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Climate Change Commitment II

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

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


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

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

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

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

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


727 Responses to “Climate Change Commitment II”

  1. 101
    Rod B says:

    Ray Ladbury, “…well known and irrefutable…” ??!!? Man! You’re easy — at least when in your favor. Why wasn’t Greenland the center of the industrial revolution? You’re probably correct in pooh-poohing the idea that warming will greatly improve things (at least beyond some point) but that doesn’t warrant your hyperbole.

  2. 102
    Leonard Evens says:

    Edward Greisch says :

    “79 Leonard Evens: Putting poison gas in the stratosphere is not the right kind of geo-engineering.”

    Having just given three reasons why the use of aerosols was problematic, I am surprised that anyone would think I was advocating it. As an afterthought I did remark that at some time in the future, as a desperate measure, some method of geonegineering might be considered. But it makes much more sense to limit emissions today, so we don’t have to worry about choosing among highly questionable approaches, the side effects of which would be likely to be unknown.

    Actually, the only `geoengineering’ approach which it seems to me might possibly work is to remove CO_2 from the atmosphere directly, which seems to have developed some advocates. But I suspect it would be very expensive and not all that effective. Again, I say the obvious. Let’s just limit emissions by switching to non fossil fule based energy sources. The main argument against doing that is that it would be more expensive. But, were the eventual costs of the use of fossil fuels figured into their cost, the calculus would be different.

  3. 103
    Ray Ladbury says:

    Rod, I’m saying that the correlation is irrefutable. I said nothing about cause or effect. I’ll stand by that unless you have some alternative math I don’t know about.

  4. 104

    Umm, sorry about the bad link I posted way back there. . . somewhere. (Tried using the “search” function to locate the exact comment, but no joy.)

    I’d said I was linking to “the state of the science in 1938″–but inadvertently linked instead to my article on Ekholm, which gives the state of the science in 1901.

    G.S. Callendar was the 1938 author, of course, and the correct link is here:

    http://hubpages.com/hub/Global-Warming-Science-And-The-Wars

    Thanks–and apologies for any confusion and/or annoyance to those following the link.

    (Author totters off, muttering unintelligibly.)

  5. 105
    Rod B says:

    BPL, your (and many others) bar for defining a “mature” science is really low. Doesn’t take much

  6. 106
    Rod B says:

    Ray Ladbury, so, if “…the correlation is irrefutable…” [my emphasis] what does this have to do with anything??

  7. 107
    Hank Roberts says:

    > you can’t have at the same time a GDP decrease with temperature,
    > and a GDP increase with temperature.

    Sure you can. Try adding “plus six” to “minus three” for example.

  8. 108
    Neil B says:

    I would really like some answers on this: increase in average temperatures, in variability etc. is important but what about dew points? I am sure average dew points are much higher here in SE VA in the summer. But I don’t see data. Increased evaporation can add IR absorbing CO2 to the air, but also promote cooling. That might ameliorate the temperature increase, but high dew points cause their own problems (more mold in houses etc.) and are uncomfortable. Is anyone looking at this, please?

  9. 109
    Neil B says:

    @84, you are so wrong. For one thing, you have no grounds to deem such societies (which, BTW?) as “sustainable” since you don’t know how much longer they’ll continue current SOL. How about oil supply falling or getting so expensive to extract, while demand increases or fails to adapt? And the blind faith in technology is absurd. Technical progress can help but still needs raw materials, energy; has by products etc. Above all, it is not a specific predictable amelioration, it is full of uncertainties and that’s just what will bite us in the ass.

    It would be better to play it safe with push back against population growth, with true sustainables like solar that don’t need supplies that run out or come from nations we have problems with, etc. Finally, I am tired of actually subsidizing population growth through child tax credits awarded (more by Republican policies) up towards 100k family income. Any libertarian types here can’t possible be OK with that. To be consistent, you would have to believe in letting children be a personal cost decision to weigh like everything else.

  10. 110
    Completely Fed Up says:

    “Why wasn’t Greenland the center of the industrial revolution?”

