登陆台风“杰拉华”与“海葵”降雨差异的水汽输送特征

Characteristics of water vapor transport in precipitation difference between two landing typhoons of "Jelawat" and "Haiku"

利用水平分辨率1.0°×1.0°的美国国家环境预报中心(National Centers for Environmental Prediction,NCEP)再分析资料、水平分辨率为2.5°×2.5°的美国国家海洋和大气管理局(National Oceanic and Atmospheric Administration,NOAA)大气环流资料、水平分辨率为1.0°×1.0°的NCEP全球资料同化系统(Global Data Assimilation System,GDAS)资料,结合拉格朗日混合单粒子轨迹模式(Hybrid Single Particle Lagrangian Integrated Trajectory Model,HYSPLIT)对两个路径相似但降雨分布存在较大差别的登陆台风"杰拉华"和"海葵"进行水汽输送对比分析,并进一步探讨水汽对于台风"海葵"登陆减弱后引发暴雨增幅的影响。结果表明:登陆后台风"海葵"维持时间和风雨的影响明显强于"杰拉华";陆地上输送的水汽(59.9%)是台风"杰拉华"的主要的水汽通道,但得不到暖洋面上的水汽补充,迫使其快速衰亡,降雨强度也较弱;而台风"海葵"登陆后,南海和黄海依然为其提供了大部分的水汽,台风"海葵"登陆后的水汽来源可以分为两类,一类为直接从洋面进入雨区的偏东水汽,另一类为与热带气旋(Tropical Cyclones,TC)环流相联系的偏南水汽。台风"海葵"登陆后第一轮暴雨的水汽主要来源于日本以东洋面(61.2%),南海水汽输送在一定程度上促进了第二轮暴雨的增强。江苏南部地区降雨的水汽主要来源于东海和中国东部地区(46.3%),中国东部地区蕴含的水汽和能量低于暖洋面,运行过程中携带的水汽量逐渐减少,可能是江苏南部地区降雨强度偏弱的原因之一。

Based on the reanalysis data with a spatial resolution of 1.0°×1.0° from the National Centers for Environmental Prediction （NCEP）,the atmospheric circulation data of 2.5°×2.5° from the National Oceanic and Atmospheric Administration （NOAA） and the assimilation data of 1.0°×1.0° from the Global Data Assimilation System （GDAS）,and using the Hybrid Single Particle Lagrangian Integrated Trajectory （HYSPLIT） Model,the characteristics of water vapor transport were analyzed for two landing typhoons ＂Jelawat＂ and ＂Haikui＂ that had similar tracks but large difference in precipitation distributions and the effect of water vapor on increase of heavy rainfall after landing weakness of the ＂Haikui＂ typhoon was discussed.The results showed that the maintenance duration and precipitation of ＂Haikui＂ after landing are stronger than those of ＂Jelawat＂ after landing.Water vapor transported from the inland （59.9%） plays an important role for ＂Jelawat＂.Without water supplement from the ocean,＂Jelawat＂ declines rapidly and the precipitation intensity decreases.After the landing of ＂Haikui＂,water vapor is mostly transported from the South China Sea and Yellow Sea,which can come from two paths,one from the eastern ocean surface that travels directly into the rainfall area and the other from the southern region related to the tropical cyclone （TC） circulations.Water vapor during the first heavy precipitation event after the landing of ＂Haikui＂ is mainly coming from the ocean in the east of Japan （61.2%）,and water vapor transported from the South China Sea contributes the enhancement of the second heavy precipitation event to a certain extent.Water vapor during precipitation in the southern region of Jiangsu province is mainly from the East China Sea and East China （46.3%）.Water vapor and energy in the East China are both smaller than those from the southern warm ocean,and water vapor decreases gradually during long distance transportation,which probably results in the weak precipitation in the southern region of Jiangsu province.