1961～2049年汉江流域降水量变化研究

Variation of Precipitation in Hanjiang River Basin in the Period of 1961-2049

主要从两个方面对汉江流域的降水进行了研究。一方面,以文献综述法对1961~2011年的汉江流域降水研究文献进行了综述,比较了相关研究结果;另一方面,利用国际比较计划CMIP5中5个全球模式降尺度资料,预估了该地区到2049年的降水趋势变化。综述结果表明,1961~2011年历史时段内,汉江流域整体的降水变化较小,无明显的变化趋势,有近于17和30年的周期变化的结论。模式数据的预估结果表明,1961~2049年内,汉江流域整体上年降水没有明显的上升或下降趋势,在RCP4.5情景下存在着近17和30年的周期变化;但在RCP2.6和RCP8.5情景下,降水周期发生了变化。在RCP2.6情景下,较明显的周期为5和11年;在RCP8.5情景下,较明显的周期为8和17年。总体结论上,文献综述和模式数据的研究结果基本一致,即汉江流域过去50年以及未来30年,降水整体上没有显著的趋势变化。

From two aspects the research in this paper focuses on the changes of precipitation in the Hanjiang River Basin.On the one hand a literature review about the historical changes in the period of 1961-2011 compares the previous research results;on the other hand using five global climate models(GCMs)from CMIP5,the trend of precipitation in 1961-2049 is projected.The literature review shows the result that there is not clear trend in the precipitation change in the Hanjiang River Basin in the historical period of 1961-2011.While some literatures showed a 17-year-period and a 30-year-period in the time series in their work.Furthermore,the GCMs in this area verify the conclusions from the literature review.There are not obvious upward or downward trend of precipitation in the period of 1961-2049 in the basin,but relatively clear a 17-year-period and a 30-year-period under the scenario of RCP4.5.Under the RCP2.6 and RCP8.5 scenarios the precipitation periods have changed in the times series.Under RCP2.6 the period can be found as 5 a and 11 a,while under RCP8.5 as 8 a and 17 a.In conclusion,the results from the GCMs analysis are basically in accordance with those in literature review.There are no significant trend in precipitation in the Hanjiang River Basin in the past 50 years and also in the next 30 years.