of airline cost].

    How do people think that will affect globalization? Does it make sense to build Heathrow Runway 6, tearing down 600 homes, to be done by 2020 or later, to handle 2X or 3X larger number of passengers by 2030? Will there be 2X or 3X more passengers if prices go up? How many poor third-world farmers will get tractors? As of 2003, India was supposed to have 15M electric and 6M diesel irrigation pumpsets, and the agricultural consumption of electricity was 27% of the total. http://www.hwwi.org/uploads/tx_wilpubdb/HWWI_Research_Paper_4.pdf.
    Substantial investment and time will be needed to convert to solar, although they’re trying.

    The Stern Review (“The Economics of Climate Change” doesn’t even mention Peak Oil), although Chapter 11 covers energy costs somewhat.

    c) Over the next 50 years, as cheap oil winds down, followed by cheap natural gas a few decades later, we’ll need to have a major/expensive turnover to solar, wind, biofuels, (nuclear?) JUST TO STAY EVEN in energy/person (assuming no population growth). There will be a strong temptation to use more coal to keep the lights on. It is simply NOT obvious that we’ll be increasing the (efficient-energy)/person on a world scale at the rate we’ve done in the last century, even with the recent boost from IT seen in the models. Exactly how do you expect to reduce world poverty if the energy/person stops growing.?

    Climate models at least have physics in them; it seems that many economics models don’t explain the sources of wealth and growth very well, which is why I trust physics models much more.

    I’d be happy to have someone read the cited sources and knowledgably explain why they’re wrong … but vague assumptions about globalization and increased wealth aren’t very convincing.

    Comment by John Mashey — 24 Aug 2007 @ 2:53 PM

  128. I agree with John. For all the buzz on the “new” economies, there is no escaping the basics. Wealth is not generated out of nothing. Another important thing to consider is one that has become a favorite of denialists: poor countries. As oil and gas supplies decrease, who is going to be able to afford what’s left, poor countries?

    Comment by Philippe Chantreau — 24 Aug 2007 @ 9:37 PM

  129. John,

    Per-capital energy isn’t the whole issue — the U.S. has already reduced per-capita oil consumption. That peaked back in the 1970′s. The growth in consumption, per-capita, on a global basis is slowing already, and wealth continues to outpace per-capita oil consumption.

    The thing is to look at the past and see how the adaptation to expensive oil occurred, because in the past, oil was much more expensive than it is even today. Changes in technology have always “trickled down” before becoming ubiquitous. Before Ford’s Model T, the other automobile manufacturers were selling cars for 10 times what Ford sold them for. The same thing is happening, more or less, with various forms of hybrids. It was cheaper to have a horse and buggy, than a horseless carriage — up until it wasn’t. And that’s the point we’re approaching with hybrids. It will be cheaper (and I’d argue it is already) to own a hybrid over its lifetime, than not.

    That’s always how it works — the early-adopters are the affluent, the enthusiast, or the hobbyist. Look at how it went in our profession — my first real computer was $8,000, didn’t have a hard drive (it was a $4,000 option), came with 128K, and ran at a mind numbing 6MHz. The equivalent cost today would be on the order of $20,000 after inflation, even though it has less memory and a slower processor than the cell phone Sprint gave me for free (after rebate and 2 year service agreement ;) ) Who is richer — someone with a circa 1980 “personal” computer, or someone with a Blackberry, iPhone or Treo? Now for the tricky part — which consumes more power: a circa 1980 “personal” computer, or my 64MB Tungsten T3? Your assumption that “energy” and “wealth” are bound unalterably is flawed.

    Look at where “oil” goes, and look at how many of those uses are “required”. How much “oil” is turned into disposable plastics because the oil to make disposable plastics is so cheap? Will plastic packaging continue to be used by corporations when oil goes to $120 / bbl? $150 / bbl? Consumption is high because costs are low. That’s all — no great mystery.

    “Cheap oil” is an artificial construct — “oil” was not cheap when it was first discovered, and neither was “solar” when it was first being deployed. “Oil” is a developed technology. “Personal Computers” are a developed technology. The technologies that can replace non-renewables aren’t yet completely developed, though they are getting there.

    The point, John, is that if computers and cars hadn’t drastically fallen in price, they’d still just be the domain of the rich. The computer hardware in my house today would have cost in the billions of dollars in 1980. I’m not a billionaire, or even a millionaire. I’d have been left out of the “Automobile Revolution” if car prices had stayed where they did, after adjusting for inflation. In the 1950′s the solar panels on my roof would have cost over $600,000 — without adjusting for inflation. Who has more wealth? Someone with the 1950′s equivalent value of solar panels on their roof, or someone with that value in 2007? Now for a more modern question — who has more wealth: someone with a house full of incandescent bulbs (cheap initial cost, high recurring costs), or someone with a house full of CFLs (high initial cost, low recurring costs)? If the examples I’ve given here — all of which use less energy at higher values of “wealth” aren’t proof that you’re wrong, I don’t know what is.

    These costs aren’t static — if they were few of us could afford cars, and fewer still could afford computers. Just as the “Information Age” started in the 1980′s, we are at the start of the “Energy Age”, and that’s why the “renewable energy won’t do it” / “more energy is more wealth” skeptics are wrong.

