Extreme wildfires are turning the world's largest forest ecosystem from carbon sink into net-emitter

The vast boreal forests of the Northern Hemisphere stretch from Scandinavia through Siberia, Alaska and Canada. They cover a tenth of the world's land but hold one-third of the land's carbon, stored mainly in organic-rich soils and in trees. Now, a new study in the journal Science provides further evidence that emissions from wildfires in high northern latitudes are already increasing at an alarming rate.