Vegetation-based climate mitigation in a warmer and greener World

Vegetation changes have been suggested as a climate mitigation option, but the numerous feedbacks between vegetation and climate are not well understood. Here, the authors show that greening leads to surface cooling in many areas, but the size of the effect depends on the background climate.The mitigation potential of vegetation-driven biophysical effects is strongly influenced by the background climate and will therefore be influenced by global warming. Based on an ensemble of remote sensing datasets, here we first estimate the temperature sensitivities to changes in leaf area over the period 2003-2014 as a function of key environmental drivers. These sensitivities are then used to predict temperature changes induced by future leaf area dynamics under four scenarios. Results show that by 2100, under high-emission scenario, greening will likely mitigate land warming by 0.71 +/- 0.40 degrees C, and 83% of such effect (0.59 +/- 0.41 degrees C) is driven by the increase in plant carbon sequestration, while the remaining cooling (0.12 +/- 0.05 degrees C) is due to biophysical land-atmosphere interactions. In addition, our results show a large potential of vegetation to reduce future land warming in the very-stringent scenario (35 +/- 20% of the overall warming signal), whereas this effect is limited to 11 +/- 6% under the high-emission scenario.