PARIS, Aug 27 — Global warming is driving leafy tropical canopies close to temperatures where they can no longer transform sunlight and CO2 into energy, threatening total collapse if the thermometer keeps climbing, according to a study Thursday.
If tropical forest’s average surface temperature warms 4C above current levels — widely considered a worst-case scenario — “we’re predicting possible total leaf death,” he said. Doughty and his team used data from the Nasa Ecostress satellite — designed to measure plant temperatures — validated with ground observations, based in part on sensors attached to individual leaves.There remain uncertainties as to how high leaf temperatures might impact the forest as a whole, the scientists cautioned.
“The Amazon is currently experiencing higher levels of mortality than Central Africa and that could possibly be due to the high temperatures we’ve seen there,” said Doughty. They also harbour half or more of the world’s plant biodiversity, with at least 40,000 different tree species, according to the Intergovernmental Panel on Climate Change .