暴雨灾害
暴雨災害
폭우재해
TORRENTIAL RAIN AND DISASTERS
2013年
1期
38-45
,共8页
吴翠红%张萍萍%龙利民%王海燕%王珊珊%周金莲
吳翠紅%張萍萍%龍利民%王海燕%王珊珊%週金蓮
오취홍%장평평%룡이민%왕해연%왕산산%주금련
大暴雨%峡谷地形%冷暖空气%地形性涡旋
大暴雨%峽穀地形%冷暖空氣%地形性渦鏇
대폭우%협곡지형%랭난공기%지형성와선
extra heavy rainstorm%valley topography%cold and warm air%topographic vortex
利用湖北省加密自动站资料、常规观测资料、逐6 h的NCEP/GFS再分析资料以及FY2E红外卫星云图资料,对2012年6月29日、7月4日湖北省两次大暴雨过程中峡谷地形的增幅机制进行对比分析.结果表明:两次过程均在有利的背景场及环境条件下受三峡谷地特殊地形影响而产生,冷暖空气相互对峙并配合峡谷地形的阻挡作用,迫使近地层水平流场、垂直流场发生改变,同时流入峡谷的地面气流与复杂地形相互作用,在峡谷内产生局地气旋性小环流或气流汇合区,地形性涡旋的生成对降水增幅起到关键作用;两次过程的不同之处是,前一过程中,冷空气作用更显著、不稳定能量累积更多、峡谷地形增幅作用更复杂,其中包括狭管效应、喇叭口效应及迎风坡地形效应,所以其降水效率更高、雨强更大.
利用湖北省加密自動站資料、常規觀測資料、逐6 h的NCEP/GFS再分析資料以及FY2E紅外衛星雲圖資料,對2012年6月29日、7月4日湖北省兩次大暴雨過程中峽穀地形的增幅機製進行對比分析.結果錶明:兩次過程均在有利的揹景場及環境條件下受三峽穀地特殊地形影響而產生,冷暖空氣相互對峙併配閤峽穀地形的阻擋作用,迫使近地層水平流場、垂直流場髮生改變,同時流入峽穀的地麵氣流與複雜地形相互作用,在峽穀內產生跼地氣鏇性小環流或氣流彙閤區,地形性渦鏇的生成對降水增幅起到關鍵作用;兩次過程的不同之處是,前一過程中,冷空氣作用更顯著、不穩定能量纍積更多、峽穀地形增幅作用更複雜,其中包括狹管效應、喇叭口效應及迎風坡地形效應,所以其降水效率更高、雨彊更大.
이용호북성가밀자동참자료、상규관측자료、축6 h적NCEP/GFS재분석자료이급FY2E홍외위성운도자료,대2012년6월29일、7월4일호북성량차대폭우과정중협곡지형적증폭궤제진행대비분석.결과표명:량차과정균재유리적배경장급배경조건하수삼협곡지특수지형영향이산생,랭난공기상호대치병배합협곡지형적조당작용,박사근지층수평류장、수직류장발생개변,동시류입협곡적지면기류여복잡지형상호작용,재협곡내산생국지기선성소배류혹기류회합구,지형성와선적생성대강수증폭기도관건작용;량차과정적불동지처시,전일과정중,랭공기작용경현저、불은정능량루적경다、협곡지형증폭작용경복잡,기중포괄협관효응、나팔구효응급영풍파지형효응,소이기강수효솔경고、우강경대.
@@@@Based on intensive automatic weather station observations in Hubei, conventional surface and upper data, 6-hourly reanalysis da-ta form NCEP and FY-2E infrared satellite images, a comparative analysis is made on enhancement mechanism of valley topography to two heavy rainstorms events occurred respectively on 29 June and on 4 July 2012. The results show that both heavy rainstorms occur in advanta-geous circulation patterns and environment conditions and are affected by valley topography in Yangtze River Three Gorges. Confronting of cold and warm air and coordinating with resistance effect from valley topography force the horizontal and vertical flow fields near the ground changed, meanwhile, the interaction between the ground airflow flowing into gorges and the complicated topography leads to a local cyclone micro-circulation or convergence zone in the gorges. As a result the formation of topographic vortexes plays a crucial role to increase precipi-tation. The difference between the two events is that in the former event, cold air has more significant effect, more instable energy is accumu-lated and more complicated enhancement of valley topography exists including the narrow-tube effect, bell mouthed topographic effect and windward slope effect, so that this event has more efficient precipitation and higher rainfall intensity.