Projection Of Climate Hazard And Risk In China Considering Climate Change By CMIP5 Models

Under the background of global warming,extreme events become more frequent and heavy,and have great influences on human society.Thus,it is most important that to learn the relationship between meteorological factor and disaster risks,to project the spatial and temporal pattern of climate disaster risks by extreme events changing,and further to learn the socio-economic impacts.In this study,with calculating the indexes and its return periods of extreme precipitation and temperature by similated results of 17 models from Coupled Model Intercomparison Project Phase 5?CMIP5?,combining with simulated socio-economic data under Shared Socio-economic Pathway and land-use data to project the climatic disaster risks and its socio-economic impacts in China during21^st Century.The results show that:?1?The number of precipitation extremes will increase in China,particularly in the south of the Yangtze River and North China.The number of high temperature extremes will increase,particularly in Northwest and south of Southwest.It shows that the extreme precipitation and extreme high temperature will intensify and expand.There is a tendency toward acidification in north and south China.The number of drought extremes will increase in Northwest China,Inner Mongolia,Southwest and Southern China in the future.?2?In the 21^st century,from the analysis of different return periods of climatic risk,it shows that the region with large loss of population and GDP will locate in developed areas,such as North China,East China and South China.It will have a much higher effect under the RCP4.5 scenario.The exposed GDP caused by flood and high temperature hazard will increase under the two scenarios,while by drought hazard will increase in the middle of 21^st century under the two scenarios,but continue increase under the RCP8.5 scenarios and decrease under the RCP4.5scenarios in the later 21^st century.The exposed population caused by flood and high temperature hazard will increase in the middle of the 21^st century under the two scenarios,but continue increase under the RCP8.5 scenarios and decrease under the RCP4.5 scenarios in the later 21^st century.The exposed population caused by drought hazard will decrease in the 21^st century.?3?There will be a high risk of flood disasters in North and East China,especially in developed region.The area with high level disaster risk will expand with time in 21st century under the RCP4.5 and RCP8.5 scenarios.There will great possibility,wide range of flood risk in China by the end of 21st century.?4?The future high level of risk of flood disasters is forecasted to mainly affect North China and coastal area of East China.Compared to 1986–2005,under the RCP4.5 and RCP8.5 scenarios,the area with level V disaster risk will expand first and then shrink.And it will expand with the increase of return period.The area will be greater under RCP4.5 scenarios by the middle of 21^st century.?5?There will be a high risk of disasters related to high temperatures in North China and coastal area.Under the RCP4.5 scenario,the area with level V disaster risk will expand first and then shrink,and expand with the increase of return period.Under the RCP8.5 scenario,the area with level V disaster risk will expand with time.And it will expand with the increase of return period.?6?The future high level of risk of synthetically climatic disasters is forecasted to mainly affect the area of the south and east of the Huhuanyong line.And the low level risk of disasters is in northwestern Tibet and Xinjiang.Under the RCP4.5scenario,the area with level V disaster risk will expand first and then shrink.Under the RCP8.5 scenario,the area with level V disaster risk will expand with time.It is indicated that the impact area range of the high risk of synthetically climatic disaster in the mid-21st century under the RCP4.5 scenario will be wider,and the high level risk area in the late 21st century under the RCP8.5 scenario will have a wider influence,and decreases with the increase of the disaster grade.