摘要
利用1984—2010年四川地区暴雨致灾经济损失调查表以及1981—2010年6—9月四川地区逐日降水资料和NCEP再分析资料,探讨了暴雨洪涝年和干旱少雨年的影响环流系统的差异,结果表明:2000—2010年暴雨致灾经济损失较前10年增加了80.6%,致灾暴雨发生站次增加了38%。致灾洪涝年暴雨发生的6—9月环流背景特征是:南亚高压在"西涝东旱"年环流比"东涝西旱"年偏强;副高586dagpm位于四川和重庆以南的地区。洪涝年7月开始副高有明显的准双周左右的振荡周期,西风环流指数较干旱年波动较大,对流层中高层东亚中高纬大气环流出现14天左右的低频振荡,高原低涡具有14天左右的振荡周期。低纬度西南气流多次向中高纬输送,孟湾地区水汽通量较常年偏强,且进入四川地区的水汽通道通畅。
Based on the Sichuan rainstorm hazard and economic loss survey from 1984 to 2010,the daily precipitation data,and NCEP reanalysis data from June to September,1981 to 2010in Sichuan,the characteristics of economic loss induced by rainstorm hazard for nearly 30 years are studied and the multiscale circulation background in Sichuan rainstorm hazard is obtained.The results show that rainstorminduced economic losses from 2000 to 2010over the previous 10 years increased by 80.6%,and the occurrence frequency of rainstorm hazard increased by 38%.The characteristics of rainstorm circulation background form June to September are：South Asia High is stronger in the year offlooding in west and drought in east ＂than in the year offlooding in east and drought in west＂;the 586 line of Western Pacific Subtropical High is located in the south of Sichuan and Chongqing;in flood years,Subtropical High has significantly quasi-biweekly oscillation cycle from the beginning of July,and the volatility of westerly circulation index is greater.In the middle and upper troposphere at high latitudes,the East Asia atmospheric circulation has a 14-day LFO（Low Frequency Oscillation）;the Plateau vortex has about 14-day turbulence cycle;the southwest flow at low latitudes repeatedly is delivered to high latitudes,and the Bay of Bengal vapor flux is stronger than normal;and the vapor passage into the Sichuan region is unobstructed.
出处
《气象科技》
北大核心
2016年第3期408-415,共8页
Meteorological Science and Technology
基金
川气课题(2015-青年-07)
川气课题(2014-成果-03)资助
关键词
暴雨致灾
影响环流系统
低频振荡
热带季风涌
rainstorm hazard
circulation system
LFO（Low Frequency Oscillation）
tropical monsoon surge
