昆明城市降雨特性变化及城市热岛效应的可能影响  

Change of urban precipitation characteristics and the possible influence of urban heat island effect in Kunming

作　　者：金燕[1] 晏红明[1] 何雨芩[1] 任菊章[2] 张明达[1] 周群[3] Jin Yan;Yan Hongming;He Yuqin;Ren Juzhang;Zhang Mingda;Zhou Qun(Yunnan Climate Center,Kunming 650034,Yunnan,China;Yunnan Institute of Meteorological Science,Kunming 650034,Yunnan,China;Yunnan Meteorological Observatory,Kunming 650034,Yunnan,China)

机构地区：[1]云南省气候中心,云南昆明650034 [2]云南省气象科学研究所,云南昆明650034 [3]云南省气象台,云南昆明650034

出　　处：《地理科学》2024年第11期2039-2050,共12页Scientia Geographica Sinica

基　　金：云南省基础研究专项重点基金项目(202201AS070069);中国气象局气象能力提升联合研究专项(22NLTSZ005);云南省重点研发计划—社会发展专项(202203AC100006,202403AC100040);国家自然科学基金(42375043);中国气象局水文气象重点开放实验室开放研究课题(23SWQXZ008)资助。

摘　　要：利用1961—2020年昆明站和太华山站分钟降雨数据,通过对比昆明站不同最小降雨间隔的降雨场数、有效降雨量贡献率和自相关系数的变化,确定昆明地区合理的最小降雨间隔,划分降雨过程;在此基础上比较昆明城市和乡村降雨过程的不同变化,并分析导致城市降雨特性变化的可能原因,得到如下结论:(1)昆明以3 h为最小降雨间隔来划分自然降雨场次最为合理。(2)昆明地区有效降雨过程占40%,对总降雨量贡献率超95%;与乡村相比,城市年降雨场数在20世纪90年代后呈年代际变化特征,强降雨呈增加趋势。特别地,100.0 mm以上极强降雨增速远高于乡村。(3) 20世纪90年代后,昆明市区除微量降雨减少外,其余量级的降雨均有增加,城市降雨历时缩短,强降雨雨峰提前,降雨历时在1 h左右的强降雨由双峰雨型变为单峰雨型。(4)由气候变暖和城市面积扩展共同导致的城市热岛效应增强,致使下垫面温度升高,加速地表蒸发,改变了局地近地面对流活动与水汽条件,是导致昆明城市降雨特性变化的重要原因。Using the observation data of minute rainfall at Kunming Station from 1961 to 2020,the reasonable minimum rainfall interval in Kunming area was determined by comparing the changes in the number of rainfall fields,effective rainfall contribution rate,and autocorrelation coefficient distinguished by different minimum rainfall intervals at the station.On this basis,the minute rainfall observation data of the rural representative station(Taihuashan Station)was introduced to divide the rainfall processes of Kunming Station and Taihuashan Station with the minimum rainfall interval,to compare the different changes in urban and rural rainfall processes in Kunming City,and to analyze the possible reasons for the changes in urban rainfall characteristics.The following conclusions were drawn:1)The minimum rainfall interval for the natural rainfall process in Kunming area was set at 3 hours,which is the most reasonable.2)The effective rainfall process in Kunming area accounted for more than 40%of the total rainfall process,and the contribution rate of rainfall had exceeded 95%;Compared with rural areas,the number of annual rainfall events in urban areas has shown interdecadal changes since the 1990s,with an increasing trend of heavy rainfall,especially the growth rate of extremely heavy rainfall processes above 100.0 mm,which was much higher than in rural areas.3)After the 1990s,except for the decrease of trace rainfall,other rainfall in Kunming city has increased.The duration of urban rainfall was shortened and the peak of rainstorm was advanced.The heavy rainfall lasting about 1 hour changed from a bimodal rain pattern to a unimodal rain pattern.4)The intensification of urban heat island effect caused by climate change and urban expansion leads to an increase in underlying surface temperature,accelerated surface evaporation,local near surface convective activity,and changes in air moisture conditions,which were important reasons for the changes in rainfall characteristics in Kunming City.

关 键 词：城市降雨 降雨特性 城市热岛效应 

分 类 号：P461.3[天文地球—大气科学及气象学]