气象科学
氣象科學
기상과학
SCIENTIA METEOROLOGICA SINICA
2010年
1期
67-73
,共7页
何锋%何斌%李云泉%范晓红%董旭
何鋒%何斌%李雲泉%範曉紅%董旭
하봉%하빈%리운천%범효홍%동욱
暴雨%数值模拟%低涡
暴雨%數值模擬%低渦
폭우%수치모의%저와
Rainstorm%Numerical simulation%Low vortex
用WRF模式对2007年4月21-22日的一次中α低涡暴雨过程进行了高分辨率模拟,结果表明:(1)该低涡的产生与湖北西部的地形条件有一定的联系,低压倒槽系统为其提供了必要的环流背景,反演自FY-2 C卫星的TBB资料较好地反映了该中α低涡的整个活动过程.(2)对低涡发展最强阶段的动力和热力结构分析表明,低涡右侧为较强的上升运动,而其左侧则为下沉运动,在中低层冷空气上部有南侧暖湿空气上爬造成的次级上升运动;低涡左侧存在较明显的湿斜压锋区,后部则有明显的干冷气切入;南风风量对总体水汽输送的贡献要大于西风风量.(3) WRF模式中NOAH和热扩散陆面方案的对比分析表明,NOAH方案更加有利于低涡中心的发展,因此能够产生较热扩散方案更强的中心区降水,但是这种增强作用主要分布在低涡区附近,其他地区差别不大.
用WRF模式對2007年4月21-22日的一次中α低渦暴雨過程進行瞭高分辨率模擬,結果錶明:(1)該低渦的產生與湖北西部的地形條件有一定的聯繫,低壓倒槽繫統為其提供瞭必要的環流揹景,反縯自FY-2 C衛星的TBB資料較好地反映瞭該中α低渦的整箇活動過程.(2)對低渦髮展最彊階段的動力和熱力結構分析錶明,低渦右側為較彊的上升運動,而其左側則為下沉運動,在中低層冷空氣上部有南側暖濕空氣上爬造成的次級上升運動;低渦左側存在較明顯的濕斜壓鋒區,後部則有明顯的榦冷氣切入;南風風量對總體水汽輸送的貢獻要大于西風風量.(3) WRF模式中NOAH和熱擴散陸麵方案的對比分析錶明,NOAH方案更加有利于低渦中心的髮展,因此能夠產生較熱擴散方案更彊的中心區降水,但是這種增彊作用主要分佈在低渦區附近,其他地區差彆不大.
용WRF모식대2007년4월21-22일적일차중α저와폭우과정진행료고분변솔모의,결과표명:(1)해저와적산생여호북서부적지형조건유일정적련계,저압도조계통위기제공료필요적배류배경,반연자FY-2 C위성적TBB자료교호지반영료해중α저와적정개활동과정.(2)대저와발전최강계단적동력화열력결구분석표명,저와우측위교강적상승운동,이기좌측칙위하침운동,재중저층랭공기상부유남측난습공기상파조성적차급상승운동;저와좌측존재교명현적습사압봉구,후부칙유명현적간랭기절입;남풍풍량대총체수기수송적공헌요대우서풍풍량.(3) WRF모식중NOAH화열확산륙면방안적대비분석표명,NOAH방안경가유리우저와중심적발전,인차능구산생교열확산방안경강적중심구강수,단시저충증강작용주요분포재저와구부근,기타지구차별불대.
WRF model is used to simulate meso-α vortex rainstorm of 21-22 Apr. 2007. The results indicate that (1) The genesis of the vortex relates with the terrain condition in the west of Hubei province to some extent. The low pressure trough system provides necessary circulation background for it. The TBB data retrieved from FY-2C satellite reflected the entire activities of the meso-α vortex. (2) Analysis on the thermal-dynamic structure of the vortex in its strongly developing phase indicates that there is strong ascending motion on its right side, while sinking motion on its left side. Warm and moist air climbes upon the cold air at the mid-low level which forms the secondary upward movement. On the left side of the vortex exists an obvious barocline frontal zone and dry cold air enters into the back vortex. The southerly component of wind makes more contribution to moist transportation than the westerly component of wind. (3) Comparing NOAH LSM scheme with thermal diffusion one in WRF moel, it is indicated that NOAH scheme is beneficial to vortex center deepening, so it can produce more precipitation. Such enhancement mainly distributes around the vortex, while there is no obvious difference in other areas.