0605号台风“格美”在江西致灾的气象成因分析

Analysis of the Meteorological Reason of Typhoon KAEMI Damaging Jiangxi Province

运用常规观测资料、T213资料等,对0605号台风“格美”的移动路径和暴雨成因进行了分析。分析结果表明,“格美”登陆后虽然强度迅速减弱,但由于其减弱后的低气压环流在江西逗留时间长,所携带的水汽和造成的辐合上升条件足以造成江西出现暴雨天气。通过分析探空、地面加密自动站和闪电定位等资料进一步指出,地面中尺度辐合线、对流不稳定和地形抬升的共同作用,加剧了赣西南局地降雨的强度。由于前期台风“碧利斯”已造成赣州市出现较强降水,赣南土壤含水量、地下水位和江河湖库水位均较高,使得“格美”造成的短时强降雨迅速产生有效径流和汇流,导致局地山洪暴发而致灾。

With routine observation data, movement path and torrential rain mason of Typhoon KAEMI are analyzed. Because of long time continuance in Jiangxi oflower pressure from weakened KAEMI, conditions of water vapor and convergence ascending are salutary to occurrence of torrential rain, though Typhoon KAEMI is weakened rapidly after landing. After analyzing more data of sounding, dense surface automatic Meteorological stations and lightening location, we find that common effects of surface mesoscale convergence line, convective instability and terrain uplifting make the intensity of rainfall increased in west-south of Jiangxi province. Because of effect of former severe tropical storm BILIS, soil water content, underground water level and that of rivers and reservoirs of the south of Jiangxi province are in high level. So short time of strong rainfall rapidly produce effective runoff and accordant junction, then local flash flood break out.