    Comment by FurryCatHerder — 25 Aug 2007 @ 8:30 AM

  130. Ron (#123), I don’t assume positive and negative will be equal, I just don’t ignore the positives. Just as you say any positive impacts will be localized, obviously negative ones will be too. In your example the Chinese and Indians will have to import more food and possibly water or develop other sources. That does not seem problematic to me, people do that all time even without being forced to.

    Ike (#126), when I read discussions of global tipping points like the one here a year or two ago, I saw cherry picking and ultimately non-quantitative analysis. The discussions tend to hypothesize positive feedbacks without hypothesizing negative ones. Since quantitative CO2 forcing to date produces more warming than seen to date, there are obviously already some negative feedbacks in the mix. The IPC07 report states that the carbon flow percentages have remained unchanged since 1958. That doesn’t mean other feedbacks can’t occur (e.g. methane) but those are short term and those are more easily solved with countermeasures than the long term (“baked-in”) type of warming you seem to be referring to.

    John (#127) peak oil is a good point. But the fact is globalization has equalized incomes around the world. Middle class Americans have seen stagnant incomes while the percentage of $1/day poor has drop from about 40 to 20% (IIRC, numbers were from CATO). No doubt peak oil will lower the global rate of growth that has resulted from globalization, but it won’t fundamentally change it. The Indians and Chinese, for example, can build solar panels which will easily pay for fuel used for shipping them around the world. Our per capita energy use is flat despite our economic growth. The rest of the world will quickly catch up in efficiency given the economic motivations.

    Comment by Eric (skeptic) — 25 Aug 2007 @ 8:58 AM

  131. FurryCatHerder (129), like your post. Bear in mind that costs don’t always go down (at least greatly), and their sometimes hard to predict, especially for the future! Another minor caveat: hybrid owners have yet to reach the whole “new and improved” costly concept of replacing tires and batteries at NTB. An interesting sidebar: Henry Ford built a very good prototype car in the 30s with a mostly plastic body that came from renewables, but, unfortunately, mostly hemp which was becoming a really stupid high hurdle. It is not out of the question today, I would guess.

    Comment by Rod B — 25 Aug 2007 @ 11:25 AM

  132. Re #129: [...who has more wealth: someone with a house full of incandescent bulbs... or someone with a house full of CFLs...?]

    We could even extend that question: who has more wealth, the person who leaves the lights on because energy is cheap, or the one who turns them on only when needed?

    Comment by James — 25 Aug 2007 @ 1:46 PM

  133. Re 130 – Eric says: “Just as you say any positive impacts will be localized, obviously negative ones will be too. In your example the Chinese and Indians will have to import more food and possibly water or develop other sources. That does not seem problematic to me, people do that all time even without being forced to.”

    Yes, the example of the Tibetan glaciers is a local impact, but that “locality” includes most of populated Asia, with maybe three billion people. Replacing the lost water will be a huge problem, and it will be urgent. I cannot imagine how it will be as easy as you assume.

    Comment by Ron Taylor — 25 Aug 2007 @ 2:29 PM

  134. By following the articles on

    http://biopact.com

    one discovers that the poor countries iin the semi-tropivcs and tropics are moving to bioenergy as rapidly as they can…

    Comment by David B. Benson — 25 Aug 2007 @ 3:01 PM

  135. (oops, sorry, computer problems, lost half the post, throw previous away).

    re: #129 F.C.H. #130 Eric

    I *never* said per-capita energy was the whole issue [that’s like saying CO2 is the *whole* issue in climate change :-) Since I mentioned efficient-energy I think the end result matters (not just the energy input), and my house has been filled with CFLs for a long time.

    I did say:

    “I’d be happy to have someone read the cited sources and knowledgably explain why they’re wrong … ”

    Haven’t seen that yet…

    Your examples are rich-world high-tech consumer products, one category of which (computers) is famous for the rapidity of cost-reduction. These have little to do with where this started: “globalization reducing world poverty”, because that primarily means reducing rural poverty [63% of those on biofuels is certainly a good idea: they can’t afford much oil,and maybe they can just skip that phase (akin to skipping wires for telcom in favor of cellphones).
    ========

    This may be getting further OT for RC, but really, one has to bring the same kind of analysis (numbers, relevant facts, cites) to the problem.

    This may be getting further OT for RC, but really, one has to bring the same kind of analysis (numbers, relevant facts, cites) to the problem.
    “vague assumptions about globalization and increased wealth aren’t very convincing.”

    Comment by John Mashey — 25 Aug 2007 @ 5:56 PM

  136. “Ike (#126), when I read discussions of global tipping points like the one here a year or two ago, I saw cherry picking and ultimately non-quantitative analysis. The discussions tend to hypothesize positive feedbacks without hypothesizing negative ones. Since quantitative CO2 forcing to date produces more warming
    than seen to date, there are obviously already some negative feedbacks in the mix.
    Comment by Eric (skeptic) — 25 August 2007 @ 8:58

    Looking at Cryosphere Today it appears that an extra million square km has melted in the NH, also the SH maximum looks like it will be a million square km short so that represents a considerable excess of energy stored in the cryosphere compared with last year.

