Forests currently take in around 25 to 30 percent of human-generated carbon dioxide emissions, and the Amazon rain forest in particular stores huge amounts of carbon. But many scientists think that if warming climate causes conditions to become drier—a potential impact in many areas—some forests will slow down or even stop photosynthesis, leaving more CO2 in the air, and possibly killing trees.
Current models used for predicting the effects of warming climate show that the Amazon is very sensitive to water stress—an effect that could have vast implications for the forest’s storage of CO2, and possibly its very survival. But in a study published today in the journal Science Advances, researchers at Columbia Engineering report that models have been largely overestimating potential water stress in tropical forests.
The team found that, while models show that increases in air dryness greatly diminish photosynthesis rates in certain regions of the Amazon, observational data show the opposite: In certain very wet regions, the forests instead may even increase photosynthesis rates in response to drier air.
Continue reading at Columbia University Earth Institute
Image via Columbia University Earth Institute