    Why industrial? Why not the Renaissance (Holland)? Or agricultural (Ur)? Or scientific (Greece)? Or practical (China)? If we’d found them earlier, we’d probably have a revolution of civilisation from the New World too.

    PS the reason is because the UK had the industrial revolution. Part of this is that you need a large power base and Greenland doesn’t have one.

    It’s funny how you’re all over single attribution when someone else does it, but silent as the grave when you or another denialist does this.

  11. 111
    Benjamin says:

    @Ray Ladbury
    “I’m not seeing anything in that reference that could even be misinterpreted as supporting your point.”
    The “climate catastrophe” scenario shows a constant GDP growth of 3% as shown in the reference(=x26GDP), which to my knowledge is not a GDP decrease.

    @Bob Sphaerica
    “Obviously, temperature change is not the only factor that affects GDP”
    Good observation. I agree with that.
    Moreover, i would say that as up to now, climate and GPD change are uncorrelated.

    “A 1C temperature increase reduces GDP by 1.1% of what it would have been without the temperature increase.”
    “using an annual growth rate somewhere around 2.2% to 3%, so climate change is potentially going to cut growth, annually, by one third to one half (until the wheels come off).”

    Well no, that’s not correct.
    The annual projected growth is +3% in the catastrophe scenario, we agree on that.
    Now you’re saying we have -1.1% every time we get +1°C.
    But we don’t get +1°C every year : roughly in the +6°C scenario we would get it every 15yrs.
    You still get a x20 GDP !!!!!

    “They could not and did not perform the recursive task of then shrinking GDP as an effect of the instigated, projected climate change.”
    Well, isn’t that basic modeling 101 to get a viable projecton to take into account a feedback ?
    Either the feedback is negligible, and you dont take it into account, or it’s a first order feedback and then you have to take it into account ! Otherwise the projection is totally useless.

    “that doesn’t even count the fact that there simply isn’t that much fossil fuel to burn, so the supply will be cut off long before we wean ourselves of the addiction.”
    Are you saying that the number they used in “fossil fuel reserves” are wrong too ?
    I mean that would be grotesque, fossil fuels = CO2. If you put random fossil fuels numbers, you get radom CO2 emissions and the scenarios are nowhere near realistic scenarios.

    I mean the entire world will be looking at those scenarios and see the +6°C.
    Wouldn’t it be just normal to add a little comment next to it saying “Not only are those high range scenarios unrealistic in terms of fossil fuels reserves and CO2 emissions, they also lead to a multiplication by about 20 of the GDP which means that Bangladesh will basically have current US standard of living by then so life for them should be pretty comfortable”

  12. 112

    101 (Rod B),

    Why wasn’t Greenland the center of the industrial revolution?

    What you have said equates to “If a harsh climate will cause increased development, then the harshest climate should cause the most development, and if not, then the entire premise is false,” which is clearly an absurd line of reasoning (i.e. it ignores all other factors, such as total population, resource availability, and a threshold beyond which a harsh climate becomes too much of a hindrance rather than merely an incentive).

  13. 113
    SecularAnimist says:

    “Geoengineering” as the term is usually used, is an absurdity.

    There is NO evidence — none, zero, zilch — that human beings have the knowledge, understanding or means to “engineer” the Earth’s climate and biosphere to achieve some particular desired outcome. On the other hand, there is PLENTY of evidence that we have the ignorance and hubris to wreck the Earth’s climate and biosphere, as we are currently doing.

    Talk of adding huge amounts of toxic pollution to the Earth’s atmosphere to offset AGW is just plain stupid. Talk about “ideology” — that is the exact kind of “ideology” that got us in the mess we are in now. Not to mention that there is no reason to believe it would work, and plenty of reasons to believe it could make things much worse.

    Having said that, there is also plenty of evidence that we can change our ways so as to allow, and even help, natural processes draw down the anthropogenic excess of CO2 — specifically, by a massive conversion to organic agriculture techniques and an equally massive global reforestation program, to sequester CO2 in the soil and biosphere.

    We can draw down the excess CO2 by helping to make the biosphere healthier — not by poisoning it even more than we already are with some kind of hare-brained “geoengineering” scheme.

