Lhasa belongs to the plateau temperate semi-arid monsoon climate zone, with an annual sunshine hours of 3000 hours, which is 1800 hours more than Chengdu in Sichuan Province and 1100 hours more than Shanghai, the largest eastern city in China. It ranks among the top cities in China and is therefore known as the "Sunshine City". Lhasa is located in the north of the the Himalayas. Influenced by the downdraft, it has sunny weather throughout the year with little rainfall, no severe cold in winter, and no intense heat in summer. It belongs to the semi-arid monsoon climate of plateau temperate zone. The highest historical temperature is 29.6 degrees Celsius, the lowest temperature is minus 16.5 degrees Celsius, and the annual average temperature is 7.4 degrees Celsius. The rainfall is concentrated in June, July, August, and September, with an annual sunshine duration of over 3000 hours, earning it the reputation of the "Sunshine City". The annual precipitation is 200-510 millimeters, concentrated from June to September, with frequent nighttime rain, known as the rainy season. The solar radiation is strong, the air is thin, the temperature is low, the temperature difference between day and night is large, and winter and spring are cold, dry, and windy. Annual frost free period of 100-120 days.