云辐射效应对一次高原低涡过程影响的数值模拟研究  

Numerical Simulation on the Influence of Cloud Radiation Effect on a Case of Tibetan Plateau Vortex

作　　者：陈逸豪 范广洲 Chen Yihao;Fan Guangzhou(School of Atmospheric Sciences/Plateau Atmosphere and Environment Key Laboratory of Sichuan Province/JointLaboratory of Climate and Environment Change,Chengdu University of Information Technology,Chengdu 610225)

机构地区：[1]成都信息工程大学大气科学学院/高原大气与环境四川省重点实验室/气候与环境变化联合实验室,成都610225

出　　处：《气象科技进展》2021年第4期102-112,共11页Advances in Meteorological Science and Technology

基　　金：国家重点研发计划(2018YFC1505702);第二次青藏高原综合科学考察研究(2019QZKK0102)。

摘　　要：利用NCEP-FNL再分析资料、FY-2G卫星相当黑体亮温TBB数据,通过WRF(V3.8.1)模式对2015年8月5—7日的一次高原低涡过程进行了4组模拟试验,研究了云辐射效应对高原低涡过程的影响。结果表明,云辐射效应主要通过改变云区的辐射分布影响大气稳定度,从而影响高原低涡的发展和结构。在低涡生成阶段,白天云辐射加热抑制低涡南侧的对流,从而有利于水汽和动量向低涡源地输送;夜间云顶长波冷却促进涡区的对流活动,有利于低涡的发展。低涡成熟阶段中,涡心及其周围区域夜间辐射冷却的水平和垂直分布利于涡心下沉、外围上升的垂直运动分布,并与云辐射效应构成正反馈过程,有利于涡眼结构的形成。在低涡快速东移阶段中,云辐射加热和冷却的昼夜变化调节着低涡的强度和东移速度,而当低涡东移出高原后,这种作用则变得不显著。Using the National Centers for Environmental Predication Final Analyses(NCEP-FNL)reanalysis data and the temperature of brightness blackbody(TBB)data from FY-2G meteorological satellite,four sets of simulation experiments were carried out on a Tibetan Plateau Vortex process from August 5 to 7,2015 through WRF model(Version 3.8.1).The influence of cloud radiation effects on the Tibetan Plateau Vortex is studied.The results show that the cloud radiation effect mainly affects the stability of the atmosphere by changing the radiation distribution of the cloud area,thereby affecting the development and structure of the Tibetan Plateau Vortex.In the developing stage,the cloud radiation heating during the daytime suppresses the convection on the south side of the vortex,which facilitates the transportation of water vapor and momentum to the source region of the low vortex.The long-wave cooling of the cloud top at night promotes the convective activity in the vortex area,which is beneficial to the development of the vortex.In the mature stage,the horizontal and vertical distribution of night-time radiation cooling of the vortex core and its surrounding area is conducive to the vertical motion distribution of the vortex core sinking and the periphery rising.And it forms a positive feedback process with the cloud radiation effect,which is conducive to the formation of the vortex eye structure.During the rapid eastward movement of the low vortex,the diurnal changes in cloud radiation heating and cooling regulate the intensity and eastward movement speed of the vortex.When the vortex moves eastward,this effect becomes insignificant.

关 键 词：青藏高原 高原低涡 云辐射效应 数值模拟 

分 类 号：P458.12[天文地球—大气科学及气象学]