  14. 114
    Journeyman says:

    This is interesting. Has any followup work been done. For example, if you stop emitting in 2020 under different emissions scenarios, how much do these curves change? This is the real cost of inaction.

  15. 115
    Completely Fed Up says:

    “Ray Ladbury, so, if “…the correlation is irrefutable…” [my emphasis] what does this have to do with anything??”

    Why if something is irrefutable, can you refuse to accept it? Wouldn’t that be refuting the process by personal preference alone?

    Ah, sorry, forgot who I was talking to.

    SOP, Rod.

  16. 116
    Jim Eager says:

    Benjamin gets just plain silly @111:

    “Wouldn’t it be just normal to add a little comment next to it saying “Not only are those high range scenarios unrealistic in terms of fossil fuels reserves and CO2 emissions, they also lead to a multiplication by about 20 of the GDP which means that Bangladesh will basically have current US standard of living by then so life for them should be pretty comfortable”

    since most of Bangladesh will long since be under water by the time we see a +6C increase, regardless of their GDP.

    He also assumes that fossil fuels are the only potential reservoir that could push temperature up by +6C, when in fact we are likely see carbon emissions from terrestrial and continental shelf seabed carbon reservoirs begin to dwarf human emissions somewhere around +4C to +5C.

    Get a grip, Benjamin.

  17. 117
    Septic Matthew says:

    73, Ray Ladbury: Rod B, all I have done is call attention to a well known and irrefutable inverse correlation between higher temperature and wealth and economic growth. This is hardly controversial, and it holds quite broadly.

    Are you sure that’s well known, irrefutable, and holds broadly? In the 15th century economic growth was greater in Italy and Spain than in (what is now) Great Britain, but in the 19th century it was greater in Great Britain than in Italy and Spain. 100 years ago economic growth was greater in Great Britain than in China, but now it is greater in China than in Great Britain. Within China, at various times, economic growth has sometimes been greater in the north near Beijing, and sometimes (like since 1975) greater in the south near Hong Kong. In the 700s economic growth was greater in Baghdad and Damascus than in Paris, London and Berlin, but since 1550 or so the relative growth rates have reversed. At the time the Khmer civilization produced its most rapid economic growth, almost all of the cooler regions of Asia had stagnation. About the only real generalization relating temperature to growth is that economic growth has never been very great at high latitudes where even summer is too cold for plentiful crops. Economies have grown and shrunk in the same climate (most examples of growth and decline), with rainfall (in Central America, and the area inhabited by the Anasazi) and culture (including changes within nominally the “same” culture, as with China) being more important than temperature, and of those culture being predominant.

    The developed world is right now investing more rapidly in non-fossil fuel energy supplies than in fossil fuel energy supplies, and is sharing some of the new technologies with the less-developed world. If present rates of non-fossil fuel technology development and deployment persist, what do you think is the most likely scenario for global temperature change and GDP change in the next decade? Next 4 decades?

    Fossil fuels will continue to increase in price as demand increases or stabilizes, because supplies are diminishing, and what remains is increasingly more costly to extract. Non fossil fuel costs continue to decrease as the technologies are improved and mass produced. When those trend lines cross, business as usual will without subsidies shift greater amounts of investment into non-fossil fuel development. No one knows when that will be (every year there is a new forecast for PV solar that it will be within the next 2 years — I read one such just day before yesterday), but with recent developments I shall be surprised if it has not happened by 2010.

  18. 118
    Septic Matthew says:

    1, Bob (Sphaerica): I’d be very interested in seeing a study presenting a variety of realistic, feasible scenarios that take into account such factors as oil resource limitations (i.e. what if we really do hit peak oil in 3-4 years?) and the subsequent economic impacts — positive feedbacks on fossil fuel reductions, if you will (i.e. if fossil fuel supply drops precipitously, then disturbances in economies would reduce usage even beyond supply changes).