    Comment by Phil. Felton — 25 Aug 2007 @ 6:27 PM

  137. Isn’t it a little paradoxical to insist on effects that will (supposedly) be “local” and yet place them in the context of interactions between countries that are “global”? I don’t believe that anything can be truly local anymore. LA gets a good part of its smog particulates from China, the mountains and streams in the Pacific Northwest (where I live) receive more mercury than I’d want from that same place, crossing the all Pacific! The full influence of the Asian Brown Cloud is unclear (no pun intended). It seems to me even weather isn’t entirely local, if it affects activities in ways repercuted across the Globe through trade agreements. We’re all in this together, eventually.

    Comment by Philippe Chantreau — 25 Aug 2007 @ 8:29 PM

  138. Ron (#133) The glaciers store water seasonally so some dams would have to be built to store the water. Not easy, but doable. The water supply itself will be there, the Tibetan plateau itself will tend to keep the precipitation consistent.

    John (#135) FCH said it better than I did. The technology he describes is increasingly being pushed into the developing world. Like you say, it doesn’t make sense to run copper wires when the air is free and the cell phones and cell network have plummeting costs. These are simple facts, not vague assumptions. Globalization is colliding with the politicians looking for a scapegoat long before we get to peak energy. The main problem for Americans is that we are relatively overpaid and globalization will equalize that.

    Comment by Eric (skeptic) — 25 Aug 2007 @ 8:37 PM

  139. I was digging some for data on the US projected for 2095, Southeast, but discovered the following from back in July from the Union of Concerned Scientists on the US NE…

    Global Warming Will Hit U.S. Northeast Hard Unless Action Taken Now;
    Long-term Severity Depends On Near-term Choices, Scientists Say
    July 11, 2007
    http://www.ucsusa.org/news/press_release/global-warming-to-hit-0044.html

    First the temperatures…

    Under the higher-emissions scenario, winters in the Northeast could warm by 8 F to 12 F and summers by 6 F to 14 F above historic levels by late this century. But under the lower-emission scenario, temperatures during Northeast winters are projected to warm only 5 F to 8 F above historic levels by late-century, and summers by just 3 F to 7 F.

    Then the floods (assuming a nice, neat, linear and entirely unrealistic response on the part of Greenland and the West Antarctic Peninsula)…

    Coastlines: Global sea level is conservatively projected to rise 10 to 23 inches under the higher-emissions scenario and 7 to 14 inches under the lower-emissions scenario. Using these estimates, cities such as Boston and Atlantic City can expect a coastal flood equivalent to today’s 100-year flood every two to four years on average by mid-century and almost annually by the end of the century under either scenario. New York City is projected to face flooding equivalent to today’s 100-year flood once every decade on average under the higher-emissions scenario and once every two decades under the lower-emissions scenario by century’s end.

    PDF summary and report linked to in the article….

    Comment by Timothy Chase — 25 Aug 2007 @ 10:02 PM

  140. The mathematical physicist v. Neumann once said to his young collaborators: “If you allow me four free parameters I can build a
    mathematical model that describes exactly everything that an elephant can do. If you allow me a fifth free parameter, the model I build will forecast what the elephant will say.”

    Isn’t the same problem that portrays relying on Climate Modeling as predictors?

    [Response: Climate models aren't statistical fits to data, and the climate system is much more complex than just a few degrees of freedom, and the reason why climate models are used is because they have shown themselves to be useful - their predictions have matched observations for long term trends, responses to volcanoes, to El Niño, to orbital forcing etc. See here for more discussion:
    http://www.realclimate.org/index.php/archives/2007/01/the-physics-of-climate-modelling/ - gavin]

    Comment by Carter Alexander — 25 Aug 2007 @ 11:44 PM

  141. 2nd try, had computer/network problems; 135 was supposed to be:

    re: #129 F.C.H. #130 Eric

    I *never* said per-capita energy was the whole issue [that’s like saying CO2 is the *whole* issue in climate change :-) Since I mentioned efficient-energy I think the end result matters (not just the energy input), and my house has been filled with CFLs for a long time.

    I did say:

    “I’d be happy to have someone read the cited sources and knowledgably explain why they’re wrong … ”

    Haven’t seen that yet…

    Your examples are rich-world high-tech consumer products, one category of which (computers) is famous for the rapidity of cost-reduction. These have little to do with where this started: “globalization reducing world poverty”, because that primarily means reducing rural poverty [63% of those on biofuels is certainly a good idea: they can’t afford much oil,and maybe they can just skip that phase (akin to skipping wires for telcom in favor of cellphones).
    ========
    This may be getting further OT for RC, but really, one has to bring the same kind of analysis (numbers, relevant facts, cites) to the problem.
    Like I said:
    “vague assumptions about globalization and increased wealth aren’t very convincing.”

    Comment by John Mashey — 25 Aug 2007 @ 11:53 PM

  142. Re #138: [The glaciers store water seasonally so some dams would have to be built to store the water. Not easy, but doable.]

