Tropical rainforests are often called the "lungs of the planet" because
they generally draw in carbon dioxide and breathe out oxygen. But the
amount of carbon dioxide that rainforests absorb, or produce, varies
hugely with year-to-year variations in the climate. In a paper published
online Feb 6 2013 by the journal Nature, a team of climate
scientists from the University of Exeter, the Met Office-Hadley Centre
and the NERC Centre for Ecology & Hydrology, has shown that these
variations reveal how vulnerable the rainforest is to climate change.