Short-term climatic impacts of afforestation in the East Asian monsoon region

The influence of changes in vegetation cover on short-term climate over the East Asian monsoon region is simulated using the Community Climate System Model Version 3.5. The results show the annual mean surface air temperature significantly decreases by 0.93℃ in response to afforestation over the East Asian monsoon region. Also, surface air temperature decreases by 1.46 and 0.40℃ in summer and winter, respectively. The cooling is caused by enhanced evapotranspiration （ET） produced by increased forest cover. Evapotranspiration is greater in summer than in winter, so summer cooling is greater than winter cooling. The annual mean precipitation increases in response to afforestation, with a maximum of 7% in April. Water vapor increases significantly because of greater latent heat flux release. Meanwhile, afforestation leads to higher surface roughness, which decreases surface wind speed and induces an ascending air motion. These factors can produce more clouds and precipitation. Moreover, the surface albedo and the reflective solar radiation are reduced in response to afforestation.