Gansu has a dry climate with plenty of sunshine, strong radiation and the temperature varies greatly from day to night. The annual average temperature is between 0℃-14℃ dropping from the southeast to the northwest. It is 4℃-9℃ in Hexi Corridor, 0℃-6℃ in Qilian mountainous area, 5℃-9℃ and 7℃-10℃ in Longzhong and Longdong respectively. Its annual rainfall is about 300 millimeters and differs greatly in different parts. It is reduced from 760 millimeters in the southeast to 42 millimeters in the northwest. The seasonal rainfall is also uneven and concentrated mainly from June to September. Gansu has rich solar energy resources with an annual sunshine time of 1,700-3,300 hours, increasing from the southeast to the northwest. Hexi Corridor has a maximum annual sunshine time of 2,800-3,300 hours, Longnan has a minimum sunshine time of 1,800-2,300 hours, Longzhong, Longnan and Gannan has an annual sunshine time of 2,100-2,700 hours.
