85% of the Amazon rainforest may be lost due to global warming

mongabay.com
March 14, 2009





Warming climate could decimate up to 85 percent of the Amazon rainforest by 2150, according to a new computer model.

The study, to be published in Nature Geoscience by researchers from the UK Met Office's Hadley Centre, found that even a 1-degree rise in global temperatures would cause the "irreversible" loss of large tracts of forest. A larger increase could be "devastating" — 75 percent for a 3-°C-rise and 85 percent for a 4-°C-rise.

"A temperature rise of anything over 1°C commits you to some future loss of Amazon forest. Even the commonly quoted 2°C target already commits us to 20-40 percent loss," said lead author Chris Jones, speaking at a climate conference in Copenhagen. "On any kind of pragmatic timescale, I think we should see loss of the Amazon forest as irreversible."



Aboveground live biomass (AGLB) class map of terra firme old growth forests derived from the decision rule classifier and multiple layers of remote sensing data. © Saatchi el al 2007
"The impacts of climate change on the Amazon are much worse than we thought. As temperatures rise quickly over the coming century the damage to the forest won't be obvious straight away, but we could be storing up trouble for the future," added Vicky Pope of the Hadley Centre, according to The Guardian.

Large-scale Amazon die-off would further worsen warming through massive greenhouse gas emissions, effectively transforming Earth's largest rainforest from a sink to a source of carbon emissions. Trees and vegetation in the Amazon are estimated to store 90-140 billion tons of carbon and have been absorbing CO2 at a rate of 2 billion tons per year in recent decades.





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85% of the Amazon rainforest may be lost due to global warming.

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