大尺度土地利用变化对东亚地表能量、水分循环及气候影响的敏感性试验

Sensitivity experiments on impacts of large-scale land use change on surface energy balance,hydrological cycle and regional climate over East Asia

利用NCAR大气环流模式CAM4.0,针对潜在植被和当代植被的分布情形进行了两组25a的积分试验,探讨了土地利用变化对东亚地区地表能量平衡、水分循环和气候的可能影响。结果表明:以森林退化、农田迅速增加为主的当代土地利用变化,显著改变地表属性,使得东亚地区不同季节的地表反照率均明显增加,并显著改变东亚地区的冬、春季节的地表能量和水分循环。此外,当代大尺度土地利用变化对东亚地区大气环流也有一定影响,可引起东亚冬季风环流显著加强和东亚夏季较弱的偏南风异常。当代土地利用变化未能引起东亚地区近地面气温的显著变化,但可引起东亚北(南)部地区春季降水的显著增加(减小)。

Using the NCAR Community Atmosphere Model（ CAM4.0）, two sensitivity experiments in- tegrated 25 years are performed under the conditions of potential vegetation and current vegetation, re- spectively. The possible influences of the land-use change （LUC） on the land surface energy balance, hydrological cycle and climate over East Asia are investigated. Results show that the current LUC fea- tured by rapid forest degradation and cropland increasing significantly alters the land surface characteris- tics, leading to increase of surface albedo in all seasons over East Asia, which in turn changes the sur- face energy balance and hydrological cycle over the region in winter and spring. In addition, impacts of large-scale LUC on the general circulation over East Asia are also detected. Current LUC tends to cause evidently stronger winter monsoon circulation and slightly enhanced summer monsoon. No evident changes of air temperature induced by current LUC are found,but more（less） spring precipitation hap- pens in the north（south） of East Asia under the impacts of LUC.