The weather in Qinghai Lake area is typically mild semi-arid steppe climate. It’s cool in summer and cold in winter, with strong sunshine and less rainfall.
The annual daylight hours are more than 3000 in the lake area, which is 700 hours more than the places east to the same latitude. The annual total quantity of radiation is from 171.64 to 106.693 therm/square centimeter, which is higher than Huabei Plain and Huangtu Plateau.
Every year, the average temperature is from 1.1℃ to 0.3℃ in eastern and southern lake area. In western and northern part, the average temperature is from -0.8℃ to 0.6℃, with the highest from6.7℃-0.8℃ and lowest from -6.7℃-4.9℃. The extreme temperature record is 25℃ and -33.4℃.
In the lake area, the annual rainfall is relatively not enough, which is a litter higher in eastern and southern part (412.8mm and 359.4mm), and in western and northern part the number is 360.4mm and 324.5 mm. However, the evaporation (1502mm/year ) exceeds the rainfall.The amount of rainfall is different in seasons, with largest amount from May to Sep.
4,Wind and sandstorm
In the lake area, the wind is quite strong, especially from Feb and Apr. For example, in Gangcha, there are about 47.3 days with strong winds annually, which is 5.9-9.3 days in Feb and Apr, 19 days in Mar. The sandstorms occur 14 days annually. In Buha River estuary, the highest wind force reaches 9-10 grade. Because of high altitude, the whole area suffers northwestern wind for most time.
The water temperature in lake area is different in seasons. In Aug, the highest is 22.3 ℃ and average is 16℃. In the lower gradient in the lake, the average temperature is 9.5 ℃ and the lowest is 6 ℃. In winter, the surface lake temperature is -0.9℃ and lower gradient temperature is 3.3℃. After the lake gets melting, the temperature gradually rises.
Since the middle of Nov, the lake gets frozen for 108-116 days. The average thickness of ice is 40cm. Until the middle of Mar, the ice begins to split and floats with wind force. The largest bulk of ice is 10 cubic meter. After the middle of Apr, all the ice turns into water.