[interesting post on Mobilize Globally - Will]
----- forwarded message -----
Date: Thu, 09 Nov 2000 20:15:06 +0100
From: "secr(MG!)" <[EMAIL PROTECTED]>
Subject: First climate model to incorporate realistic plant life produces dismal
predictions
----- forwarded message -----
Subject: [gaia-l] First climate model to incorporate realistic plant life
produces dismal predictions
Date: Thu, 9 Nov 2000 11:50:17 -0400 (AST)
From: Mark Graffis <[EMAIL PROTECTED]>
Reply-To: [EMAIL PROTECTED]
Growth factor
A new climate model that incorporates realistic plant life suggests
much faster global warming than previously predicted.
Peter Cox and his colleagues at the Hadley Centre in Berkshire,
England, have created the first model that takes into account
interactions between plant growth and other environmental factors,
such as temperature and carbon dioxide levels.
The results are dismal. By 2050, Cox predicts that the biosphere will
make a quick switch from sucking up a small amount of carbon dioxide
to belching out a lot.
Land temperatures could rise significantly - by 6 °C instead of the 4
°C predicted by models that don't allow for changing patterns of
vegetation.
"The severity of this surprised us," says Cox. "We didn't anticipate
the biosphere would be this important."
Using 'coupled' models is vital, says Ian Woodward, a vegetation
modeller from the University of Sheffield, England: "What we've got
now is the best way forward."
Vegetation die-off
Plants usually absorb more carbon dioxide as more is pumped into the
atmosphere. But as it gets hotter, the amount absorbed by plants
levels out, while the amount expelled by microorganisms in the soil
increases exponentially.
This means that overall the biosphere begins to have a warming effect.
(New Scientist, 23 October 1999, p 20) Drying and warming will turn
large areas of the Amazon into grassland, further accelerating the
effect, Cox predicts. (New Scientist, 6 May, p 7)
However, Woodward cautions that other models don't predict such a
large die-off of vegetation in the Amazon.
More at: Nature, (vol 408, p 184)
Correspondence about this story should be directed to
[24][EMAIL PROTECTED]
1900 GMT, 8 November 2000
Nicola Jones
New Scientist Online News
5. http://www.newscientist.com/
