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投稿时间:2014-05-23 修订日期:2014-10-08
投稿时间:2014-05-23 修订日期:2014-10-08
中文摘要: 1311号强台风尤特登陆后给广东带来持续性大范围强降水,对流降水特征十分显著。文章分析了“尤特”影响期间大尺度环流背景,重点讨论了此次持续性强降水过程中大气层结问题。发现低空急流向广东输送强的暖平流,是广东大气层结不稳定得以持续维持的根本原因。进一步分析发现,低空急流本身并不是“暖”的,当“尤特”趋向陆地时,陆地上的暖气团在“尤特”环流强迫下向南传播扩散,低空急流穿越这一暖区时温度升高才具备“暖”的特性。温度诊断方程结果进一步证实这一点。通过个例反查,在许多登陆后造成连续强降水的台风过程中均发现了这一特征。因此,台风登陆引起环境温度场的演变以及与低空急流的配置需引起业务预报上的重视。
中文关键词: 台风尤特, 强降水, 层结, 暖平流, 低空急流
Abstract:Severe Typhoon Utor (No.1311) brings sustained heavy rainfall with extremely strong convective storms to Guangdong after it makes landfall. Based on the observation and the NCAR FNL data, characteristics of large scale circulation, especially of the atmospheric stratification during the extreme event are studied. It is found that, the maintenance of the instable stratification is mainly due to the warm advection to Guangdong transferred by the low level jet. Further study reveals a truth that, the low level jet, originally cold over the sea, is warmed and blows to Guangdong when it moves across a warm air mass, which is forced from the land to the upstream region of Guangdong by the outer circulation of “Utor” while it is approaching Guangdong. The result of temperature diagnosis function confirms it. Similar phenomena are found in many cases which result in sustained torrential rain events after typhoons land. Therefore, the variation of the temperature field and the low level jet caused by the landfall of typhoon should be paid more attention to in forecasting operations.
文章编号: 中图分类号: 文献标志码:
基金项目:公益性行业(气象)科研专项(GYHY201206010)、中国气象局预报员专项(CMAYBY2013 048)、广东省气象局科技创新团队(201101)和广东省气象局科研基金重点项目(2014A02)共同资助
作者 | 单位 |
程正泉 | 区域数值天气预报重点实验室,广州 510080 广州中心气象台,广州 510080 |
林良勋 | 广州中心气象台,广州 510080 |
沙天阳 | 广州中心气象台,广州 510080 |
杨国杰 | 广州中心气象台,广州 510080 |
引用文本:
程正泉,林良勋,沙天阳,杨国杰,2014.“尤特”特大暴雨过程的热力条件分析[J].气象,40(12):1507-1512.
CHENG Zhengquan,LIN Liangxun,SHA Tianyang,YANG Guojie,2014.Analysis of Atmosphere Stratification in Extremely Heavy Rainfall Event Associated with Severe Typhoon Utor[J].Meteor Mon,40(12):1507-1512.
程正泉,林良勋,沙天阳,杨国杰,2014.“尤特”特大暴雨过程的热力条件分析[J].气象,40(12):1507-1512.
CHENG Zhengquan,LIN Liangxun,SHA Tianyang,YANG Guojie,2014.Analysis of Atmosphere Stratification in Extremely Heavy Rainfall Event Associated with Severe Typhoon Utor[J].Meteor Mon,40(12):1507-1512.