The world’s forests are at risk of becoming a source of planet-warming emissions instead of soaking them up like a sponge unless greenhouse gases are controlled, scientists said.
Deforestation emits 20 percent of the world’s carbon dioxide when people cut and burn trees, but standing forests soak up 25 percent of the emissions.
If the Earth heats up 2.5 degrees Celsius (4.5 degrees F) or more, evaporation from the additional heat would lead to severe droughts and heat waves that could kill wide swaths of trees in the tropics of Africa, southern Asia and South America. And emissions from the rotting trees would make forests a source of global warming.
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