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Post by julianb on Nov 9, 2009 9:40:24 GMT
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Post by hunter on Nov 9, 2009 13:33:03 GMT
Interesting.
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Post by woodstove on Nov 9, 2009 14:29:00 GMT
This computer-model based paper was co-authored by Gavin Schmidt and is of the "it's-worse-than-we-thought" school. The idea that it is a white flag from AGWers is erroneous. Bait and switch is more like it.
Abstract below:
Improved Attribution of Climate Forcing to Emissions
Drew T. Shindell,* Greg Faluvegi, Dorothy M. Koch, Gavin A. Schmidt, Nadine Unger, Susanne E. Bauer
Evaluating multicomponent climate change mitigation strategies requires knowledge of the diverse direct and indirect effects of emissions. Methane, ozone, and aerosols are linked through atmospheric chemistry so that emissions of a single pollutant can affect several species. We calculated atmospheric composition changes, historical radiative forcing, and forcing per unit of emission due to aerosol and tropospheric ozone precursor emissions in a coupled composition-climate model. We found that gas-aerosol interactions substantially alter the relative importance of the various emissions. In particular, methane emissions have a larger impact than that used in current carbon-trading schemes or in the Kyoto Protocol. Thus, assessments of multigas mitigation policies, as well as any separate efforts to mitigate warming from short-lived pollutants, should include gas-aerosol interactions.
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Post by socold on Nov 9, 2009 19:04:19 GMT
Haha "Global Warming Predictions Invalidated"
what hyperbole. When science adds more detail to the picture, these kind of blogs come out of the woodwork and claim the picture has been changed!
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Post by julianb on Nov 10, 2009 9:48:21 GMT
See what you mean Woodstove, but even big Al is saying that CO2 may only account for 40% of global Warming (what warming? see to-day's WUWT charts ) and anything that undermines the models of the IPCC must help to counter their propaganda. Look out for cow farts being the next bogeyman eh?
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Post by hunter on Nov 10, 2009 13:24:14 GMT
See what you mean Woodstove, but even big Al is saying that CO2 may only account for 40% of global Warming (what warming? see to-day's WUWT charts ) and anything that undermines the models of the IPCC must help to counter their propaganda. Look out for cow farts being the next bogeyman eh? AGW is invalidated because CO2 is not the main driver, as was trumpeted here and elsewhere. Notice how the true believers here turn on a dime and still grasp their apocalypse.
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Post by Ratty on Nov 10, 2009 23:21:59 GMT
For some time now, David H. Douglass has been publishing work that would seem to invalidate climate models. www.pas.rochester.edu/~douglass/papers/Erice_final%20draft.pdf"The data show that for the last 25 years RA is not increasing even though RE evidently is. There appears to be a set of mechanisms regulating the CO2 flux to/from the atmosphere to keep RA constant. If so, then there is no simple causal relation between CO2 emissions and the CO2 content of the atmosphere. Under this scenario one can increase or decrease CO2 emissions without changing RA. What then is the rationale for regulating CO2 emissions?" www.pas.rochester.edu/~douglass/papers/E&E%20douglass_christy-color.pdf"These conclusions are contrary to the IPCC [2007] statement: [M]ost of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.”
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Post by trbixler on Nov 11, 2009 5:13:31 GMT
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Post by julianb on Nov 11, 2009 11:29:28 GMT
Reading just the abstract it seems the point was to establish the ratio, which was found to be constant. The means by which this happens isn't specified, nor the reason for the increase above the human contribution.
The natural increase could well be the slight ocean warming over the last century, plus release of the CO2 from deep, now cold water surfacing from the warming of ~800yrs ago. The facts of global greening and increased biological uptake of CO2 have been well documented over the last few years and can be seen on CO2science.org. Plantation growth over logged old growth forest increases CO2 uptake, plus increases in agricultural land use. Ocean algal growth with increased CO2 is documented, and has been estimated to account for 40% of the total annual uptake, all very difficult to quantify, subject of new papers?
