Evaluation And Projection Of Temperature And Precipitation Over Yangtze River Basin On Modeling Data From CMIP3/5and CCLM Models

Thinking about that the Yangtze River basin is an important economic region and grain-producing area in China, doing climate change research on it will contribute a better understanding of impact of global warming on the Yangtze River basin, and reveals variation of extreme events in the future in the Yangtze basin, to provide value basis and reference for Chinese Government and services for adaptation to climate change.This article is based on multiple models and meteorological data, using statistical methods, establishing evaluation indicators, assessment of multiple models capacity of the Yangtze River basin climate and projection of climate change, comparing characteristics of different types of differences, the main conclusions are as follows:Compared the simulation results with observations, multi-year trends of models consist with the observations. Capability of CMIP5on years of average temperature and the lower basin simulation of spatial distribution of annual temperature trend rate is stronger. Simulations of rainfall were greater than the observed value and simulations of the middle-lower reaches were closer. Simulations of CMIP5were better in the upper reaches and spatial distribution of precipitation rate. CCLM model was able to simulate the indices of extremes in temperature and precipitation, accurately reflect spatial distribution patterns and characteristics of extreme indices.Average annual temperatures in the RCPs and SRES scenarios are significantly higher from2011to2050.Projected precipitation shows obvious increasing trends under SRES-A1B and SRES-B1scenarios and decreasing trends under SRES-A2scenarios. The precipitation will increase less than6%and decrease less than4% during2011-2050.Projected precipitation shows obvious increasing trends under three different scenarios, magnitude of middle-lower reaches is higher than upper reaches’. The precipitation will increase from4%to12%and decrease less than4%during2011-2050.Projection of extreme temperature indicators show that cold indicators reduce, and warm indicator increase in SRES-A1B and RCP4.5scenario from2011to2040, extreme warm events are more likely to occur in2030s. The warming center will move into the main stream of the middle and lower reaches area of the Sichuan basin. Projection of extreme precipitation indicators will increase in SRES-A1B and RCP4.5except heavy rain day. Center of extreme precipitation will remain in Han Jiang River basin and Dong Ting Lake.