Paris, 21 May 2020 (AFP) – Tropical forests could lose their role as carbon stocks if daytime temperatures exceed 32ºC, which could occur in almost three quarters of the forests if the global climate warms up to 2ºC, according to a study published in this Thursday (21) in the journal Science.
"Tropical forests currently store the equivalent of a century of carbon dioxide emissions. However, climate change could reduce these reserves if tree growth slows down or if tree mortality rates increase, which at the same time. it would accelerate climate change, "Cirad, a French agronomy research institute, said in a statement.
Scientists measured more than half a million trees in 813 rainforests around the world to assess the amount of carbon stored.
Currently, rainforests act as carbon deposits, "despite rising temperatures," the statement said.
However, "the carbon reserves stored in these forests will remain stable as long as the daytime temperature does not reach 32ºC. Beyond that limit, the reserves decrease very sharply", explained Bruno Hérault, co-author of the study and Cirad's specialists in tropical forests.
The current objective set out in the Paris Agreement is to keep temperatures rising below 2 ° C, but this "would lead to overcoming these 32 ° C in a large number of tropical forests".
"If we limit world average temperatures to an increase of 2ºC over pre-industrial levels, this causes almost three quarters of the rainforests to be above the temperature limit we identified," warned Martin Sullivan, lead author of the publication, a researcher at Leeds University and Manchester Metropolitan University, quoted in the statement.
The danger, then, would be that "forests would, in turn, become carbon emitters".
"With each additional degree of temperature, tropical forests would release 51 billion tons of CO2 into the atmosphere," insisted Martin Sullivan.
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