| 2018年汛期我国东部雨季天气特征分析 |
| |
| 引用本文： | 李勇,尹姗,赵晓琳,周宁芳.2018年汛期我国东部雨季天气特征分析[J].新疆气象,2020,14(1):13-20. |
| |
| 作者姓名： | 李勇 尹姗 赵晓琳 周宁芳 |
| |
| 作者单位： | 国家气象中心 北京 100081,国家气象中心 北京 100081,国家气象中心 北京 100081,国家气象中心 北京 100081 |
| |
| 基金项目： | 国家科技支撑计划课题(2015BAC03B07)资助 |
| |
| 摘 要： | 2018年主汛期我国平均降水量为652.0 mm，较常年同期偏少95.0 mm。空间分布上呈现出北方降水偏多，南方降水偏少的总体特征。其中华南地区前汛期降水量较常年偏少5—8成, 江淮地区梅雨季降水量较常年偏少4—8成，华北地区降水量较常年偏多2—8成，局地偏多2倍以上。除华北雨季开始时间较常年偏早外，华南前汛期、江淮梅雨期开始时间均较常年偏晚。2018年主汛期全国平均降水日数71.29d，较常年偏少12.67d。共出现暴雨5229 站日，较常年偏少280站日。华南前汛期降水阶段性明显，中前期冷空气较弱，副高异常偏强是降水偏少的重要原因，后期南海季风爆发，水汽条件明显改善，中高纬度环流经向度增大，降水明显增强；江淮梅雨期间，长江中下游地区高层辐散抽吸的动力条件以及低层水汽辐合均较常年同期偏弱，是梅雨期降雨强度整体偏弱、梅期偏短的重要原因。华北雨季期间，东北亚稳定维持着一个异常反气旋环流，在中纬度地区形成东高西低的环流形势，是华北地区出现强降水的重要原因之一。2018年汛期全国共出现34次区域性暴雨过程，区域性暴雨过程的次数与常年同期基本持平或略偏少，全国暴雨站日也较常年同期略偏少。
|
| 关 键 词： | 雨季 华南前汛期 江淮梅雨 华北雨季 区域性暴雨 |
| 收稿时间： | 2019/7/18 0:00:00 |
| 修稿时间： | 2019/9/6 0:00:00 |
Analysis of the Characteristics of Rainy Season in Eastern China in 2018 |
| |
| Abstract: | In 2018, the average precipitation in China during the main flood season is 652.0mm, which is 95.0mm less than normal. The spatial distribution shows that the precipitation in the north region is more than normal, while the southern region is less than normal. The rainy season in North China started earlier than normal. The start time are all later than normal in the early flood season in South China, the Meiyu period in the middle and lower reaches of the Yangtze River. Weak cold air and strong subtropical high pressure are important reasons for the lack of precipitation in the middle and early stages of the South China during the first flood season. In the late period of the South China period, the South China Sea monsoon erupted, and the low-level water vapor conditions improved significantly. At the same time, the meridional degree of the middle and high latitudes increased, and the precipitation increased significantly. During the Meiyu rainy season, the dynamic conditions of high-level divergence pumping and the low-level water vapor convergence in the middle and lower reaches of the Yangtze River were weaker than normal. The rainfall intensity during the Meiyu period was weak and the Meiyu period was short. During the rainy season in North China, the anomalous anticyclone circulation in Northeast Asia is stable, and the mid-latitude region forms a high circulation in the east and a low circulation in the west, which is conducive to the emergence of strong precipitation in North China. There were 34 regional rainstorms in the whole country during the flood season. |
| |
| Keywords: | rainy season the early flood season in South China Meiyu period North China rainy season regional rainstorm |
|
| 点击此处可从《新疆气象》浏览原始摘要信息 |
| 点击此处可从《新疆气象》下载免费的PDF全文 |
|
