热带海洋的降水区域划分及相关大气背景环境特征  

Regionalization of precipitation and associated atmospheric background environmental characteristics over the tropical oceans

作　　者：纪献普 沙雨星 冯涛 李俊杰 JI Xianpu;SHA Yuxing;FENG Tao;LI Junjie(Key Laboratory of Marine Hazards Forecasting,Ministry of Natural Resources,Hohai University,Nanjing 210098,China;College of Oceanography,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学自然资源部海洋灾害预报技术重点实验室,江苏南京210098 [2]河海大学海洋学院,江苏南京210098

出　　处：《厦门大学学报（自然科学版）》2024年第3期492-503,共12页Journal of Xiamen University：Natural Science

基　　金：国家自然科学基金(42175063)。

摘　　要：[目的]探究热带海洋上空的大气背景环境差异对降水特征的影响及其内在机制.[方法]使用1998—2013年热带降雨测量任务(TRMM)的逐月降水特征数据,利用聚类分析的方法将热带降水区域划分为5种典型类型,并通过湿静能(MSE)和对流有效位能(CAPE)等诊断变量探讨不同降水类型与大气背景环境之间的关系.[结果]研究发现以西太平洋暖池为代表的强降水区域表现出强烈的垂直运动和水汽背景.相反地,大陆副热带西岸等区域由于下沉异常和相对较干的大气条件,降水较为微弱.其他开放大洋区域的降水受水汽异常和大气稳定性影响,较低的稳定度和更湿的中低层大气有利于形成高空降水.[结论]本研究探讨了热带海洋上空大气背景环境与降水类型之间的关系,指出大尺度气候背景的动力热力作用对热带海洋上空降水类型的关键影响,有助于加深对热带海洋上空降水空间分布的理解.[Objective]Precipitation over tropical oceans plays a crucial role in the global energy and water cycle.The oceans provide moisture to the atmosphere through evaporation,and precipitation forms through the condensation of water vapor in the atmosphere.The release of latent heat during the formation of precipitation is a major driver of atmospheric circulation,influencing weather systems and cloud formation.However,there are large differences in the background environments over the tropical oceans.How these differences affect precipitation characteristics and the intrinsic mechanisms involved remain to be investigated.[Methods]In this study,monthly precipitation characterization data from the Tropical Rainfall Measuring Mission(TRMM)spanning from 1998 to 2013 are utilized,including convective precipitation rates,stratiform precipitation rates,convective storm heights,and stratiform storm heights.The European Center for Medium-Range Weather Forecasts fifth generation reanalysis monthly data(ERA5)are also used in this study to provide the atmospheric background environment field.Tropical precipitation regions are classified into five typical types using cluster analysis.The relationship between precipitation types and atmospheric environments is explored through diagnostic variables such as moist static energy and convective available potential energy.[Results]This study elucidates the underlying causes of different precipitation types within critical tropical regions through the perspective of large-scale atmospheric background environments and moist static energy.Notably,precipitation distribution across tropical oceans displays marked spatial heterogeneity,gradually diminishing from the tropics towards extra-equatorial regions.The study classifies the five precipitation types into categories of strong upwelling areas,strong subsidence areas,and weak upwelling zones based on vertical motion profiles.Notably,regions such as the western Pacific warm pool are characterized by robust convective precipitation due to fa

关 键 词：热带 对流降水 层状降水 风暴高度 湿静能 

分 类 号：P47[天文地球—大气科学及气象学]