    I would like some practical ideas on just how one would do this. I’ve tried to think it out, but I can’t come up with anything that wouldn’t require many, many thousands of dams to even approximate the sort of storage than an alpine snowpack provides.

    Maybe your problem is that you are only looking at the far downstream end of the water flow, the urbanites and irrigated fields down in the flatlands, and forgetting that there is a very large land area upstream. What happens to that?

    Comment by James — 26 Aug 2007 @ 12:53 AM

  143. re: # 140, sorry, I’m having some odd problem in cut-and-paste (?) where 80% of the post (in the middle) seems to get dropped when on the way to RC. I hope this makes it.

    ….
    Your examples are rich-world high-tech consumer products, one category of which (computers) is famous for the rapidity of cost-reduction. These have little to do with where this started: “globalization reducing world poverty”, because that primarily means reducing rural poverty [63% of those on biofuels is certainly a good idea: they can’t afford much oil,and maybe they can just skip that phase (akin to skipping wires for telcom in favor of cellphones).

    ….

    Comment by John Mashey — 26 Aug 2007 @ 1:16 AM

  144. James (#140), we’ll have to ask Ron (#123) what he meant by loss of Tibetan glaciers, but I think there will still an annual snowpack with some water storage. There’s not a lot of numerical observations of decreased Aug-Sep runoff, but there’s a projection of 10 or 20% loss here: http://www.glaciers.pdx.edu/granshaw/Chapter06.pdf For higher altitude glaciers the immediate effect will be a rise in the summer pulse followed in the long run by a smoother annual outflow depending on precipitation patterns.

    Comment by Eric (skeptic) — 26 Aug 2007 @ 8:17 AM

  145. Re #145: [For higher altitude glaciers the immediate effect will be a rise in the summer pulse followed in the long run by a smoother annual outflow depending on precipitation patterns.]

    It appears that you’re still thinking of the effects way downstream as the only important ones. So let’s forget about Tibet for a bit (since I don’t have any firsthand experience), and consider something a lttle closer to home: the snowpack in the Sierra Nevada, Cascades, or Rockies.

    You have a snowpack that typically lasts into June, or even longer in some areas. The gradual melting of this snowpack allows a lot of it to sink into the ground, where it replenishes groundwater, rather than running off immediately as heavy rains mostly do. That groundwater supports the vegetation during the half of the year when there’s little or no precipitation.

    So how do you propose to replicate this with dams? Seems to me that to even make an attempt would take many small dams on every little stream – and that attempt wouldn’t do a very good job of replicating what the snowpack does for free. (Indeed, the snowpack is a source of profit, from all those who will e.g. pay to ski on it.)

    Comment by James — 26 Aug 2007 @ 1:02 PM

  146. Re 145 – Eric, there has been quite a lot about this in the news in recent years. The Tibetan plateau, with some 46,000 glaciers, has been warming faster the the rest of the NH. Some reports have indicated very rapid glacier retreat. You prompted me to do a limited search for sources, but do not have time for a more thorough search. We are leaving on vacation tomorrow and I will be out of touch for two weeks.

    You may want to have a look at this yourself. Human suffering aside, a serious loss of water for China and/or India could be very destablizing and something of global concern.

    Some news sources are here:

    http://www.foxnews.com/story/0,2933,193970,00.html

    http://www.commondreams.org/headlines06/0507-05.htm

    http://news.independent.co.uk/world/asia/article2600243.ece

    http://www.chinadaily.com.cn/english/doc/2004-10/05/content_379891.htm

    http://www.sciencedaily.com/releases/2007/07/070720163907.htm

    A more scholarly item from the Chinese Academy of Sciences is here

    http://www.wanfangdata.com.cn/qikan/periodical.articles/kxtb-e/kxtb2000/0007/000718.htm

    Like I say, this was a quick search and these are not necessarily the best available, just the best I could come up with in the time available.

    Comment by Ron Taylor — 26 Aug 2007 @ 3:28 PM

  147. re: #135, #141, #145 Sorry, problem seems to be that an innocent-looking character sequence caused WordPress to discard most of the post. One last try, with *less than* spelled out.

    re: #129 F.C.H. #130 Eric

    I *never* said per-capita energy was the whole issue [that's like saying CO2 is the *whole* issue in climate change :-) Since I mentioned efficient-energy I think the end result matters (not just the energy input), and my house has been filled with CFLs for a long time.

    I did say:

    "I’d be happy to have someone read the cited sources and knowledgably explain why they’re wrong … "

    Haven't seen that yet...

    Your examples are rich-world high-tech consumer products, one category of which (computers) is famous for the rapidity of cost-reduction. These have little to do with where this started: "globalization reducing world poverty", because that primarily means reducing rural poverty [63% of those on *less than* $1/day worldwide according to IMF].

    In the USA, 2% of the population are farmers [due to land-grant ag schools, science/breeding, cheap energy, and lately, some help from computing technology]. They produce more food than we need, and some get paid to leave land fallow.

    A 50% cost reduction for compute power helps American farmers … but I bet most would rather get a 50% cost reduction in fertilizer or gasoline. Electronics is good for many things, including saving energy in smart buildings, routing trucks to save fuel, teleconferencing, etc, but it only modestly helps grow food or move things when they really must be moved, for which real energy gets expended.