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Post by glc on Nov 11, 2009 22:16:14 GMT
The constant CO2 ratio factor, now how easy is that to explain..... seems hard to me, but then many here have suggested totally understood except never mentioned, well the science is settled after all.
wattsupwiththat.com/2009/11/10/bo....-study-says-no/ The paper in the WUWT post is no big deal. It pretty much sums up what's been known for some time, i.e. however much CO2 is emitted by humans it appears that a fixed proportion (~45%) remains in the atmosphere while the rest is absorbed. As human emissions rise it seems reasonable to think that the ratio would change, so although slightly unexpected the findings are not new. In fact some time ago, on another SC24 thread, I tried to show possible CO2 decay times (i.e how long before CO2 concentrations fell back to 1900 levels). I used a 50:50 ratio of emissions to estimate the decay/growth rate.
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Post by trbixler on Nov 12, 2009 0:40:12 GMT
The question is WHY! The paper suggests some possible reasons but the overall observation is not supported with the why of science.
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Post by julianb on Nov 12, 2009 10:24:07 GMT
glc, I do hope it's a long long time before CO2 levels fall to those of 1900, agriculture is only supporting the present world population because of increased levels, and according to a paper in today's CO2science.org if it did revert to 1900 levels, the Amazon rainforest would revert to savannah whereas with present levels it will remain.
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Post by slh1234 on Nov 12, 2009 19:12:58 GMT
glc, I do hope it's a long long time before CO2 levels fall to those of 1900, agriculture is only supporting the present world population because of increased levels, and according to a paper in today's CO2science.org if it did revert to 1900 levels, the Amazon rainforest would revert to savannah whereas with present levels it will remain. I looked for that on CO2science.org. From what I read, that is mostly just modeling again. IMO, the conclusion stated there boils down to substituting one alarmism for another. But supposing they are right, is that really anything to be alarmed about? and is it anything that anyone could control anyway. It is my understanding that the Sahara Desert has come into existence only within the last 5000 years (within the time that people have been on earth). So if the amazon does become a savannah, what other changes take place elsewhere? We really don't know. It's interesting that the point about elevated CO2 levels may be necessary to support the current world population was brought up. I've wondered about that, but I would like to see something more than just what I can read o co2science.org supporting that.
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Post by nautonnier on Nov 12, 2009 19:54:06 GMT
The constant CO2 ratio factor, now how easy is that to explain..... seems hard to me, but then many here have suggested totally understood except never mentioned, well the science is settled after all.
wattsupwiththat.com/2009/11/10/bo....-study-says-no/ The paper in the WUWT post is no big deal. It pretty much sums up what's been known for some time, i.e. however much CO2 is emitted by humans it appears that a fixed proportion (~45%) remains in the atmosphere while the rest is absorbed. As human emissions rise it seems reasonable to think that the ratio would change, so although slightly unexpected the findings are not new. In fact some time ago, on another SC24 thread, I tried to show possible CO2 decay times (i.e how long before CO2 concentrations fell back to 1900 levels). I used a 50:50 ratio of emissions to estimate the decay/growth rate. Indeed you did use a 50/50 ratio - the old Zeno's paradox. Of course that means that after 5 years the CO 2 concentration would be down from today's levels of ~360 to just about 12. So the other calculations that say lifetime of CO 2 is around 5 years would seem to be about right using your figures. Even if you assume that there are more emissions then your simplistic half and half again approach shows that there comes a time when half the CO 2 in the atmosphere is more than can possibly be emitted and balance is achieved. Of course you will also have to show that the levels of CO 2 are of any import to climate - which the last 10 years seem to have falsified.
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Post by socold on Nov 12, 2009 20:26:06 GMT
The constant CO2 ratio factor, now how easy is that to explain..... seems hard to me, but then many here have suggested totally understood except never mentioned, well the science is settled after all.
wattsupwiththat.com/2009/11/10/bo....-study-says-no/ The paper in the WUWT post is no big deal. It pretty much sums up what's been known for some time, i.e. however much CO2 is emitted by humans it appears that a fixed proportion (~45%) remains in the atmosphere while the rest is absorbed. As human emissions rise it seems reasonable to think that the ratio would change, so although slightly unexpected the findings are not new. In fact some time ago, on another SC24 thread, I tried to show possible CO2 decay times (i.e how long before CO2 concentrations fell back to 1900 levels). I used a 50:50 ratio of emissions to estimate the decay/growth rate. Indeed you did use a 50/50 ratio - the old Zeno's paradox. Of course that means that after 5 years the CO 2 concentration would be down from today's levels of ~360 to just about 12. The base is not 0ppm, it's whatever corresponding concentration is in the upper ocean. Even if human emissions stop, 25% of the increase (from preindustrial) remains after 50 years.
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