How plants helped Earth to stay cool

Plant growth spurred by rising levels of carbon dioxide pollution in the atmosphere has slowed the rate of global warming considerably.

Stephen Pacala of Princeton University in New Jersey and his colleagues used an Earth-system model to analyse historical emissions from industry and changes in land use, including deforestation and agricultural development. The team simulated the carbon cycle and climate from 1861 to 2005 with and without the fertilization effect of CO₂ on vegetation.

Although the model did not incorporate certain factors, such as pre-1960 land use, the results suggest that if vegetation had not soaked up so much of the gas, levels of CO₂ would have risen by an extra 85 parts per million — boosting temperatures by about 0.31 °C.

Proc. Natl Acad. Sci. USA http://doi.org/n2c (2013)