    Is North American farming (2%, heavily mechanized) is representative of the world?

    John Deere says of farm populations
    4.4% Western Europe
    16.5% Brazil
    53.7% India
    66.6% China

    I’ve occasionally visited (nicer) farm villages in India and China and elsewhere in developing world.

    Some of these people (or a village) may even have a cellphone … which makes them “wealthier” than their parents … but they *still* do hard physical labor all day. How cheap would cars need to get for them to have one?

    But first, maybe a tractor would be good, and energy to run it. Of course low-quality roads are nice – better than none, which is what many have (in Africa, anyway). Unfortunately, building roads takes energy (human, draught, or machinery), for which low-cost consumer electronics may help a little, but not much. I’ve been in villages that had no roads, just footpaths and small boats. One such village did have a VCR+TV, run by a small generator. No cellphones (no signal).

    WHAT IS FARMING LIKE IN MUCH OF WORLD?
    Read “4.6.2 Farm power” FAO (http://www.fao.org/DOCREP/005/Y4252E/y4252e06b.htm) and look at Table 4.16 “proportion of area cultivated by different power sources.”
    (hand, draught animal, tractor)

    “Human labor is the most significant power source through-out sub-Saharan Africa.” (tsetse flies make it hard on draught animals …) and FAO expects that 45% of the land there will still be cultivated by hand in 2030. They do estimate big increases in tractors in many regions, but tractors sometimes require difficult-to-get supporting infrastructure. Of course, there are plenty of crops for which mechanization doesn’t work very well.

    If there’s any mention of “Peak oil” in FAO’s website, I couldn’t find it. For farm mechanization to continue increasing worldwide, we’re going to have to get a whole lot better with solar, wind, miscanthus, jatropha, etc. We can and will, but infrastructure doesn’t change overnight, now matter how fast oil prices go up. People are starting to build electric tractors, which with solar charging may let third-world farmers skip gasoline (that they’re not going to get anyway). http://www.renewables.com/Permaculture/ElectricTractor.htm is interesting.]

    I’m not unfamiliar with the benefits of technology progress in producing more value/energy-input, but rich-world consumer product trajectories don’t relate as much to reducing third-world poverty as do things like building roads, creating better crops tuned to local conditions, no-till farming, lower tariffs, and of course, solving many governance issues.

    re: #130 Eric

    I don’t know if having middle-class Americans’ income stagnate helps solve third-world poverty.

    I do think that Just-in-Time worldwide supply-chains that depend on flying products around from half the world away are in for serious rethinks, but even surface shipping is going to get more expensive (good news for Mexico vs China), and in fact, if transport costs get high enough, I’d expect a lot of manufacturing to disperse again to be closer to its markets.

    “Soaring Oil Prices Will Make the World Rounder”, Oct 19, 2005, in
    research.cibcwm.com/economic_public/download/occ_55.pdf

    “Cheap gasoline in Producing Countries Will Have The Rest of World Paying More”, July 18, 2007:
    research.cibcwm.com/economic_public/download/sjul07.pdf
    If you prefer something shorter:
    http://www.salon.com/tech/htww/2006/01/31/transport/index.html

    “Our per capita energy use is flat despite our economic growth.”
    Well, I’m not sure who “our” is, and I’m not sure what period is implied (for macroeconomic discussions, multiple decades makes sense) but see:
    http://www.data360.org/dsg.aspx?Data_set_Group_Id=1499

    “our” is true, (at least for electricity) since mid-1970s if you are in California (or a few other states), but for the US as a whole:
    1960 ~4 KWh/person (CA same)
    2003 ~12 Kwh/person ( CA flat ~6 since mid-1970s: good news: if you really try hard, you can get more efficient, but it takes persistent effort over decades, with no simple silver bullets. Of course, a mild climate helps.)

    For the world as a whole:
    http://en.wikipedia.org/wiki/World_energy_resources_and_consumption,
    see chart on (Energy Consumption vs GDP)/capita … If energy keeps getting more expensive, the US better figure out how to make a strong left-shift on that chart, because otherwise it’s down-and-left.

    As for developing countries, going to biofuels is certainly a good idea: they can’t afford much oil, and maybe they can just skip that phase (akin to skipping wires for telecom in favor of cellphones).

    Anyway, that data supports what I said. I’ll happily look at contradictory *data*.
    ========
    This may be getting further OT for RC, but really, one has to bring the same kind of analysis (numbers, relevant facts, cites) to the problem.
    Like I said:
    “vague assumptions about globalization and increased wealth aren’t very convincing.”

    Comment by John Mashey — 26 Aug 2007 @ 3:28 PM

  148. Re 146: the only way you can replicate the role of snowpack with dams is if, and only if, rain patterns will change in such a way to allow compensation. If there is no rain to be stored in order to compensate for the snow that was not there to melt in the first place, dams are useless.

    Comment by Philippe Chantreau — 26 Aug 2007 @ 3:53 PM

  149. John, don’t want to trivialize your excellent post (148), but it brought back a very distant memory from 30-40 years back. An auto manufacturer (Chrysler maybe) came up with a plan to produce a bare-bones very small but useful cheap farm vehicle for the Indian market (then). Something that could be bought for a few months average income and almost double productivity (their estimate — and my memory is pretty fuzzy). They were disallowed by our gov’t because it didn’t have many (none?) nice aux safety features like seat belts.