    Me too. What if, instead of increasing or decreasing, the rate of fossil fuel production stays nearly constant over the next 10 years or more? Statistics presented at The Oil Drum make it seem that oil production has been constant over the last 6 years, despite a large increase in the international price. Production has been maintained by drilling deeper (as the BP disaster has alerted everyone who did not already know) and in other ways spending more per each barrel extracted.

  19. 119
    Anonymous Coward says:

    #113
    “There is NO evidence — none, zero, zilch — that human beings have the knowledge, understanding or means to “engineer” the Earth’s climate and biosphere to achieve some particular desired outcome.”
    but
    “We can draw down the excess CO2 by helping to make the biosphere healthier”

  20. 120

    111 (Benjamin),

    Now you’re saying we have -1.1% every time we get +1°C.
    But we don’t get +1°C every year : roughly in the +6°C scenario we would get it every 15yrs.
    You still get a x20 GDP !!!!!

    No. The statement is not that “a 1˚C increase reduces GDP by 1.1% the year that it happens.” The statement is “for every 1˚C anomaly, there is a 1.1% reduction in annual GDP.” The theory is not that temperatures will go up, and then back down. The theory is that GHG will raise temperatures for the long term. The anomaly will remain, year after year, with the same detrimental effects, year after year.

    Well, isn’t that basic modeling 101 to get a viable projecton to take into account a feedback ?

    Think about it. What was the point of the original exercise? What steps must be done to estimate actual climate change resulting from each scenario? To what degree of accuracy do you get projections? What steps must be performed to then project adjustments to GDP resulting from climate change? What other factors might be involved? What is the point of having several scenarios, and what differences do those scenarios reflect? Is what you are asking/expecting at all reasonable?

  21. 121
    Doug Bostrom says:

    Neil B says: 4 June 2010 at 10:22 AM

    I’m not sure I got your question exactly, but evaporation at the surface won’t get rid of energy at the top of the atmosphere, where it needs to emerge and leave in order to keep things reasonably cool. Plus of course water vapor in the air is a GHG itself.

    Regarding dewpoints this item is of interest, thinking from the perspective of comfort etc.:

    http://www.skepticalscience.com/Heat-stress-setting-an-upper-limit-on-what-we-can-adapt-to.html

  22. 122
    Completely Fed Up says:

    AC (#119), please read SA’s opening definition of geoengineering:

    ““Geoengineering” as the term is usually used, is an absurdity.”

    Geoengineering as the term is usually used doesn’t include reducing CO2 and increasing natural draw down. It’s usually “pour SO2 sprays into the air and hope that this works” or similar “big engineering” projects.

  23. 123
    Benjamin says:

    @Jim Eager
    “since most of Bangladesh will long since be under water by the time we see a +6C increase, regardless of their GDP.”
    That’s not what recent “in situ” studies indicate :
    http://www.google.com/hostednews/afp/article/ALeqM5jxWAlO7hpr2AXkrZMWswKyK39gOA

    And by the way, relocating hundred of millions of people or building hundred of kilometers of dikes over a century is not a problem AT ALL. We could build houses for more than 4 billion people of the XXth century. Global population is predicted to rise to 9 billion so that about +2.5billion people. So just with XXth techniques/knowledge/”richness” we could build houses for 1.5billion people or “refugees”.

    “He also assumes that fossil fuels are the only potential reservoir that could push temperature up by +6C”
    Nope, i’m just using SRES scenarios to say this….

    “when in fact we are likely see carbon emissions from terrestrial and continental shelf seabed carbon reservoirs begin to dwarf human emissions somewhere around +4C to +5C.”
    World GDP would already be multiplied by 10 or 15, what’s the problem then ?

  24. 124
    Martin Vermeer says:

    Shorter Anonymous Coward #115:

    “You claim geo-engineering is crazy, BUT rolling back the on-going unplanned geo-engineering is un-crazy. Contradiction.”

    What contradiction? I see consistency.

