太湖流域气候变化检测与未来气候变化情景预估

基于1954—2006年太湖流域6个气象站点的降水、气温资料,探讨了1954年以来太湖流域的气候变化问题,并同时应用统计降尺度模型SDSM和动力降尺度模型PRECIS,对太湖流域的日降水量和日最高、最低气温进行降尺度处理,建立未来2021—2050年的气候变化情景。结果表明:20世纪90年代以来,太湖流域发生了突变式增温,冬、春季节尤为显著;太湖流域降水变化相对较复杂,Mann Kendall法检测到太湖流域年降水量呈振荡性周期变化,并在1980年和2003年发生突变,而Pettitt方法没有检测出太湖流域年降水量的突变。两种降尺度方法模拟的未来时期日最高、最低气温季节和年的变化情景增幅总体上基本一致,均呈显著增加趋势,与Mann Kendall趋势分析结果一致,高排放情景A2下模拟生成的情景增温幅度较低排放情景B2大,最高气温增加幅度比最低气温明显。降水变化情景差异较大,SDSM模拟的未来时期降水并无明显变化趋势,而PRECIS模拟结果与趋势检验结果较为一致,即未来降水增加趋势明显,增幅较大,总体上全流域年降水量呈增加趋势,并且在未来一段时间内仍将持续增加。

Detection of climate change and projection of future climate change scenarios in Taihu Lake Basin

Based on the data of precipitation and temperature at 6 meteorological stations in Taihu Lake Basin from 1954 to 2006,the problems of climate change in the basin during the past 53 years are investigated.The scenarios of climate change during the period from 2021 to 2050 are generated through the downscaling treatment of daily precipitation and the maximum and minimum daily air temperatures in the basin by means of the statistical downscaling model(SDSM) and the providing regional climates for impacts studies(PRECIS).The results show that since the 1990s,the abrupt increase of temperatures has been occurred in Taihu Lake basin,especially in winter and spring.The change of precipitation in the basin has been relatively complex.The annual precipitation has experienced a fluctuating period change.Abrupt changes of the annual precipitation were detected in 1980 and 2003 by using the Mann-Kendall method.However,no abrupt changes of the annual precipitation in Taihu Lake basin were detected by using the Pettitt method.Generally,the increments of the maximum and minimum daily air temperatures at both seasonal and yearly scales in the future simulated by means of SDSM and PRECIS are basically the same and both exhibit a tendency of significant increase,and they agree with the results of the trend analysis of the Mann-Kendall method.The increment of the air temperature under A2 scenario with high emission is greater than that under B2 scenario with low emission,and the increment of the maximum air temperature is more obvious than that of the minimum air temperature.The changes of daily precipitations generated by the two models are different,that is,no significant change of the future daily precipitation occurs by means of SDSM,while the results simulated by means of PRECIS are in accordance with those of the trend analysis,that is,the increment is large,in general,the annual precipitation in the whole Taihu Lake Basin has a tendency of increase,furthermore,it will continue to increase at certain period in the future.