    Comment by Rod B — 26 Aug 2007 @ 10:09 PM

  150. but it brought back a very distant memory from 30-40 years back.

    Distant, and inaccurate, since the feds can only regulate vehicles sold domestically.

    Comment by dhogaza — 26 Aug 2007 @ 11:54 PM

  151. John (#148), I don’t who data360 is, but their numbers are off. The economist article that they link to doesn’t contain the numbers they claim. The numbers are flat, see for example: http://www.eia.doe.gov/emeu/25opec/sld020.htm Over that same period our economic growth was about 70%. I agree with your ideas on farming. In general the US pays farmers without consideration to self sufficiency or energy usage. Perhaps you thought I implied cause and effect for globalization. It is that increasing incomes for the poorest of the poor leads to stagnating incomes for the rich (i.e. middle class Americans), as fallout from a more efficient division of labor.

    Comment by Eric (skeptic) — 27 Aug 2007 @ 5:54 AM

  152. take a look at the papers linked to at http://climate.envsci.rutgers.edu/nuclear/, and particularly at:

    NUCLEAR WINTER REVISITED WITH A MODERN CLIMATE
    MODEL AND CURRENT NUCLEAR ARSENALS:
    Re #125 [re 121

    The nuclear winter scenario involves the nuclear destruction of cities, and consequently large amounts of soot lofted into the stratosphere. Individual nuclear tests don’t generally do that. You got some of it with Hiroshima and Nagasaki, but not enough to be significant.

    =============

    I recall reading recently that the amount of particulate matter tossed up in the atmosphere by Krakatoa in 1883 was along the order of 13,000 times that of Little Boy…]

    The attacks on Hiroshima and Nagasaki did not cause firestorms. In a modern nuclear war, using many much more powerful weapons, if cities were targeted a considerable number of firestorms are almost inevitable. These would loft large amounts of black carbon into the stratosphere, where it would remain for years to decades. I’ve no idea whether your figure for Krakatoa is accurate, but the nature of the particulate matter would have been completely different. In a discussion in April this year, I posted the following:

    [Take a look at the papers linked from http://climate.envsci.rutgers.edu/nuclear/
    especially:

    STILL CATASTROPHIC CONSEQUENCES
    Alan Robock, Luke Oman, and Georgiy L. Stenchikov (J. Geophys. Res, in press)

    This indicates that global nuclear war would have utterly devastating atmospheric and climatic effects - global dimming and cooling (to mean temperatures below that at the LGM 18000 years ago)and a sharp drop in precipitation, largely wiping out agricultural production for perhaps a decade, plus extensive destruction of the ozone layer. Still, at least we wouldn’t need to worry about AGW any more.]

    Comment by Nick Gotts — 27 Aug 2007 @ 7:06 AM

  153. Re #152 Sorry, my last got rather garbled – please ignore everything before “Re #125″.

    Comment by Nick Gotts — 27 Aug 2007 @ 7:08 AM

  154. Nick, fact check: http://www.atomicarchive.com/Effects/effects11.shtml
    ———— begin excerpt ————
    Firestorms

    Under some conditions, the many individual fires created by a nuclear explosion can coalesce into one massive fire known as a “firestorm.” The combination of many smaller fires heats the air and causes winds of hurricane strength directed inward toward the fire, which in turn fan the flames. For a firestorm to develop:

    * There must be at least 8 pounds of combustibles per square foot.
    * At least one-half of the structures in the area are on fire simultaneously.
    * There is initially a wind of less than 8 miles per hour.
    * The burning area is at least 0.5 square miles.

    In Hiroshima, a firestorm did develop and about 4.4 square miles were destroyed. Although there was some damage from uncontrolled fires at Nagasaki, a firestorm did not develop. One reason for this was the difference in the terrain. Hiroshima is relatively flat, while Nagasaki has uneven terrain.
    http://www.atomicarchive.com/Effects/Images/WE09.jpg
    Firestorms can also be caused by conventional bombing. During World War II, the cities of Dresden, Hamburg, and Tokyo all suffered the effects of firestorms.

    Comment by Hank Roberts — 27 Aug 2007 @ 8:24 AM

  155. > Eric 27 August 2007 at 5:54 AM
    You’re comparing kilowatt hours to british thermal units there, and different time spans, but the charts don’t look inconsistent. I emailed the data360 guy, maybe he’ll check in.

    Comment by Hank Roberts — 27 Aug 2007 @ 9:04 AM

  156. If ensembles cannot be used to create probability distributions, and thus likelihoods of particular outcomes, as Gavin argues here, then I presume their use must be for evaluation against empirical data, in order to determine that same likelihood. Can anybody clarify the main purpose of running ensembles?

