中国区域陆面覆盖变化的气候效应模拟研究

基于MODIS和CLCV陆面覆盖资料，利用区域气候模式RegCM4分别进行两组24年（1978-2001年）的数值模拟试验，研究中国区域陆面覆盖变化对区域气候的影响。结果表明，以荒漠化和植被退化为主要特征的陆面覆盖变化通过改变陆面能量、水分平衡与大尺度环流进而对气候要素产生重要影响。夏季，中国南方地区普遍降温，季风边缘区及藏北高原气温升高，降水减少；季风边缘区与西北地区气温年际波动加剧；内蒙古中东部地区西南风增强，进而水汽输送增强，一定程度上增加了该地区降水。冬季，中国东部地区偏北气流增强，更多干燥冷空气南下，使得黄河以南地区降水减少、气温降低。

A Simulation Study on Climatic Effects of Land Cover Change in China

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.