摘要
利用塔里木河流域1986-2005年气温、降水逐日格点数据和MPI-ESM-LR模式驱动的CCLM区域模式模拟数据,评估了CCLM模式对塔里木河流域极端气候事件的模拟能力。同时采用EDCDF法对最高气温、最低气温和降水预估数据进行偏差校正,并计算了2016-2035年极端气候指数。结果表明:该区域气候模式对塔里木河流域年平均最高气温、最低气温和降水的空间分布具有较强的模拟能力,特别是气温空间相关系数在0.97以上;该模式对于极端气候事件也有着较强的模拟能力,大部分极端气候指数的空间相关系数达到了0.01的显著性水平。通过偏差校正,有效地提高了气候要素及相应的极端气候指数的模拟精度。预估未来RCP4.5情景下,塔里木河流域未来(2016-2035年)极端暖事件(暖期持续指数、气温日较差、暖昼、极端最高气温)有增加的趋势,未来流域中部的干旱可能更严重,而流域内环塔里木盆地区域将变湿。
Reduction of uncertainty in simulations and projections of regional climate models is a critical issue for regional climate impact studies, especially in context of climate extremes. Based on daily grid datasets （1986-2005） of precipitation, maximum and minimum temperature that interpolated by observed data and simulated by regional climate model CCLM, 12 climate extreme indices recommended by the CCI/CLIVAR/JCOMM-ETCCDMI are calculated and the climate extreme simulation ability of CCLM is evaluated for Tarim River Basin （TRB） for the period 1986-2005. To improve the availability of simulated data, the systematic bias between observations and model projections are corrected by the equidistant CDF matching method （EDCDFm）. Then the projected change of the climate extreme is studied by the climate extreme indices calculated by the bias-corrected simulated data. The results show that the regional climate model CCLM can reproduce the spatial distributions of annual mean maximum temperature, minimum temperature, precipitation and climate extreme indices. The spatial correlation of temperature can arrive 0.97. The spatial correlations of most climate extreme indices are significant at 0.01 significance level. The application of the bias correction has shown that it effectively improves the bias in climate variables and most of the corresponding climate extreme indices of the TRB. However,the percentile-based tem- perature indices （Tx90p,tn10p,WSDI） are not simulated and improved well. But their bias and root-mean-square- error are improved by using the bias-correction method. Under RCP4.5 scenario, extreme warm events （WSDI,DTR,Tx90p,TXx） will increase. The annual total precipitation （PRCPTOT） will increase mainly in the edge of TRB. Extreme precipitation events （Rx1day,R95pTOT,SDII） have a decreasing trend. According to the spatial distribution of CDD and CWD,middle part of Tarim River basin will get drier and the edge of Tarim River Basin will get wetter during 2016-2035.
出处
《干旱区地理》
CSCD
北大核心
2014年第3期490-498,共9页
Arid Land Geography
基金
新疆维吾尔自治区科技支撑项目(201331104)
国家自然科学基金项目(41101023)
