• CN 62-1175/P
• ISSN 1006-7639

Journal of Arid Meteorology ›› 2022, Vol. 40 ›› Issue (5): 748-763.

• Research on Severe Drought in the Yangtze River Basin in 2022 •

Characteristics of high temperature, drought and circulation situation in summer 2022 in China

1. 1. Lanzhou Regional Climate Center， Lanzhou 730020， China
2. Jiuquan Meteorological Bureau of Gansu Province， Jiuquan 735000， Gansu， China

2022年夏季我国高温干旱特征及其环流形势分析

1. 1.兰州区域气候中心，甘肃 兰州 730020
2.甘肃省酒泉市气象局，甘肃 酒泉 735000
• 作者简介:林纾（1964—），女，福建福州人，正研级高级工程师，主要从事短期气候预测和气候变化研究. E-mail:treewest@163.com
• 基金资助:
国家重点研发计划项目(2018YFC1505601);甘肃省气象局面上项目(Ms2022-18)

Abstract:

In the summer of 2022, there was a climate anomaly with the highest average temperature and less precipitation since 1961 in China, accompanied by the strongest nationwide high temperature processes (except northeastern China) and a wide range and strong summer drought in the middle and lower reaches of the Yangtze River and Sichuan and Chongqing. For the persistence and extremity of the high temperature and drought event in this summer in China, this paper analyzes the temporal and spatial distribution characteristics and cirulation situation based on the daily maximum temperature and precipitation of 2162 meteorological stations in China from June to August 2022 and the daily reanalysis data of NCEP (National Centers for Environmental Prediction) /NCAR (National Center for Atmospheric Research), which will be of some references for the forecast of summer high temperature and drought with different time scales in southern China. The results show that in the summer of 2022, a total of 48 198 high temperature events occurred in 76.0% of the stations in China, among which 36.6% of the stations experienced 3001 extreme high temperature events. The stations with more than 20 extreme high temperature events all distributed in the Sichuan Basin, and the high temperature situation was more severe this year than the typical high temperature years since the 21st century. The nationwide high temperature process lasted from June 13 to August 30, a total of 79 days, and the strongest high temperature period was from August 11 to 24. According to the comprehensive ranking of high temperature station numbers, duration, intensity and impact range from strong to weak, the order is East China, Central China, southwestern China, northwestern China, North China and South China, among which, the extreme was the most in southwestern China, while there was no high temperature in northeastern China. The spatial and temporal distribution of drought is basically similar to that of high temperature, and the strongest drought period in China was in mid-August. In the summer of 2022, the 500 hPa over the middle and high latitudes of Eurasia showed a “two ridges and one trough” pattern, especially in July and August, the high pressures ridge near the Ural Mountains and the Sea of Okhotsk formed periodic blocking high. The strong subtropical system blocked the active cold air between the two high pressures to the north of 50°N most of the time, resulting in the pattern of “flood in the north and drought in the south” in China. The Iran high at low latitude extended abnormally to the east, and the western Pacific subtropical high was slightly northward and abnormally extended to the west. The air flow in the control area of the high pressure zone formed by the long-term connection of the two high pressures diverged and sank, which continuously blocked the transport of water vapor to the middle latitude, and was not conducive to the precipitation in the Yangtze River basin. At the same time, the south Asia high at high-level was abnormally eastward and moved to the opposite direction of western Pacific subtropical high at mid-level, which superimposed over the range of 80°E-120°E in the middle and late August, resulting in a stable barotropic structure of the high pressure system controlling a wide range of China, and the center was located over Sichuan and Chongqing region, which made Sichuan-Chongqing region become the large value center of high temperature days and the extreme high temperature event times.

CLC Number: