摘要
利用50 km×50 km水平分辨率区域气候模式Reg CM4.0,嵌套全球气候模式输出结果 BCC_CSM1.1,模拟了新的温室气体排放情景RCP(Representative Concentration Pathw ay)下21世纪东亚地区的气候变化,针对模拟结果中云南及周边地区进行分析。对模拟的当代(1986 2005年)气候进行了检验,结果表明,模式能够模拟出该区域平均气温和降水的季节分布,但气温模拟存在一定冷偏差,冷季降水模拟偏多。在RCP8.5情景下,研究区域未来干季(11月至翌年4月)、湿季(5 10月)气温将逐渐升高,同时降水量将减少,干、湿季气温和降水变化存在一定的空间差异。以连续干旱日数CDD、降水与蒸发之差(P-E)、植物根区土壤贮水量RSW 3个指标进行的干旱性分析表明,全球变暖背景下未来云南及周边地区的干旱化趋势将持续并加重,其中干季更明显。
Driven by the global climate model of BCC_CSM1. 1,climate change over East Asia in the 21 stcentury is simulated by a regional climate model,Reg CM4. 0,under the newemission scenarios of RCP( Representative Concentration Pathway). In the present study,the analysis is focused on Yunnan Province and its surrounding areas located in southwestern China. Simulations of present day climate( 1986 2005) by Reg CM4 are compared against observations to validate the model performance. The results showthat Reg CM4 can reproduce the observed annual cycle of the regional mean temperature and precipitation well,although a cold bias over the region and an overestimation of precipitation in the dry( cold) season can be found in the simulations. Significant warming and a general decrease of precipitation in both the dry( November to next April) and wet( M ay to October) seasons in the 21 stcentury are projected by the model under RCP8. 5 scenario. The changes showdifferences in spatial distribution in the two seasons. The drought events are measured by the indices of the maximum number of consecutive dry days( CDD),differences between precipitation and evaporation( P- E),and root zone soil water content( RSW). Analysis of their future changes indicates that the drought will continue and aggravate under the global warming. This is more profound in the dry season compared with the wet season.
出处
《高原气象》
CSCD
北大核心
2015年第3期706-713,共8页
Plateau Meteorology
基金
公益性行业(气象)科研专项(GYHY201306019)
国家自然科学基金面上项目(41375104)
中国气象局气候变化专项(CCSF201509)
关键词
气候变化
区域气候模式
云南
干旱
Climate change
Regional climate model
Yunnan
Drought
