摘要
城市和湖泊对区域降水都有显著的影响,但二者对暴雨过程的相对影响尚需定量评估。为了揭示城市与湖泊相对及共同作用对暴雨过程的影响,本文选取华东地区为研究区域,利用WRF模式,针对2015年6月27日一次江淮梅雨期间由低空切变线引发的暴雨过程,进行了敏感性试验对比研究。结果表明,太湖和周围城市的存在会增强研究区域的降水,并且城市的影响要大于太湖;太湖和周围城市与其他区域的温度差会导致地面风场在城市及其附近区域辐合,进而产生强对流;形成的强地面辐合线还会影响低空切变线的生成位置,并在其移动过程中相互调整、相互增强。总而言之,太湖与周围城市的共同作用对于地面风场辐合以及低空切变线的形成与强度都存在重要影响,进而影响本次暴雨的位置和强度。
Cities and lakes have obvious influences on regional precipitation,but their single or interaction effects on reginal heavy rain process remain to be quantified.To reveal the effects of interactions between cities and lakes on the process of heavy rain,this study focuses on a process of typical heavy rain induced by low-level shear line occurred on 27 June 2015 during Yangtze-Huaihe Meiyu period in East China,and conducts a serial of sensitivity experiments to explore the role of Lake Taihu and its nearby cities played in the heavy rain process.Through the contrast of elements in simulation results,it can be concluded that the coexistence of Lake Taihu and its nearby cities enhances the total precipitation of the study area,and the effects of nearby cities on increasing precipitation are more significant than Lake Taihu.The temperature differences between Lake Taihu and city area and the other areas cause the surface wind convergences around the cities,and then introduce strong convection.The strong surface convergence line can affect the form of low-level shear line as well,and it will adjust and enhance the low-level shear line with its movement.In conclusion,the interactions of Lake Taihu and its nearby cities have important influences on the formation and intensity of the surface wind convergence and lowlevel shear line,and then influence the location and strength of the heavy rain.
作者
李哲
高艳红
蒋盈沙
文莉娟
潘永洁
LI Zhe;GAO Yanhong;JIANG Yingsha;WEN Lijuan;PAN Yongjie(Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions,Northwest Institute of Ecology and Environmental Resources,Chinese Academy of Sciences,Lanzhou 730000,Gansu,China;Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences,Fudan University,Shanghai 200438,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《高原气象》
CSCD
北大核心
2022年第3期655-670,共16页
Plateau Meteorology
基金
国家重点研发计划项目(2017YFC1502101)。
关键词
华东地区
城市
湖泊
切变线
暴雨
East China
cities
lakes
shear line
heavy rain
