土地利用变化对我国区域气候影响的数值试验

使用RegCM2区域气候模式单向嵌套澳大利亚CSIRO R21L9全球海-气耦合模式,通过将中国区域植被覆盖由理想状况改变为实际状况的数值试验对比分析,探讨了当代中国土地利用变化对中国区域气候的影响,并对结果进行了统计显著性检验。研究表明,土地利用的变化,会导致我国西北等地区年平均降水减少,导致年平均气温在内陆部分地区升高和在沿海个别地区降低,引起许多地方夏季日平均最高气温升高,而冬季日平均最低气温则在我国东部部分地区降低的同时在西北地区升高,土壤湿度的变化表现为大范围的降低。研究同时表明,相同的土地变化在不同的地理环境下引起的气候要素变化有一定的不一致性。

Simulation of Effects of Land Use Change on Climate in China by a Regional Climate Model

Climate effects of land use change in China as simulated by a regional climate model (RegCM2)are investigated. The model is nested in one-way mode within a global coupled atmosphere-ocean model(CSIRO R21L9 AOGCM). Two multi-year simulations, one with current land use and the other withpotential vegetation cover, are conducted. Statistically significant changes of precipitation, surface airtemperature, and daily maximum and daily minimum temperature are analyzed based on the differencebetween the two simulations. The simulated effects of land use change over China include a decrease ofmean annual precipitation over Northwest China, a region with a prevalence of arid and semi-arid areas;an increase of mean annual surface air temperature over some areas; and a decrease of temperature alongcoastal areas. Summer mean daily maximum temperature increases in many locations, while winter meandaily minimum temperature decreases in East China and increases in Northwest China. The upper soilmoisture decreases significantly across China. The results indicate that the same land use change 05-cause different climate effects in different regions depending on the surrounding environment and climatecharacteristics.