Relative impacts of increased greenhouse gas concentrations and land cover change on the surface climate in arid and semi-arid regions of China
Relative impacts of increased greenhouse gas concentrations and land cover change on the surface climate in arid and semi-arid regions of China
复制标题
温室气体浓度增加和土地覆盖变化对中国干旱半干旱地区地表气候的相对影响
DOI：
10.1007/s10584-017-2025-x
复制
发表时间：
2017
期刊：
影响因子：
4.8
通讯作者：
杨宗良
中科院分区：
文献类型：
--
作者：
徐忠峰;杨宗良
四个动态降尺度模拟进行不同的土地覆盖图和温室气体（GHG）水平的组合，使用嵌套在社区地球系统（CESM）模型的天气研究和预报（WRF）模型。利用伪全球变暖降尺度方法有效地分离了气候模式中的人为信号和内部噪声。在此基础上，研究了人为增加温室气体浓度和土地利用/土地覆被变化（LULCC）对中国干旱半干旱地区平均气候和极端事件的影响。结果表明，温室气体浓度的增加导致干旱和半干旱地区2 m高度（T2 m）的地表气温显著升高1 ~ 1.5 °C，暖日气温（TX 90 p）的升高幅度大于冷日气温（TX 10 p）。此外，由于温室气体引起的水分再循环率和降水效率的增加，在寒冷的季节（11月至次年3月），在干旱地区的降水增加了30-50%。LULCC导致T2 m、TX 90 p和TX 10 p显著降低约0.3 °C。在暖季和冷季，区域LULCC分别占T2 m下降的66%和68%。T2 m的其余变化是由于全球LULCC引起的侧边界条件的变化。在响应LULCC，无论是温暖的和寒冷的日子温度显示了显着的下降，在寒冷的季节，这主要是由区域LULCC的结果。在中国的干旱和半干旱地区，土地利用、土地利用变化和气候变化引起的降水变化一般较弱。
Four dynamical downscaling simulations are performed with different combinations of land cover maps and greenhouse gas (GHG) levels using the Weather Research and Forecasting (WRF) model nested in the Community Earth System (CESM) model. A pseudo-global warming downscaling method is used to effectively separate the anthropogenic signals from the internal noises of climate models. Based on these simulations, we investigate the impacts of anthropogenic increase in GHG concentrations and land use and land cover change (LULCC) on mean climate and extreme events in the arid and semi-arid regions of China. The results suggest that increased GHG concentrations lead to significant increases in the surface air temperature at 2 m height (T2m) by 1–1.5 °C and greater increase in the warm day temperature (TX90p) than the cold day temperature (TX10p) in the arid and semi-arid regions. Moreover, precipitation increases by 30–50% in the arid region in cold season (November to March) due to the GHG-induced increase in moisture recycling rate and precipitation efficiency. LULCC leads to significant decreases in the T2m, TX90p, and TX10p by approximately 0.3 °C. The regional LULCC accounts for 66 and 68% decrease in T2m in warm and cold seasons, respectively. The rest changes in T2m results from the changes in lateral boundary condition induced by the global LULCC. In response to LULCC, both the warm and cold day temperatures show a significant decrease in cold seasons, which primarily results from the regional LULCC. LULCC-induced changes in precipitation are generally weak in the arid and semi-arid regions of China.