###
气象:2017,43(11):1339-1353
本文二维码信息
码上扫一扫!
2014年两次相似路径影响云南台风降水差异成因分析
梁红丽1,程正泉2
(1 云南省气象台,昆明 650034 2 广州中心气象台,广州 510080)
Cause Analysis of Precipitation Difference Between Two Typhoons Influencing Yunnan Along Similar Tracks in 2014
LIANG Hongli1,CHENG Zhengquan2
(1 Yunnan Meteorological Observatory, Kunming 650034 2 Guangzhou Central Meteorological Observatory, Guangzhou 510080)
摘要
图/表
参考文献
相似文献
本文已被:浏览 514次   下载 285
投稿时间:2016-02-04    修订日期:2017-02-24
中文摘要: 2014年台风威马逊和海鸥沿偏西路径影响云南,大到暴雨分布特征与热带气旋相对位置存在显著差异。诊断结果表明,暴雨分布差异的产生主要是环境场气流的作用,造成锋生以及能量变化的差异,再加之地形作用。具体地,“威马逊”台风中心南(北)侧低层西风(东风)急流及辐合增强,造成了强降水的产生,但是由于南侧低层水汽含量大于北侧,且南侧滇西南边缘、红河河谷迎风坡对增强气流的抬升作用,降水增幅,以致南侧降水强于北侧;再者,南北两侧气流热力性质的差异造成了锋生,低层锋区增强也有利于“威马逊”东北侧、滇东南强降水发展;进一步地,东西风交汇辐合作用增强、斜压有效位能的释放,造成辐散风动能增加,暴雨区辐散风动能的增加与“威马逊”降水峰值变化相对应。“海鸥”影响云南期间,热带气旋中心位置和孟加拉湾低压均偏南,西南季风偏南,影响云南的主要是“海鸥”东北侧低空急流,且急流及其左前侧纬向辐合均强于“威马逊”,以致于其东北侧降水强于“威马逊”;除此之外,地形抬升对滇南边缘大暴雨的产生也起着重要作用;再者,低层锋区增强,有利于“海鸥”东北侧滇东北强降水发展;进一步地,旋转风动能的增加与降水峰值相对应,滇中以东地区第一次降水峰值与斜压过程相联系;第二次降水峰值的形成,则主要是低压倒槽东侧偏南急流增强,旋转风场向暴雨区输送动能,暴雨区动能明显增幅,与正压过程相联系。
Abstract:Typhoons Ramasun and Kalmaegi along west route influenced Yunnan in 2014, where rainstorm distribution characteristics and the relative position of tropical cyclone had significant differences. The diagnosis results indicate that production of rainstorm distribution difference was mainly caused by the role of ambient flow field, which caused frontogenesis, then energy change, together with the effect of topo graphy. Particularly, low level westerly (easterly) jet and convergence at south (north) side of Ramasun Typhoon center enhanced, causing generation of heavy rainfall. However, because water vapor content in lower layer of south side was higher than that of north side, the southwest Yunnan edge and Red River Valley windward slope had uplift effect, the rainfall amplified. Precipitation of south side was heavier than that of north side. In addition, thermodynamic properties differences of flow between south and north side caused frontogenesis. Frontal zone at low level enhanced, beneficial to the development of severe precipitation on the northeastern side of Ramasun, southeast Yunnan. Furthermore, intersection of the easterly and westerly made divergence enhancing, then baroclinic available potential energy was released, which caused divergent wind kinetic energy to increase, and increase of divergent wind kinetic energy was relative to the change of precipitation peak caused by Ramasun. However, as Kalmaegi was influencing Yunnan, the center position of tropical cyclone and Bay of Bengal low pressure were both further south, and the southwest monsoon was also further south. The low level jet at Kalmaegi northeastern side was the main factor influencing rainfall over Yunnan, and the intensity of low level jet and zonal convergence at the jet front left quadrant were both stronger than that by Ramasun, so the precipitation of Kalmaegi northeastern side was more intense than that of Ramasun. In addition, the uplift effect of terrain played an important role in the generation of heavy rainstorm at south Yunnan edge. Moreover, frontal zone at low level enhanced, which was also beneficial to the development of severe precipitation over northeast Yunnan at the northeastern side of Kalmaegi. Furthermore, increasing rotational wind kinetic energy was relative to precipitation peak, and the formation of the first precipitation peak in the edom of central Yunnan was related to baroclinic processes. However, at the second precipitation peak, south jet was strengthened on the east side of depression inverted trough, and rotational velocity field transported kinetic energy to heavy rain area, then kinetic energy over heavy rain area increased significantly, which was related to barotropic processes.
文章编号:     中图分类号:P458    文献标志码:
基金项目:国家自然科学基金项目(41365007和41365006)共同资助
引用文本:
梁红丽,程正泉,2017.2014年两次相似路径影响云南台风降水差异成因分析[J].气象,43(11):1339-1353.
LIANG Hongli,CHENG Zhengquan,2017.Cause Analysis of Precipitation Difference Between Two Typhoons Influencing Yunnan Along Similar Tracks in 2014[J].Meteor Mon,43(11):1339-1353.