关键词: 陆面覆盖变化, 区域气候变化, RegCM4, CLM3.5

Abstract: Regional climate model RegCM4 was used to investigate the regional climate effects of land cover change over China. Two 24-year (1978-2001) simulations, one with the land cover derived from the MODIS data and the other with the CLCV (Chinese land cover derived from vegetation map) data, were conducted for a domain encompassing China. The differences between the MODIS and CLCV data can basically reflect the characteristics of desertification and degradation of vegetation in China. Results indicate that the land cover change has important impacts on local climate through changes of surface energy and water budget and large-scale circulation. In summer, the land cover change leads to decrease in surface air temperature over southern China, reduction in precipitation and increase in surface air temperature in the monsoon marginal zone and the northern Tibetan Plateau, and increase in interannual variability of surface air temperature in the monsoon marginal zone and northwestern China. Strengthened southwesterly winds increase precipitation to some extent in central and eastern Inner Mongolia by enhancing water vapor transport. In winter, enhanced northerly winds bringing more dry and cold air lead to a precipitation reduction and a temperature decline over areas south of the Yellow River.

Key words: land cover change, regional climate change, RegCM4, CLM3.5