Jiangxi continues to issue drought red warning. Why does the southern region continue to suffer from drought after autumn?

Since July, there has been a serious drought in Jiangxi, and Jiangxi has continuously issued a red warning of drought. According to the report of China Meteorological Bureau, the drought in southern China will continue for some time, and there will be no easing trend in a short time. There are two main reasons for the persistent drought in the south after autumn.

I. Impact of the Warm High in the Mainland After July this year, the subtropical high in the western Pacific extended westward, and the southern part of China was affected by this high. At the same time, the Iranian high pressure also extends to China and converges with the continental high pressure in southern China, thus forming a huge continental warm high pressure belt. In the area under the continental cold high pressure belt, there will be long-term high temperature.

In addition, due to the existence of this large-scale warm and high-pressure belt, water vapor can not be transported to the southern part of China, which makes the precipitation much lower than in previous years and makes the southern part of China dry. According to the forecast of the Central Meteorological Observatory, the precipitation has not improved in June of 5438+00, and the drought will not be effectively alleviated.

Second, there are fewer typhoons in summer. Although the typhoon is very destructive, it can also bring a lot of precipitation. The number of typhoons generated this summer is relatively small, only nine, and in previous years, it was generally about a dozen, while there were only three landing typhoons, and in previous years, it was generally about five. The decrease in the number of typhoons has also affected the precipitation in southern China. However, according to the statistical results, there may still be 1-2 typhoons landing in June+10/October in 5438, which will bring some precipitation to southern China.

In a word, the climate this year is quite abnormal, and extreme weather has appeared in many places. According to relevant statistics, the number of dry days in South China has increased by 3 1 day since July compared with the same period of last year. The drought has affected Jiangxi, Fujian, Anhui, Hubei, Hunan and Zhejiang, with the largest impact range of 19 and 6 1 year.