Rising CO2 won’t make trees grow more, study suggests

It found rising CO2 levels in the atmosphere since pre-industrial times made trees more efficient at using water, but didn’t increase the growth of their trunks — and therefore the amount of carbon they stored, the researchers reported in the Proceedings of the National Academy of Sciences last week. What’s special about the trees in the recent Canadian study is they’re North America’s oldest boreal trees, allowing researchers to track changes much farther back in time, said Étienne Boucher, a geography professor at the University of Quebec in Montreal who co-authored the study. The researchers said the findings about trees’ water use mean we may need to revise our understanding of how the water cycle will be affected by rising CO2 and climate change, as a lot of the Earth’s water moves through trees and plants.

Source: www.cbc.ca