    [Response: Most ensembles are 'initial conditions' ensembles and are performed to average out 'weather' to get to the forced response. The perturbed parameter ensembles, I think, are useful in exploring phase space and finding good solutions that might not otherwise have been found, but whether they can be usefully averaged to get robust results is still being explored. - gavin]

    Comment by Jim Bouldin — 27 Aug 2007 @ 10:39 AM

  157. The feds, dhogaza, can regulate almost anything manufactured within the US, regardless where sold. Also, sometimes the regulation is quite successful arm-twisting and extortion rather than legal code based. [edit]
    (maybe I can sneak this past Gavin …[;-) [nope - G.]

    Comment by Rod B — 27 Aug 2007 @ 11:23 AM

  158. Re #154 Hank, thanks for the correction. All: apologies, I relied on memory in saying that there was no firestorm at Hiroshima, and it let me down.

    Comment by Nick Gotts — 27 Aug 2007 @ 11:30 AM

  159. Re #147: [...but they *still* do hard physical labor all day.]

    Whereas I, having the advantage of living in a technological civilization (and being, if you’ll forgive the immodesty, amongst the technical elite), sit at a desk all day, then spend most of my evenings doing hard physical exercise to compensate for the effects of that sitting. Forgive me if I fail to see that the benefits are quite so one-sided as you imply :-)

    This seems to reflect on a broader philospohical question. People tend to discuss wealth in connection to AGW and various mitigation options, but what exactly is it? Just having more money? But how if the price of those goods you want increase even faster than your income? Am I getting richer, because I can afford more consumer goods (most of which I don’t want), or poorer, because the world has changed in such a way that I’m less able to afford what I do want?

    Comment by James — 27 Aug 2007 @ 12:23 PM

  160. Re: #147

    John –

    My use of computers as an example was because you and I are both in that industry. However, there are advances in technology that are outside of the computer biz.

    Sticking strictly with “energy”, since that’s where you are focusing, 100% renewable power is falling below the costs of non-renewable, for example solar concentrating photovoltaics — http://www.solar.unlv.edu/amonix_system.php . Parabolic reflectors can be used as well, and simpler single axis automatic trackers can be used, rather than the two axis variety used by Amonix. This is an example of technological advanced produced wealth.

    It is the nature of technological advancement that there aren’t a lot of hard numbers. For example, until the first super-scalar processors were made, it was considered impossible to issue more than one instruction per cycle. My recollection is that Gene Amdahl (and now I’m way into geek history) is the source of that “rule”. I don’t know anyone who thought phone modems would ever exceed 9,600 bps, and a number of us were absolutely amazed when Telebit introduced the “Trailblazer” line of equipment. The last modem I bought, before getting broadband, was capable of 118,000 bps on an ordinary phone line.

    Non-geek examples: Airplanes were supposed to be impossible. The electric starter for the automobile — impossible. Space flight — impossible. Each of these problems was solved by technology of some sort or another and there is simply no evidence that “energy” won’t also be solved by technology.

    Comment by FurryCatHerder — 27 Aug 2007 @ 1:53 PM

  161. “Each of these problems was solved by technology of some sort or another and there is simply no evidence that “energy” won’t also be solved by technology.”

    On the other hand, “perpetual motion” is a problem that was not solved by technology, and hoping that technology will “solve” it, is not that good a bet.

    You see, there is this small matter of thermodynamics. And, oddly enough, any time you are going to play with large amounts of energy, thermodynamics gets to be the referee.

    Comment by Andrew — 27 Aug 2007 @ 2:16 PM

  162. re: #151 Eric

    Thanks for the useful pointer, in fact, it is well worth reading the whole presentation,www.eia.doe.gov/emeu/25opec/sld000.htm, even though it is 10 years old, and has some “amusing” elements, such as slide 4, showing the price of gasoline, with a horrific peak around 1982 or ~$2, before subsiding again to its nice stable price ~$1.20 :-) It’s well worth looking at different ways to slice all this, but I do urge you to read the economics references I gave back in #127.

    Note that per capita use of energy declined over 25 years, because after the OPEC embargo, there was more emphasis on efficiency. The chart notes that since 1983, energy use has increased at 0.8 percent per year. Efficiency always matters, and of course, there are big differences in GDP/energy consumption by the economic mix: one would expect areas with big software companies to have high GDP/energy, for instance.

    Here are a few more interesting graphs:
    http://www.fi.edu/guide/hughes/topic5.html
    http://www.nationmaster.com/graph/ene_usa_per_per-energy-usage-per-person

    http://www.eia.doe.gov/emeu/cabs/carbonemiss/chapter4.html is especially useful, since it describes/compares Asian economies in various phases of usage, showing that both energy supply & efficiency matter.

    re: #159 james
    I’d never say the benefits are one-sided; I grew up on a small family farm, and there are many merits to that [outdoors, early responsibility, learn about ecology/sustainability before you're 10, parents do comprehensible work that you can actually help with, more coherent community relationships, and some people really love the independence of running their own business.]

    Nevertheless, it’s hard work, bad weather can wipe you out, and (especially with livestock) it never stops. Unsurprisingly, a lot of farm kids decide they’d rather do something else.

    I’ve often seen urbanites rhapsodize about how nice it would be to have a farm in the country, and for some people, that’s a good move. I’ve heard people talk about spending a wonderful week, say on a Swiss farm. My suggestion is, before you buy one, try it for a year, *for real*, and make sure you like it.

