暴雨灾害
暴雨災害
폭우재해
TORRENTIAL RAIN AND DISASTERS
2012年
1期
66-71
,共6页
长江中下游%梅雨锋暴雨%环流特征
長江中下遊%梅雨鋒暴雨%環流特徵
장강중하유%매우봉폭우%배류특정
the middle and lower reaches of Yangtze River%Meiyu front rainstrom%circulation characteristic
利用客观分析资料和常规观测资料,分析了2011年6月长江中下游梅雨锋暴雨的大尺度环流特征,并对其中两次梅雨锋暴雨过程的降水特征和锋生条件进行对比分析。结果表明：（1）500 hPa中高纬地区两槽一脊强度均比常年偏强,持续稳定的高纬经向环流形势的存在为梅雨锋强降水持续稳定提供了所需的冷空气,冷空气与印缅槽前稳定的西南气流在长江流域频繁交汇,有利梅雨锋锋生以及形成大范围持续性强降水;（2）200 hPa南亚高压北侧强西风急流以及其南侧东风急流均比常年明显偏强;（3）来自孟加拉湾的西南急流与副热带高压南侧偏强的东南气流辐合形成强南风影响我国华东地区,为梅雨锋强降水提供了充足的水汽输送,梅雨锋区水汽辐合明显加强时段与梅雨期四次强降水过程一一对应;（4）两次梅雨锋暴雨过程降水特征和锋生条件存在明显差异,前者冷暖空气同时对锋区作用造成能量锋区锋生,是一次对流性降水,后者无冷空气影响,是一次地面静止锋波动引起的稳定性降水。
利用客觀分析資料和常規觀測資料,分析瞭2011年6月長江中下遊梅雨鋒暴雨的大呎度環流特徵,併對其中兩次梅雨鋒暴雨過程的降水特徵和鋒生條件進行對比分析。結果錶明：（1）500 hPa中高緯地區兩槽一脊彊度均比常年偏彊,持續穩定的高緯經嚮環流形勢的存在為梅雨鋒彊降水持續穩定提供瞭所需的冷空氣,冷空氣與印緬槽前穩定的西南氣流在長江流域頻繁交彙,有利梅雨鋒鋒生以及形成大範圍持續性彊降水;（2）200 hPa南亞高壓北側彊西風急流以及其南側東風急流均比常年明顯偏彊;（3）來自孟加拉灣的西南急流與副熱帶高壓南側偏彊的東南氣流輻閤形成彊南風影響我國華東地區,為梅雨鋒彊降水提供瞭充足的水汽輸送,梅雨鋒區水汽輻閤明顯加彊時段與梅雨期四次彊降水過程一一對應;（4）兩次梅雨鋒暴雨過程降水特徵和鋒生條件存在明顯差異,前者冷暖空氣同時對鋒區作用造成能量鋒區鋒生,是一次對流性降水,後者無冷空氣影響,是一次地麵靜止鋒波動引起的穩定性降水。
이용객관분석자료화상규관측자료,분석료2011년6월장강중하유매우봉폭우적대척도배류특정,병대기중량차매우봉폭우과정적강수특정화봉생조건진행대비분석。결과표명：（1）500 hPa중고위지구량조일척강도균비상년편강,지속은정적고위경향배류형세적존재위매우봉강강수지속은정제공료소수적랭공기,랭공기여인면조전은정적서남기류재장강류역빈번교회,유리매우봉봉생이급형성대범위지속성강강수;（2）200 hPa남아고압북측강서풍급류이급기남측동풍급류균비상년명현편강;（3）래자맹가랍만적서남급류여부열대고압남측편강적동남기류복합형성강남풍영향아국화동지구,위매우봉강강수제공료충족적수기수송,매우봉구수기복합명현가강시단여매우기사차강강수과정일일대응;（4）량차매우봉폭우과정강수특정화봉생조건존재명현차이,전자랭난공기동시대봉구작용조성능량봉구봉생,시일차대류성강수,후자무랭공기영향,시일차지면정지봉파동인기적은정성강수。
Using the objective analysis data and observed rainfall,the large-scale circulation characteristics and the frontogenetical conditions of Meiyu front of the two intense rainstorm processes in the middle and lower reaches of Yangtze River in June 2011 are comparatively analyzed.The results are as follows：（1） the strength of two-ridge-one-trough on 500 hPa in middle and high latitudes regions was stronger than that in average years.Sustainable meridional circulation on high latitude provided the required cold air for Meiyu front rainstorm.The frequent intersection between cold air and the southwesterly flow from the Bay of Bengal was advantageous to the frontogenesis of Meiyu front and large-scale intense rainstorm.（2） The strength of westerly and easterly jets was obviously stronger than that in average years.（3） The southwesterly flow from the Bay of Bengal converged with the southeasterly flow which was on the southern periphery of the western Pacific subtropical high and formed the strong southerly flow providing sufficient water vapor for Meiyu front rainstorm.The periods of water vapor convergence corresponded to four intense rainstorm processes.（4） The precipitation characteristics and frontogenetical conditions of Meiyu front between the two intense rainstorm processes were obviously different.The joint action of cold and warm air caused the frontogenesis of Meiyu front in the former,whereas in the latter there was no cold air,and the precipitation was caused by stationary front wave.
