Enhanced plant growth over the past decade seems to have slowed the build-up of carbon dioxide in the atmosphere.
Despite the rise in CO2 emissions resulting from human activity, atmospheric CO2 levels have grown relatively little since 2002. To find out why, Trevor Keenan at Lawrence Berkeley National Laboratory in California and his colleagues used ground observations, satellite data and vegetation models to quantify changes in CO2 uptake and release by terrestrial plants worldwide. They found that increased photosynthesis and plant 'greening' have boosted the amount of carbon stored on land. Reduced plant respiration due to the recent slowdown in the rate of global warming also seems to have increased this carbon sink.
However, terrestrial carbon stocks will not offset the accumulation of heat-trapping gases in the atmosphere if emissions continue to grow, the scientists caution.