气象与环境学报
氣象與環境學報
기상여배경학보
JOURNAL OF METEOROLOGY AND ENVIRONMENT
2012年
5期
58-64
,共7页
暴雨%水汽输送%大气不稳定条件%急流%中尺度云团
暴雨%水汽輸送%大氣不穩定條件%急流%中呎度雲糰
폭우%수기수송%대기불은정조건%급류%중척도운단
The heavy rain%Water vapor transportation%Atmospheric instable condition%Jet stream%Mesoscale cloud mass
应用常规观测资料、NCEP再分析资料和卫星云图产品,对2011年7月31日黑龙江省西部暴雨天气成因进行诊断分析。讨论了产生暴雨的天气系统特征,大气不稳定条件及产生暴雨的水汽条件和动力触发机制。结果表明:暴雨是由低涡、低涡槽前暖湿气流与冷空气的共同影响产生的。低层强盛的偏南气流建立起水汽通道,将水汽源源不断地向暴雨区输送。低层增温增湿使得大气层结不稳定。低层较强的西北气流与强盛的东南暖湿气流汇合,产生强切变,辐合上升运动增强,为暴雨的产生提供了动力条件,有利于不稳定能量释放。高层辐散与低层辐合相配合,有利于上升运动发展和维持。地面中尺度低压和中尺度辐合线为中尺度云团的发展和维持提供了条件;中尺度云团在暴雨区旋转停留近21 h,这是暴雨发生的主要原因。
應用常規觀測資料、NCEP再分析資料和衛星雲圖產品,對2011年7月31日黑龍江省西部暴雨天氣成因進行診斷分析。討論瞭產生暴雨的天氣繫統特徵,大氣不穩定條件及產生暴雨的水汽條件和動力觸髮機製。結果錶明:暴雨是由低渦、低渦槽前暖濕氣流與冷空氣的共同影響產生的。低層彊盛的偏南氣流建立起水汽通道,將水汽源源不斷地嚮暴雨區輸送。低層增溫增濕使得大氣層結不穩定。低層較彊的西北氣流與彊盛的東南暖濕氣流彙閤,產生彊切變,輻閤上升運動增彊,為暴雨的產生提供瞭動力條件,有利于不穩定能量釋放。高層輻散與低層輻閤相配閤,有利于上升運動髮展和維持。地麵中呎度低壓和中呎度輻閤線為中呎度雲糰的髮展和維持提供瞭條件;中呎度雲糰在暴雨區鏇轉停留近21 h,這是暴雨髮生的主要原因。
응용상규관측자료、NCEP재분석자료화위성운도산품,대2011년7월31일흑룡강성서부폭우천기성인진행진단분석。토론료산생폭우적천기계통특정,대기불은정조건급산생폭우적수기조건화동력촉발궤제。결과표명:폭우시유저와、저와조전난습기류여랭공기적공동영향산생적。저층강성적편남기류건립기수기통도,장수기원원불단지향폭우구수송。저층증온증습사득대기층결불은정。저층교강적서북기류여강성적동남난습기류회합,산생강절변,복합상승운동증강,위폭우적산생제공료동력조건,유리우불은정능량석방。고층복산여저층복합상배합,유리우상승운동발전화유지。지면중척도저압화중척도복합선위중척도운단적발전화유지제공료조건;중척도운단재폭우구선전정류근21 h,저시폭우발생적주요원인。
Based on the conventionally observational data,the NCEP reanalysis data and satellite cloud image,the formation reasons of heavy rain weather on July 31,2011 in the west of Heilongjiang province were diagnosed.The weather system characteristics,atmospheric instable conditions,water vapor condition causing this process and dynamically triggering mechanism were discussed.The results indicate that the heavy rain is caused by the interaction of low vortex,warm-wet airflow in front of low vortex trough and cold air.The strong southerly airflow sets up a water vapor channel where water vapor can be transported to rainfall areas.The increase of temperature and humidity in the low level makes atmospheric stratification unstable.The strong northwest airflow converges with the strong southeast warm-wet airflow on low level and generates the strong wind shear,so convergence and ascending motion augment,which provide the dynamic condition for the heavy rain.At the same time,it is favorable to release the unstable energy.Upper divergence and lower convergence go together,which is favorable to the development and maintenance of ascending movement.Mesoscale low pressure and mesoscale convergence line on the ground provide the conditions for the development and maintenance of mesoscale cloud mass.The mesoscale cloud mass still stays about 21 hours in the areas of the heavy rain areas,which is the main reason causing the heavy rain.