热带农业科学
熱帶農業科學
열대농업과학
CHINESE JOURNAL OF TROPICAL AGRICULTURE
2011年
5期
50-57
,共8页
秋季暴雨%天气分析%能量锋%湿有效位能%差动%平流
鞦季暴雨%天氣分析%能量鋒%濕有效位能%差動%平流
추계폭우%천기분석%능량봉%습유효위능%차동%평류
rainstorm in autumn%weather analysis%energy front%moist available potential energy%vertically differential%advection
对海南岛2000年和2008年两次秋季暴雨的特性和影响系统的分析发现:暴雨的发生、维持和消失主要与大陆冷高、南海低值系统、热带云团活动密切相关,暴雨一般与华南沿海的低空偏东风急流相伴。对流层中层正差动涡度平流和副高南侧的暖平流破坏了海南岛及邻近区域的准地转平衡,动力强迫和热力强迫共同作用激发了次级环流,导致暴雨区上空的垂直运动的发展,促使暴雨增强。对流层中层干冷空气的侵入,正的差动假相当位温平流加剧了大气层结的不稳定,强的风垂直切变更促使对流上升运动的发展,这对暴雨局地的再增强起到了重要作用。可以综合提出海南岛秋季暴雨天气的预报着眼点,为海南岛秋季暴雨天气潜势预报和临近预报提供线索。
對海南島2000年和2008年兩次鞦季暴雨的特性和影響繫統的分析髮現:暴雨的髮生、維持和消失主要與大陸冷高、南海低值繫統、熱帶雲糰活動密切相關,暴雨一般與華南沿海的低空偏東風急流相伴。對流層中層正差動渦度平流和副高南側的暖平流破壞瞭海南島及鄰近區域的準地轉平衡,動力彊迫和熱力彊迫共同作用激髮瞭次級環流,導緻暴雨區上空的垂直運動的髮展,促使暴雨增彊。對流層中層榦冷空氣的侵入,正的差動假相噹位溫平流加劇瞭大氣層結的不穩定,彊的風垂直切變更促使對流上升運動的髮展,這對暴雨跼地的再增彊起到瞭重要作用。可以綜閤提齣海南島鞦季暴雨天氣的預報著眼點,為海南島鞦季暴雨天氣潛勢預報和臨近預報提供線索。
대해남도2000년화2008년량차추계폭우적특성화영향계통적분석발현:폭우적발생、유지화소실주요여대륙랭고、남해저치계통、열대운단활동밀절상관,폭우일반여화남연해적저공편동풍급류상반。대류층중층정차동와도평류화부고남측적난평류파배료해남도급린근구역적준지전평형,동력강박화열력강박공동작용격발료차급배류,도치폭우구상공적수직운동적발전,촉사폭우증강。대류층중층간랭공기적침입,정적차동가상당위온평류가극료대기층결적불은정,강적풍수직절변경촉사대류상승운동적발전,저대폭우국지적재증강기도료중요작용。가이종합제출해남도추계폭우천기적예보착안점,위해남도추계폭우천기잠세예보화림근예보제공선색。
By comprehensive analysis the climate characteristics and the influencing systems on rainstorm in Autumn of Hainan Island,it's found that: storm rainfall out-breaking,maintaining and weakening has something to do with the continental cold high,low system above the South China Sea and tropical cloud clusters.Storm rainfall is often accompanied with low-level easterly jet at the coastal South China.In the middle troposphere,the positive vertically differential vorticity advection and the warm advection to the south of the Western Pacific Sub-tropical High destroy the quasi-geostrophic balance in the Hainan Island and its neighborhood.The secondary circulation is present by the interaction of dynamical and thermal forcing,result in vertical motion and heavy rain.The unstable stratification is intensified by the dry cold air intrusion in the middle troposphere and the advection of positive differential pseudo-equivalent potential temperature.The strong vertical shear of wind also enhanced the development of convective ascending motion further,and is in favor of the intensification of storm rainfall.These characters can be summarized to form ideas for forecasting the NON-Typhoon storm rainfall in Autumn,so as to serve the potential and nowcasting forecasts of strong convective weathers in Hainan Island.