Simulations of Water Resource Changes in Eastern and Central China in the Past 130 Years by a Regional Climate Model

Anthropogenic influences on regional climate and water resources over East Asia are simulated by using a regional model nested to a global model. The changes of land use/land cover （LULC） and CO2 concentration are considered. The results show that variations of LULC and CO2 concentration during the past 130 years caused a warming trend in many regions of East Asia. The most remarkable temperature increase occurred in Inner Mongolia, Northeast and North China, whereas temperature decreased in Gansu Province and north of Sichuan Province. LULC and CO2 changes over the past 130 years resulted in a decreasing trend of precipitation in the Huaihe River valley, Shandong Byland, and Yunnan-Guizhou Plateau, but precipitation increased along the middle reaches of the Yangtze River, the middle reaches of the Yellow River, and parts of South China. This pattern of precipitation change with changes in surface evapotranspiration may have caused a more severe drought in the lower reaches of the Yellow River and the Huaihe River valley. The drought trend, however, weakened in the mid and upper reaches of the Yellow River valley, and the Yangtze River valley floods were increasing. In addition, changes in LULC and CO2 concentration during the past 130 years led to adjustments in the East Asian monsoon circulation, which further affected water vapor transport and budget, making North China warm and dry, the Sichuan basin cold and wet, and East China warm and wet.

植被和大气CO_2浓度变化对中国东部水资源环境影响的模拟研究

利用区域气候模式与全球气候模式嵌套,模拟了近百年来植被及CO2浓度变化对东亚区域气候及水资源环境的影响。结果表明,东亚许多地区产生了升温现象,但这种温度变化在地域上具有不均匀性,内蒙古、东北及华北增暖最为显著,而四川北部一些地区却存在降温现象;近百年来植被及CO2浓度变化使东亚一些地区呈现出干旱化的趋势,尤其以淮河流域、山东半岛及云南地区最为明显,但长江、黄河中游地区、江南及台湾地区存在降水增加的趋势,从而使缺水的华北地区的干旱化进一步加剧,而黄河中上游地区的干旱化有所缓解,同时长江流域洪涝灾害的发生频率有增加趋势。