  25. 125
    Benjamin says:

    @ Bob Sphaerica
    “No. [...] The statement is “for every 1˚C anomaly, there is a 1.1% reduction in annual GDP.””
    Ok but
    1/ That’s not backed up by any historical data or any data at all
    2/ That’s not very likely … at least for the first 50 yrs or so. Current warming rate is about 0.15C/decade. Even if this doubles every decade, we get the first degree increase from now (where no effect of global warming on economy can be seen) only in … 30yrs.
    3/ that is in contradiction with all SRES scenarios.

    “Think about it. ”
    The questions you are asking me are exactly the questions i would like to ask :
    * What’s the point of unrealistic scenratios ?
    * Are they based on realistic fossil fuels reserves (you seemed to suggest that this is not the case).

    “Is what you are asking/expecting at all reasonable?”
    A model where you add a feedback of temperature on GDP is “more than easy” to do…
    Just to give you an example in 1970′s people could already to whole world simulations with a wide range of forcing/feedbacks (World3 model for example http://en.wikipedia.org/wiki/World3).

  26. 126
    Edward Greisch says:

    To everybody who is arguing over GDP vs climate: The way climate interacts with GDP is through agriculture. Workers work the hardest when they are well fed. They don’t work at all when they are not fed. What farmers need is a STABLE climate and a climate that is THE WAY IT WAS when farmers began growing that crop in that place. Sure, you can say GDP went up when “bad” weather went away and the weather returned to “normal,” but “bad” can mean wetter or dryer or hotter or colder or it rained the right amount but at the wrong time.
    Your extrapolations in any direction are wrong because they are away from stability. The best thing for agriculture here in the middle of the US would be to put the climate back the way it was in the 1950s because the 1950s is a sort of standard for ~1830 to ~1980 when farming was good. Caveat caveat caveat. The climate is becoming less stable and that is bad for agriculture.

  27. 127
    Benjamin says:

    @Edward Greisch
    “The best thing for agriculture here in the middle of the US would be to put the climate back the way it was in the 1950s because the 1950s is a sort of standard for ~1830 to ~1980 when farming was good. ”
    Now that’s weird.
    Between the 1940′s and 2000′s U.S. agricultural output more than tripled, while the United States Department of Agriculture’s (USDA) index of aggregate inputs (land, labor, capital and other material inputs) remained essentially unchanged.
    http://www.ers.usda.gov/AmberWaves/September08/DataFeature/Charts/DataFeature_fig01.gif

    If this is going away from an optimum, then i don’t understand what an optimum is.

  28. 128
    Ike Solem says:

    Colin Crawford says:

    “Moreover, the research into permafrost thaw/retreat and associated increases in methane release I’ve been reading over the past couple years indicate that that process is accelerating at an “unanticipated” degree. Given the serious under-estimations (in the IPCC reports) of Arctic ice retreat witnessed over the past half-decade or so, I think it’s more “realistic” to assume that there will be a greater and sooner “contribution” to global (especially Arctic) warming than is currently expected. In other words, I find it perfectly reasonable to consider that even IF all anthropogenic GHGs did cease “today,” there is sufficient warming-momentum to expect a release of at least 10% of the CO2, CH4 and NOx from that region which, by my calculations, send global CO2-equivalent concentrations above (maybe WELL above) 500 ppm…”

    That seems correct. Why neglect the carbon cycle feedbacks (which are very difficult to model) in their calculation of global warming commitment?

  29. 129
    Jim Eager says:

    You really should read the articles you cite before you link to them, Benjamin. No where in it is there mention of any measurement of warming, let alone a +6C rise in average surface temperature, and it only talks about the impact of a sea level rise of 1 meter on the coast of Bangladesh, yet up to two meters of rise this century can not be ruled out.

    If you think +6C would ultimately produce a sea level rise of only 1 meter you must be smoking something. The last time average surface temperature was 6C higher than today was before both Greenland and Antarctica froze over, which means sea level was around 70 meters (~228 feet) higher than it is today.

    Note that I am not putting a time span on that total melt. That’s because we don’t know how high CO2e will ultimately go and how long it will remain at peak concentration.

    And if you think coping with an earth 6C warmer than it is now think again. GDP will be zero at +6C.

    Try getting a better grip on the science than you have on economics.

