摘要
洞庭湖流域是我国高温热浪事件多发地区之一,严重威胁人体健康及农业生产,研究高温热浪特征和风险,对当地防暑减灾具有重要指导意义。基于气象站点气温数据（1960~2013年）,综合利用MK检验、概率模型和Copula概率模型,以年最长热浪长度（HWL）、热浪平均高温（HWT）、高温天数（HDL）和高温天内平均高温（HDT）为指数,系统分析了洞庭湖流域高温、热浪的时空规律及风险变化特征。结果表明,流域平均4项高温指数表现出先下降后上升的趋势。总体上,流域东部和东南部高温、热浪强度较大,西部和西南部强度较小,另外,流域高温、热浪的风险和强度变化有一定的空间差异,但总体上升。此外,基于Copula的分析结果表明,洞庭湖流域东大部地区发生高强度热浪和长期高温的风险上升,而西南部以及南部部分地区有所下降。
Global warming has resulted in devastating hazards for human society,such as floods,droughts and heat waves.The Dongting Lake Basin is a region characterized by frequent heat waves and high temperatures in summer.Severe heat waves had brought enormous influences on human health and agriculture in this area.Take the 2013 heat wave as an example,it caused water shortage of more than 3million people and 1.2million animals,and resulted in loss of about$0.18 billion.In recent years,many researchers have focused on the warming characteristics.However,most of this studies focused on the trends of several single indices,while few studies have studied the probability,especially the joint probability of heat waves. On the other hand,duration and temperature are the two inherent characteristics of a heat events,hence,analysis of the joint probability of the two indices could improve our knowledge of severe heat events and for helpful hazards prevention in this region.Therefore,based on the ground surface observed daily temperature dataset（1960-2013）,this study investigated the spatial-temporal characteristics and the risks of extreme heat events（EHE）in the Dongting Lake Catchment,by using MK test,probability distribution and copulas.Four indices,i.e.length of heatwaves（HWL）,mean max temperature in heatwaves（HWT）,hot days（HDL）and mean max temperature in hot days（HDT）were employed to reflect the extreme heat events.The results showed that,the four indices decreased first and then increased obviously after 1987.The amplitudes of EHE were relatively high in eastern and southeastern parts of the catchment,and were relatively lower in western and southwestern parts.Furthermore,though there existed heterogeneous patterns,the amplitude and risk of EHE after 1987 in this area overall increased compared to that in 1960-1987.In particular,the regional mean of 5-year return levels for HWL,HWT,HDL and HDT（HWL5,HWT5,HDL5 and HDT5）increased by 0.5day,0.2℃,2.0day,and 0.2℃,respectively.Moreover,the copula results indicated that the risks of serious heatwaves had increased in the major part of the basin,and decreased in southwestern and southern parts.
出处
《长江流域资源与环境》
CAS
CSSCI
CSCD
北大核心
2015年第10期1729-1735,共7页
Resources and Environment in the Yangtze Basin
基金
中国科学院"西部之光"项目"西南喀斯特地区生态系统对极端天气气候的响应研究"(2060299)
关键词
高温天气
热浪
洞庭湖
风险
COPULA
extreme heat events
heatwave
Dongting Lake catchment
risk
copula
