What caused the drought this year?

First, precipitation continues to be less; Second, the temperature continues to be high; Third, windy weather is frequent; Fourth, precipitation in some areas has been low year after year.

First, the precipitation continues to be less. Precipitation is the basic source of water resources. 1999 In the second half of the year, there was a continuous lack of rain in most areas north of the Yangtze River in China (the regional average of 60% to 70% of the annual precipitation in summer was the lowest in the same period in recent 50 years), and a large area of drought occurred in summer and autumn, resulting in less water storage in water conservancy projects and poor farmland.

Second, the temperature continues to be high. Under the background of global warming, the temperature in most parts of China has been on the high side since February this year. The average temperature in most areas north of the Yangtze River from February to July is 65438 0℃ to 2℃ higher than normal. Especially since May, extreme high temperature weather has occurred several times in most parts of eastern and northwestern China at105 E. The highest temperature is generally 35℃~ 39℃, and in some areas it is 40℃~ 42℃, with Turpan in Xinjiang reaching 47.7℃ on July 17 and Chengde in Hebei and Chaoyang in Liaoning at July/kloc-. The number of days ≥35℃ in eastern North China, north-central and western Inner Mongolia, southwestern Shanxi, western Liaoning, central Shaanxi, parts of Xinjiang, middle and lower reaches of the Yangtze River, most of southern China, Chongqing and other places is greater than 10 days, and some areas are greater than 20 days. Due to the high temperature, the farmland water evaporates quickly, the soil moisture drops sharply, and the drought intensifies.

Third, windy weather is frequent. Due to the frequent activities of cold air and extratropical cyclones in northern China in spring, there are obviously more windy and dusty weather, which also accelerates the evaporation of soil moisture and makes the spring drought in northern China develop rapidly.

Fourth, some areas have less precipitation in successive years. In some areas of Shanxi, Hebei, Tianjin, Inner Mongolia, Shandong, Henan, Shaanxi and Hubei provinces and cities, there has been less precipitation for more than three consecutive years since 1997, resulting in a sharp drop in incoming water, a serious shortage of water storage in water conservancy projects, a decrease in water sources and an increasingly serious drought.