  30. 130

    Rod 105: BPL, your (and many others) bar for defining a “mature” science is really low. Doesn’t take much

    BPL: No, just a consistent theoretical framework, professional journals, people working full-time on the issues in that field, a huge database of measurements, and a lively debate over legitimate theories–all of which were present in climate science by 1900 or so.

  31. 131
    t_p_hamilton says:

    Benjamin said:”Between the 1940’s and 2000’s U.S. agricultural output more than tripled, while the United States Department of Agriculture’s (USDA) index of aggregate inputs (land, labor, capital and other material inputs) remained essentially unchanged.”
    “If this is going away from an optimum, then i don’t understand what an optimum is.”

    So the climate must be 3 times better for farming now? I think Benjamin is missing the obvious – is there no argument so ridiculous a skeptic won’t use it?

    PS that was a rhetorical question.

  32. 132
    Witgren says:

    “123Benjamin says:
    4 June 2010 at 2:03 PM

    And by the way, relocating hundred of millions of people or building hundred of kilometers of dikes over a century is not a problem AT ALL. We could build houses for more than 4 billion people of the XXth century. Global population is predicted to rise to 9 billion so that about +2.5billion people. So just with XXth techniques/knowledge/”richness” we could build houses for 1.5billion people or “refugees”.”

    Um, yes, there is a major problem, actually several:

    1) building homes for hundreds of millions of people or hundreds of kilometers of dikes will take both resources and funding. This stuff will not build itself for free. Who pays for it, and how?

    2) If I own a beach house in Florida that is worth a million dollars today but is worthless when the sea level rises and takes it, that’s a loss of assets. Maybe I can absorb it, maybe not. Same with people that have other homes, maybe worth a lot less, but still it is an asset that now is worthless and they have to cope with that loss of assets. And not only have they lost their home, they now have to find a new one (see #1). Are you going to build them a house for free?

    3) Where do you put these people? Where do you find the land to put them? Do you take agricultural land out of production for development? Do you let developers ramp up land prices and take advantage of desperate people? Do you build tar-paper tenements and move them all into overcrowded shantytowns? And again, who pays for it all? The displaced?

  33. 133
    Witgren says:

    Benjamin, the reason US ag output increased because of great leaps in mechanization (how many farms were still using horse-drawn equipment in 1930 versus 1960?), coupled with massive use of commercial fertilizers, pesticides and herbicides. The mechanization allowed many more acres to be opened up to cultivation by a given farmer, and the chemicals allowed him to greatly increase yields, giving outstanding yields on good ground and allowing for decent yields even on formerly marginal ground (and so even more acres went under the plow).

    Third, there have been massive advances in genetics that have increased yields as well. We’ve come up with insect and disease resistant crops, crops that produce greater yields per plant.

  34. 134
    Benjamin says:

    @t_p_hamilton
    I’m sorry i’m not the one coming here saying that agrilcture optimum was in 1950′s when data indicates otherwise….

    @JimEager
    “And if you think coping with an earth 6C warmer than it is now think again. GDP will be zero at +6C.”
    I’m sorry but I trust the IPCC scenarios and the +6°C scenario goes with x24GDP.
    You don’ believe the IPCC numbers ? Are u a climate denier ?
    Would you say that those projections are wrong ?

  35. 135

    125 (Benjamin),

    Ok but

    Typical denier approach. Move the goalposts.

    The questions you are asking me are exactly the questions i would like to ask

    More of the same. Instead of responding, bob and weave.

    Clearly, you’ve latched onto one piece of data (GDP growth projections, used as a foundation for emissions scenarios fed into GCMs) and decided that it’s the answer to everything (“look, the IPCC says civilization is going to thrive! It says so right here, so everything else must be inconsequential!”).

    Hence, you will continue to use just about any element of it as a debate tool, and keep things focused on that simplistic approach.

    Fact: GHGs will dangerously change the climate if left completely unchecked, which will have a cost in both lives and dollars (blood and treasure, as the neocons are so fond of saying about wars), and the number of lives and degree of suffering will depend on how we (i.e. the human race) behave and react… and 3,000 years of human history show that we handle such stress very, very poorly and unfairly. The fact that the population is projected to increase as much as it is (which is the foundation of much of that GDP-growth factor to which you are so wedded) will simply mean more people with an opportunity to suffer, and more population pressure to cause suffering.

    So no matter how you want to argue it, major (6˚C), unrestrained climate change is likely to cause suffering on an unimagined scale.

    Nit picking one part of one report to argue otherwise, just to make yourself feel good about pursuing your own personal, short term economic goals is… well, you judge for yourself.

  36. 136
    Ray Ladbury says:

    Benjamin says, “Between the 1940’s and 2000’s U.S. agricultural output more than tripled, while the United States Department of Agriculture’s (USDA) index of aggregate inputs (land, labor, capital and other material inputs) remained essentially unchanged.”

    Hmm, I notice you pointedly left out “energy” and petroleum, both of which are used much more intensively in farming in the US.

    So, cetera paribus, I would agree, except your cetera ain’t paribus!

  37. 137
    Ray Ladbury says:

    Benjamin says, “And by the way, relocating hundred of millions of people or building hundred of kilometers of dikes over a century is not a problem AT ALL.”

    After all, the partition of the Indian subcontinent went off without a hitch, right?

    Oh, wait…

    Benjamin, you are a wonderful example of the adage that a man thinks that everything he doesn’t understand must be easy. Judging by your performance to date, I’d wager you think just about everything is easy.

  38. 138
    David B. Benson says:

    Benjamin — I recommend reading Mark Lynas’s “Six Degrres”.. Here is a summary:
    http://www.marklynas.org/2007/4/23/six-steps-to-hell-summary-of-six-degrees-as-published-in-the-guardian

  39. 139
    Benjamin says:

    @Witgren
    Yes i know all the that.
    I’m not the one who thinks that climate is the number 1 factor for everything in life.

    On housing :
    Well, the same way houses were built over this century.
    Do you think people were asking themselves this kind of question in 1900′s ?

    @Bob (Spaerica)
    Ok so you disagree with IPCC scenrios then ?
    Do you find them unrealistic ?

    I don’t understand how you can disagree with the economical growth and agree with the CO2 emission numbers.
    You can’t really have one without the other…
    Clearly if you think that such growth can’t be sustained, then CO2 emissions are to be lower than those indicated in those SRES scenarios.

    This is how SRES scenarios are defined :
    “A scenario is a coherent, internally consistent and plausible description of a possible future state of the world.”
    Coherent… internally consistent…. plausible.
    Clearly you seem to disagree on coherence (GDP growth not linked to fossil fuels emissions) and plausibility.

  40. 140
    Ray Ladbury says:

    Rod, Gilles the troll said that there was no evidence that increased temperature had a negative effect on GDP. I cited this evidence to show he was wrong.

    This is not at all controversial. The correlation exists. There are theories as to why, but no consensus. In addition to the effect on agriculture there is the fact that a warmer climate means things wear out faster–and in many cases a warmer climate is also wetter, which also increases wear-out rates. There are other theories that make note of higher incidence of debilitating diseases like malaria or bilharzia. Having lived in the tropics, I can assert that all of the above are true. This is why I admonish people not to comfuse fetid with fertile.

  41. 141
    Ray Ladbury says:

    Rod,
    I think that it is beyond dispute that climate science is a mature science–so mature, in fact that there are not contending theories of Earth’s climate, just the one model that manages to explain an astounding diversity of phenomena. What would you add to BPL’s definition of maturity that climate science does not meet? Is quantum mechanics mature? Relativity? How about thermodynamics or electromagnetism? Climate science is older.

    You have been a lot longer on assertions than support for them of late, Rod.

  42. 142
    Ray Ladbury says:

    Neil Bates, The sustainable societies I was referring to were mainly those on Pacific Island Archipeligos. They practiced various forms of population control–including abortion and even occasional mass suicide–and many persisted for hundreds of years. That is pretty sustainable. Standard of living was generally not high; nor was life expectancy.

