CAJ | 학술논문

2010年前汛期末期中国华南出现暴雨过程，暴雨在华南西部与东部有不同影响，利用NCEP再分析资料和常规观测资料，分析此次暴雨特征与机理。结果表明：对中国华南地区整体而言，暴雨期间高层受南亚高压东南伸弱脊辐散区影响；中层副热带高压西伸脊先东退、后西伸；暴雨区位于低层相当位温锋区南侧、气流辐合；边界层偏南风急流形成后暴雨发生。分区而言，华南西部两次出现各持续1d的多站点暴雨时期；每次暴雨站数明显增加，较之前低层能量大、中低层层结不稳定且整层大气可降水量大；两个多站点暴雨日期之间边界层中尺度偏南风急流有两次明显减弱，低层水汽辐合与上升运动发生明显中断。华南东部多站点暴雨只出现一次但持续3 d，虽然在暴雨前期3个指数条件均没有西部两次暴雨前期好，但是连续3 d多站点暴雨期间较大尺度偏南风边界层急流基本维持，低层水汽辐合与上升运动没有发生明显中断，导致了东部暴雨站点多、强度大及持续时间长。因此，对于华南前汛期暖区暴雨而言，边界层偏南风急流的生消活动与水平尺度均较重要。
2010년전신기말기중국화남출현폭우과정，폭우재화남서부여동부유불동영향，이용NCEP재분석자료화상규관측자료，분석차차폭우특정여궤리。결과표명：대중국화남지구정체이언，폭우기간고층수남아고압동남신약척복산구영향；중층부열대고압서신척선동퇴、후서신；폭우구위우저층상당위온봉구남측、기류복합；변계층편남풍급류형성후폭우발생。분구이언，화남서부량차출현각지속1d적다참점폭우시기；매차폭우참수명현증가，교지전저층능량대、중저층층결불은정차정층대기가강수량대；량개다참점폭우일기지간변계층중척도편남풍급류유량차명현감약，저층수기복합여상승운동발생명현중단。화남동부다참점폭우지출현일차단지속3 d，수연재폭우전기3개지수조건균몰유서부량차폭우전기호，단시련속3 d다참점폭우기간교대척도편남풍변계층급류기본유지，저층수기복합여상승운동몰유발생명현중단，도치료동부폭우참점다、강도대급지속시간장。인차，대우화남전신기난구폭우이언，변계층편남풍급류적생소활동여수평척도균교중요。
A heavy rain took place at the end of the first rainy season of 2010 in the South China,and this process in the west was different from that in the east.By applying the NCEP reanalysis data,conventional observation da-ta,characteristics and mechanisms of the heavy rain were analyzed.The results show that as a whole,main influen-cing system at high levels over the Southern China is a weak ridge stretching southeast from South Asia High,and the air flow there is divergent.Middle level ridge stretching westward from Subtropical High retreats eastward first-ly,and then moves westward.Once boundary layer jet forms,the heavy rain appears in the south of equivalent po-tential temperature front at low level,and stream convergence takes place.For different divisions,the heavy rain occurs at many stations simultaneously twice in the west of South China,and it lasts 1 day every time.Averaged indexes calculated using the radiosonde stations data show that 850 hPa equivalent potential temperature and pre-cipitable water vapor are large,and stratification in the middle and low levels is very unstable before the number of stations with the heavy rain increases significantly in the west.Boundary layer jet weakens obviously twice over the west of South China between the two days when heavy rain takes place at many stations simultaneously.Between the two days of multiple heavy rain sites in the west,both upward movement and water vapor convergence in low level is interrupted obviously.It is only one time for the heavy rain event of many stations simultaneously in the east of South China,while it lasts for 3 days.The 3 indexes mentioned above are all not very favorable for the in-crease of number of heavy rain stations,although boundary layer jet maintains over the east of South China during the three days,and water vapor convergence and upward motion at low level are not interrupted.Thus this precipi-tation in the east is characterized with large areas,strong intensity and long duration.Generation or disappearance of southerly boundary layer jet and horizontal scale are crucial to heavy rain in the first rainy season in the South China.