文章摘要
1949-2019年影响山东的热带气旋时空变化、极端降水及异常环流分析*
Analysis of spatio-temporal variation, extreme precipitation and general circulation anomaly of tropical cyclones affecting Shandong province from 1949 to 2019
投稿时间:2021-08-02  修订日期:2021-08-05
DOI:
中文关键词: 热带气旋  山东  极端降水  大气环流  PJ波列  季风槽
英文关键词: tropical cyclones  Shandong province  extreme precipitation  general circulation  PJ wave train  monsoon trough
基金项目:山东省自然科学基金重大基础研究项目(ZR2019ZD12)和国家自然科学基金项目(41975061, 42075024)
作者单位邮编
欧阳婧怡 中国海洋大学物理海洋教育部重点实验室和海洋高等研究院 266100
黄菲 中国海洋大学物理海洋教育部重点实验室和海洋高等研究院 266100
许士斌 中国海洋大学物理海洋教育部重点实验室和海洋高等研究院 266100
曹倩 中国海洋大学物理海洋教育部重点实验室和海洋高等研究院 266100
摘要点击次数: 455
全文下载次数: 0
中文摘要:
   山东位于我国东部沿海,容易受热带气旋(Tropical Cyclone, TC)的影响。本文使用了中国气象局热带气旋资料中心的CMA最佳路径数据集、NCEP/NCAR的再分析资料,对北上影响山东的TC及其造成的极端降水进行统计分析,并揭示了有利于TC北移影响山东的大气环流特征。结果表明:影响山东的TC主要出现于6-9月,其中盛夏时节(7、8月)TC对山东影响最大。TC影响山东时,强度主要为台风及以下等级,或已发生变性。TC会引发山东极端降水事件,TC极端降水多出现在夏秋季(7-9月),其中8月的占比最大,9月次之,TC降水在极端降水事件中的占比约为10%,但年际变化大,有些年占比达60%以上,特别是1990年以来TC对极端降水的贡献显著增强。影响山东的TC主要生成于西北太平洋,多为转向型路径。当环流背景场呈太平洋-日本遥相关型(PJ)的正位相时,TC更易北上影响山东。此时西北太平洋副热带高压位置偏北,在其外围气流的引导下,TC多呈转向型路径影响华东地区。南海和西北太平洋存在有异常气旋式环流,对流活跃,夏季风环流和季风槽加强,有利于TC的生成和发展。同时,华东华南上空有异常上升运动,涡度增大,垂直风切变减小,水汽充沛,TC登陆后强度能得到较好的维持。
英文摘要:
   Shandong is located on the eastern coast of China and is easily affected by tropical cyclones (TC). This article uses the CMA best path data set of the Tropical Cyclone Data Center of China Meteorological Administration and the monthly reanalysis data of NCEP/NCAR to count the TC that affects Shandong. Analyzing its temporal and spatial distribution characteristics and initially reveals the circulation situation field that is beneficial to the northward movement of TC and affects the mid-latitude region. The results showed that most of the TCs affecting Shandong appeared in June-September, and TC had the most significant impact on Shandong during the midsummer season (July and August). When TC affects Shandong, the intensity is mainly at or below the typhoon. TC has an important influence on summer precipitation in Shandong, and it often triggers extreme precipitation events. TC extreme precipitation mainly occurs in summer and autumn (July-September), of which August accounts for the largest proportion, followed by September. The proportion of TC precipitation in extreme precipitation events is about 10%, but the interannual variation is large, with some annual proportions reaching more than 60%. Especially since 1990, the contribution of TC to extreme precipitation increases significantly. Almost all TCs affecting Shandong generate in the Northwest Pacific, and most of them are turning paths. When the circulation background field is in the positive phase of the Pacific-Japan teleconnection type (PJ), TC is more likely to move northward and affect Shandong. At this time, the subtropical high in the Northwest Pacific is northerly. Under the guidance of its peripheral airflow, TC mainly affects East China in a reversing path. There are abnormal cyclonic circulations in the South China Sea and the Northwest Pacific, with active convection and strengthening of the monsoon trough, which is conducive to the generation and development of TC. At the same time, there was an abnormal ascending movement over East China and South China, with increased vorticity, reduced vertical wind shear, and brought abundant water vapor, which enabled the TC to maintain its strength after landing.
View Fulltext   查看/发表评论  下载PDF阅读器
关闭