    I do believe sustainability is possible–not easy, but possible. Moreover, I don’t think it involves zero economic growth, since increasing technology can increase the value of goods and services without increasing consumption. I do not claim to know what a sustainable modern society would look like. I do think it is possible, and I don’t think it would mean an end to progress.

  43. 143
    Susan Anderson says:

    Suggest people stop feeding the trolls. Their questions have been dealt with thoroughly, patiently, and politely, and those of us who can learn from the responses have done so. It is obvious the canned and false assertions will go on with decreasing logic no matter how exact and well explained the responses.

    In the meanwhile, I wondered about the absence of information about “winner” species – skates, algae, microbes etc. in the ocean, insects, animals able to adapt and increase in urban and suburban settings (coyotes, foxes, deer, raccoons). In general, loss of rarer species and of balance (bees and colony collapse disorder as far as I’ve been able to see is due to several causes, but warming is a likely contributor to most of them). We spray and kill the natural predators. Carp in the Great Lakes?

    I found this presentation about ocean change/degradation in a recent comment on another article here:
    http://sackler.nasmediaonline.org/2007/ile/jeremy_jackson/jeremy_jackson.html

    And when it comes to flora, climate change is also advantaging some undesirable items such as poison ivy (increased urushiol potency) and I am seeing a lot more predatory vines in the mid-Atlantic states (mile-a-minute vine, etc.), seem to remember something about kudzu as well. Dammit vine, anyone (I’m vague on this but it’s a lovely descriptive moniker)?

  44. 144
    Snapple says:

    The Guardian published two excellent articles on June 3. I have posted them on them on my last two posts.

    A professor named John Abraham wrote one of the articles and also has a great slide show debunking Lord Monckton.

    He shows how Lord Monckton mischaracterizes and fabricates what real scientists say. It’s really terrific.

    http://www.stthomas.edu/engineering/jpabraham/

  45. 145
    Ray Ladbury says:

    Benjamin, don’t be a moron. The economic scenarios are just that–possible ways in which we could reach a sufficiently high CO2 concentration to see 6 degrees (roughly 2 doublings over pre-industrial levels). There are other ways as well: energy use could become less efficient as we try to keep a crumbling infrastructure viable in a warmer and more hostile world. There’s another scenario–equal energy burned to achieve much less growth. What matters is how much CO2 gets into the atmosphere, not how it gets there.

  46. 146
    Doug Bostrom says:

    Benjamin: “And by the way, relocating hundred of millions of people or building hundred of kilometers of dikes over a century is not a problem AT ALL.”

    I think Benjamin’s throwing a hint that he’s joking, doing a parody.

  47. 147
    Jim Eager says:

    Susan Anderson, is right. People like Benjamin who are completely out of touch with physical reality are not worth wasting any further time on.

  48. 148
    Richard Steckis says:

    126
    Edward Greisch says:
    4 June 2010 at 2:36 PM

    “To everybody who is arguing over GDP vs climate: The way climate interacts with GDP is through agriculture. Workers work the hardest when they are well fed. They don’t work at all when they are not fed. What farmers need is a STABLE climate and a climate that is THE WAY IT WAS when farmers began growing that crop in that place.”

    You couldn’t be further from the truth. Have you not heard of plant breeding? Through plant breeding we can modify crop varieties to become more tolerant of climatic changes.

  49. 149
    Frank Giger says:

    Mr. Ladbury, I think there isn’t any concensus on why warmer climed places have a lower GDP is the monkey wrench of poor governance and an over-all lack of rule of law.

    When we take a look at Haiti versus the Dominican Republic we can see how governance can effect GDP as much as latitude on the globe.

    Or look at Zimbabwe before and after de-colonization. Climate change didn’t turn it from one of the bread baskets of Africa into the land of starvation. Mismanagement and poor leadership did.

    There’s just too much political noise in the signal to say “the hotter, the poorer.”

  50. 150
    Doug Bostrom says:

    OT FYI, Accuweather Climate Blog linked from RC “Other Opinions” list has moved… new location is http://www.accuweather.com/blogs/climatechange/Science

    Another time sink, wouldn’t want to miss it…


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