Dunhuang is located in the inner land and separated by high mountains far from the humid maritime climate. So it is under control of the dry continental climate. The first characteristic of its climate is the amplitude of sunshine. The average sunshine hours per year can reach to 3,200 hours. It has 150 frost-free days every year, and the average temperature of the year is 9.3 degrees centigrade with 24.7 degrees centigrade in July and 9.3 degrees centigrade below zero in January. The second feature is the aridity and the lack of rainfall. A north-inclined sinking air current constantly surrounds the Dunhuang region. Therefore, this region has always been dry and lack of rainfall with clear days all through the year. The rainfall of each year is only 39.9 millimeters while the evaporation can reach 2,400 millimeters. The third feature is the distinction of four seasons with long winter and short summer as well as the great difference in temperature between day and night. It is just as the saying goes: "to wear a fur-lined jacket in the morning, a yarn-made clothes at noon; to eat the water melon near a stove".