INSECTS whose populations are booming because of global warming appear to be devouring huge swathes of forest in western Canada and Alaska. Forests in Europe and Siberia may also be under threat. This could lead to a vicious cycle where reduced forest cover leads to more carbon dioxide in the atmosphere, producing further climate change.
Chris Potter, an ecologist at the NASA Ames Research Center in Moffett Field, California, and colleagues analysed satellite images collected by NASA’s Global Ecological Disturbances project to determine how the cover of tree canopies and other vegetation has changed over time.
Nineteen years of satellite…
