Photosynthesis in the jungle may stop, and oxygen will run out

A new study shows that some leaves in tropical forests from South America to Southeast Asia are heating up so much that they could lose their ability to photosynthesize, with serious consequences for the world’s forests.

The ability of leaves for photosynthesis – the process by which they obtain energy from carbon dioxide, sunlight and water – begins to decline when their temperature reaches about 46.7 degrees Celsius. As a result of this process, oxygen is released into the earth’s atmosphere.

While it may not seem like a high temperature, leaves can get much hotter than the surrounding air, according to a report published Wednesday in the journal Nature a group of scientists from the USA, Australia and Brazil.

Scientists used temperature data obtained from thermal satellite sensors of the International Space Station, located at an altitude of 400 kilometers above Earth. They combined them with field observations from leaf heating experiments, in which scientists carefully placed sensors on leaves.

The scientists weren’t looking at average temperatures, they were looking at extremes, explained Christopher Doughty, assistant professor of environmental computer science at Northern Arizona University and co-author of the report. They found that the average temperature at the top of the forest dome reaches 34 degrees Celsius, but some exceed 40 degrees Celsius &

According to the report, 0.01% of leaves currently have a critical temperature where their ability to photosynthesize is impaired, potentially leading to the death of leaves and trees.

This percentage, although negligible, will increase with climate change, the report says, threatening the world’s rainforests, which cover roughly 12% of the planet’s surface and contain more than half of the species on Earth. They also play an important role in carbon sequestration and storage and help regulate the global climate.

“When fragments of the forest begin to disappear, even leaves on individual trees, all possible feedbacks occur,” Doughty said in an interview with reporters.