    A lot of people in rich countries really don’t understand how food happens. [My favorite was a NYC guy at grad school with me, whose only office decoration was a NYC subway map. He liked chocolate milk, so we took him to the Penn State fields to show him the dark cows that gave it... He wasn't sure we were joking. How was he to know? He'd never gotten his milk by milking a cow, but by going to the store.]

    There are also big differences among:

    1) First-world farms, embedded in high-tech societies with good transport and communication. [Even *I* might like a week on a Swiss farm].

    2) Developing-world farms [like some of those India & China ones], organized around cooperative villages. Compared to 3), these are incredibly prosperous. However, in China, you may have noticed that many people have been leaving their lovely villages for “better prospects” in coastal manufacturing, whose conditions would not thrill many.

    3) Real third-world subsistence farms, say in sub-Saharan Africa.
    ====
    Exactly what wealth is, I don’t know. The economists I referenced use specific definitions for production, but that isn’t necessarily wealth.
    However, I suspect a typical Kansas farmer would be viewed as unimaginably wealthy by most Chinese farmers…

    Comment by John Mashey — 27 Aug 2007 @ 2:22 PM

  163. Hank (#155), thanks, I knew the units were different, but the trend should be the same. John (#162), I downloaded and read “reintegrate” and I’ll get to the rest soon. Interesting perspective, I always thought that more integrated models would be a good answer to get common ground on policy issues. It would help prevent political debacles like ethanol and get people thinking about ways they can reduce their waste they would have never thought of.

    Comment by Eric (skeptic) — 27 Aug 2007 @ 7:10 PM

  164. [[Airplanes were supposed to be impossible. The electric starter for the automobile — impossible. Space flight — impossible.]]

    None of the arguments against these depended on physical principles; they were arguments about engineering. Heavier than air flight is obviously possible, since birds do it. But using a steam engine you couldn’t build an airplane light enough. The arguments against space travel were just wrong, and could be shown to be wrong ever since Newton published the Principia.

    Comment by Barton Paul Levenson — 28 Aug 2007 @ 5:42 AM

  165. Re 141:

    Andrew writes:

    On the other hand, “perpetual motion” is a problem that was not solved by technology, and hoping that technology will “solve” it, is not that good a bet.

    You see, there is this small matter of thermodynamics. And, oddly enough, any time you are going to play with large amounts of energy, thermodynamics gets to be the referee.

    There is nothing about our current energy consumption that cannot be solved because it violates any of the laws of thermodynamics. All of the electricity requirements of the 120 homes that make up my neighborhood can be satisfied on the currently unused land within my neighborhood. The subdivision east of me, which I think is about 2,000 homes is the same way.

    The obstacles aren’t physics, they are things like “I don’t want to use those lights because then I can’t use my dimmer”, or “I don’t want to see a wind turbine in my neighborhood”.

    Comment by FurryCatHerder — 28 Aug 2007 @ 9:22 AM

  166. Re #164:

    None of the arguments against these depended on physical principles; they were arguments about engineering.

    And all the arguments against what myself and others have said are likewise not about physical principles, they are based on politics, economics, personal nature, or just plain crankiness.

    It’s like American car companies — they claim they can’t build fuel efficient cars, but other countries have been doing it for years, have higher corporate fuel economies, and seem to stomp our butts in the marketplace. Quit it with the excuses, already.

    Comment by FurryCatHerder — 31 Aug 2007 @ 3:11 PM

  167. “The mathematical physicist v. Neumann once said to his young collaborators: ‘If you allow me four free parameters I can build a
    mathematical model that describes exactly everything that an elephant can do. If you allow me a fifth free parameter, the model I build will forecast what the elephant will say.’

    Isn’t the same problem that portrays relying on Climate Modeling as predictors?”

    I don’t think von Neumann said that, it’s a very old story with many forms. And, of course, if you think like an early twentieth century engineer, you might believe it. But it’s obviously false. No mammalian genome can be accurately described with a small number of parameters, so that anecdote should be retired.

    More to the point in climate, an early attempt to approach the number of parameters required for atmospheric prediction is Ed Lorenz’ work on “analogs” (Lorenz, E. N., 1969: Atmospheric predictability as revealed by naturally occurring analogues. J. Atmos. Sci., 26, 636–646) and you get a lower bound on the number of parameters of about 500. Yes, when you go from weather to climate you average a lot of stuff out, but it’s going to be tough to whittle that down to the proverbial 6 parameter charging rhinoceros.

    Many fields now routinely confront problems with thousands of parameters. This is the twenty first century. If, for example, we consider a less politically charged subject, say wine making. These guys (http://dynopt.cheme.cmu.edu/papers/preprint/paper19.pdf) are working with over 33,000 variables. That’s not even that big compared to other complex systems.

    The bottom line is that yes, it is the same for climate modelers – they have a lot of variables and they have to take some care of that. But it’s the same as for a lot of fields these days, you can take appropriate care, and get good results. The fact that there are a lot of parameters does not mean that models will not perform well.

    Comment by Andrew — 6 Sep 2007 @ 3:40 PM

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