| 我国秋季连阴雨的气候特征及大气环流特征 |
| |
| 引用本文： | 孙照渤,黄艳艳,倪东鸿.我国秋季连阴雨的气候特征及大气环流特征[J].大气科学学报,2016,39(4):480-489. |
| |
| 作者姓名： | 孙照渤 黄艳艳 倪东鸿 |
| |
| 作者单位： | 南京信息工程大学气象灾害教育部重点实验室/气候与环境变化国际合作联合实验室/气象灾害预报预警与评估协同创新中心 |
| |
| 基金项目： | 公益性行业(气象)科研专项(GYHY201306028);国家自然科学基金资助项目(41075070);国家重点基础研究发展计划(973计划)项目(2013CB430202);江苏省自然科学基金资助项目(BK20131431);江苏高校优势学科建设工程资助项目(PAPD) |
| |
| 摘 要： | 采用1961—2010年全国753站逐日降水资料,给出了我国秋季连阴雨的定义,分析我国秋季连阴雨和不同级别(5~7 d、8~10 d和11 d及以上)秋季连阴雨的气候特征;将我国秋季连阴雨划分为华北、西南、江淮和华南地区4区,并分析华北地区秋季连阴雨期间和不同级别秋季连阴雨期间的大气环流特征。结果表明:1)我国秋季连阴雨及不同级别秋季连阴雨50 a累计频次在长江中上游地区较大,黄河以北地区较小;随着连阴雨级别的增加,连阴雨频次大值区由东南地区移向西南地区;频次标准差与频次的分布特征类似。2)华北地区连阴雨及不同级别连阴雨期间,巴尔喀什湖与贝加尔湖间的阻塞高压增强,850 h Pa上增强的偏北和偏南气流交汇于华北地区,500 h Pa上东亚大槽槽后偏北气流引导北方冷空气南下,副热带高压西侧偏南气流引导南方暖空气北上,冷、暖空气在华北地区交汇,易形成连阴雨天气。
|
| 关 键 词： | 秋季连阴雨 气候特征 大气环流 |
| 收稿时间： | 2014/4/13 0:00:00 |
| 修稿时间： | 2014/5/14 0:00:00 |
Climate and circulation characteristics of continuous autumn rain in China |
| |
| SUN Zhaobo,HUANG Yanyan and NI Donghong.Climate and circulation characteristics of continuous autumn rain in China[J].大气科学学报,2016,39(4):480-489. |
| |
| Authors: | SUN Zhaobo HUANG Yanyan and NI Donghong |
| |
| Institution: | SUN Zhaobo;HUANG Yanyan;NI Donghong;Key Laboratory of Meteorological Disaster,Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environment Change(IL-CEC)/Collaborative Innovation Center on the Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) ,Nanjing University of Information Science &Technology; |
| |
| Abstract: | Continuous autumn rain is long in duration,meaning it can easily cause crop mold and other adverse effects relating to daily life and industrial and agricultural production.In order to mitigate such losses caused by continuous autumn rain,it is important to study in depth the climate characteristics of continuous autumn rain and its causes.The present study does this based on the daily rainfall and sunshine data of 753 meteorological stations in China in autumn (September-November) from 1961 to 2010,along with NCEP/NCAR reanalysis data for the period 1948-2010.After defining continuous autumn rain in China,its climate characteristics for different levels (5-7 d,8-10 d,and 11 d and above) are analyzed.Based on a general survey of regions where continuous autumn rain was found to happen often during 1961-2010,China is divided into four regions of continuous autumn rain;namely,North China,Southwest China,the Changjiang-Huaihe basin,and South China,where representative stations are Xingtai (Hebei Province),Wufeng (Hubei Province),Gushi (Henan Province) and Yongan (Fujian Province),respectively.The circulation characteristics of continuous autumn rain and continuous autumn rain of different levels in North China are also analyzed.The results show that: (1)The accumulated frequency of continuous autumn rain and continuous autumn rain of different levels mainly concentrates in the mid-upper reaches of the Yangtze River during 1961-2010,and is very small in the areas north to the Yellow River.With an increase in the level of rain,the high-frequency areas move from southeast to southwest.The frequency standard deviation is similar to the frequency of continuous autumn rain and continuous autumn rain of different levels. (2)During the continuous autumn rain and continuous autumn rain of different levels in North China,in the 500 hPa geopotential height field,the northern cold air is guided to the south by northerly flow after the East Asian trough,and southern warm air is guided to the north by southerly flow on the west side of the subtropical high.The cold and warm air masses meet over North China,which is beneficial to the formation of the continuous rain weather.Positive height anomalies are located over North China,but negative height anomalies are located in the east and west sides of North China. (3)The circulation patterns feature a number of differences among the different levels of continuous autumn rain.The East Asian trough and Urals ridge are the strongest and located farthest east for the 8-10 d level,followed by the 11 d and above level,and finally the 5-7 d level.The trough is most obvious over Lake Balkhash for the 8-10 d level. (4)In the 850-hPa wind field,the enhanced southern and northern air streams meet over North China,as do the anomalous southerlies and northerlies.However,the wind field features differ among the different levels of continuous autumn rain:with an increase in the level of continuous rain,the wind speed converging over North China increases. (5)In the sea level pressure field,the blocking high between Lake Balkhash and Lake Baikal strengthens,and North China is located in the peripheral region of the blocking high.Positive sea level pressure anomalies are located over North China.However,among the different levels of continuous autumn rain,the blocking high strength shows some differences,as does the extent of the enhancement of the blocking high,which is maximum for the 11 d and above level,followed by the 5-7 d level,and is minimum for the 8-10 d level. |
| |
| Keywords: | continuous autumn rain climate characteristics general circulation |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《大气科学学报》浏览原始摘要信息 |
| 点击此处可从《大气科学学报》下载免费的PDF全文 |
|
