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Precipitation changes in spring (MAM) and summer (JJA) over theYangtze River Basin during 1880 to 2011 were analyzed based onobservation datasets from 21 gauge stations.The projected changes inprecipitation were evaluated using nine Coupled Model IntercomparisonProject Phase 5 (CMIP5) datasets.The results suggest that interannualand interdecadal changes in spring and summer precipitation occurredduring 1880 to 2011.The Dry-Dry events of seasonal evolution generallyoccurred over the past 132 years.Empirical mode decomposition (EMD) was applied to detect the oscillation periods,in which quasi-3a,5a,15a,and 40a periods of spring and quasi-3a,5a,11a,22a,and 40a periods ofsummer were identified.The abnormal location of western Pacificsubtropical high (WPSH) and insufficient water vapor was found to beassociated with the 2011 spring drought and their sudden change is alsoresponsible for the flood in June.Taylor diagram showed an improvedcapability to simulate monthly precipitation using the nine CMIP5 datasets.The projected precipitation changes show that the significantpositive linear trends of spring precipitation will occur atrepresentative concentration pathways (RCP)2.6 and RCP8.5,whereas summerprecipitation will mainly undergo interannual change.For the projectedspatial pattern of precipitation anomaly,spring precipitation willincrease in the northern basin but decrease in the south under RCP2.6 andRCP8.5 in the 2020s and 2040s.Under RCP4.5,positive anomalies can befound in the middle and lower basins.In contrast to those in the springpattern,the negative anomalies of summer precipitation are concentratedin the middle and lower basins under each RCP.