Climate Response to Vegetation Removal on Different Continents

Abstract

AbstractUnderstanding the climatic effect of vegetation in different regions is important for understanding the climate impact of vegetation change in both the past and future. Here we quantify the climate response to vegetation removal on each continent, except Antarctica, using CESM1.2.2 under pre‐industrial climate condition, and the associated mechanisms are analyzed. Results show that removing the global vegetation lowers the global mean surface temperature (GMST) by 3.65°C. Removing vegetation over Eurasia and North America lowers GMST by 1.83°C and 0.88°C, respectively. They also reduce the global precipitation, but at a much slower rate than that would be caused in the CO2 perturbation experiments. Removing vegetation on all other continents has negligible influence on global climate, but has significant local warming effect due to weakening of evapotranspiration. The removal of low‐latitude vegetation tends to reduce the local precipitation, but increase the precipitation over nearby oceans, especially to the west. The feedbacks of thermodynamic sea ice and oceans amplify the initial direct cooling due to vegetation removal by a factor of >5. The response of ocean circulation has a negligible impact on GMST, but has a significant influence on the pattern of temperature changes by redistributing heat. Without the ocean‐circulation feedback, the Northern Hemisphere would be 1.30°C colder while the Southern Hemisphere 1.17°C warmer when the global vegetation is removed.