Slashdot Mirror
Doubling of CO2 Not So Tragic After All?
carvalhao writes "The Register reports on a study from NASA and the US National Oceanic and Atmospheric Administration that claims that new climate models that account for the effects of increased CO2 levels on plant growth result on a 1.64 C increase for a doubling of CO2 concentrations, a far less gloomy scenario than previously considered."
1.64DegC is still within the error bars for climate sensitivity that have not significantly changed since the 1970's; ie: 3.0DegC +/- 1.5 degC for a doubling of CO2.
The abstract itself claims: "By accelerating the water cycle, this feedback slows but does not alleviate the projected warming, reducing the land surface warming by 0.6C. Compared to previous studies, these results imply that long term negative feedback from CO2 induced increases in vegetation density could reduce temperature following a stabilization of CO2 concentration." [My emphasis] - In other words nature will suck up our excess if we stop pumping into the atmosphere faster than she can cope with it, which has been the assumption for many years.
Disclaimer: I'm not rubbishing the study I think it's a valuable in the effort to reduce the above mentioned error bars. However despite the inference of the summary it does not change the risk assesment one iota.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
There's nothing wrong with ideology. Skepticism is an ideology. Without ideology we wouldn't have the scientific method.
You know, we don't actually know *what* causes ice ages (and no it's not the gulfstream) ... the long-term graphs seem to indicate pretty strongly that one is indeed coming :
http://www.landcareresearch.co.nz/research/globalchange/images/temp-001.gif (source http://www.landcareresearch.co.nz/research/globalchange/climate_change.asp)
I mean the graph has jumped 10 degrees downward 10 times like clockwork every 100000-110000 years or so. Seems logical that it will in fact jump again, doesn't it ? Last time it jumped was about 108000 years ago. So it's pretty much bound to jump again. And I repeat, we do *not* know what causes this, and the temperature drops like a stone (weather apparently goes from normal to ice age conditions, meaning permafrost in the northern sahara, and a *very* white Christmas in southern Mexico, while Florida becomes an ice sheet, just to give an idea how extreme this is, in less than 10 years). That's 10 years, triggered by some unknown event, after which America less inhabitable than Greenland. Even the deserts of the middle east will be cold conditions, and harsh winters, at best.
Of course the error margin on these data are like 500-1000 years, which is a lot of time. But while we don't know why or how, *something* is going to trigger an ice age, pretty soon now. But that's "pretty soon" in "very likely in the next 2000 years" ...