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中国是世界第三大冻土国,有75%的国土面积呈冬冻夏融的周期变化。多年冻土主要分布在青藏高原,东北大、小兴安岭和西部高山。而在青藏高原,较高的海拔高度和严酷的气候条件发育出世界上中低纬度区海拔最高、面积最大的多年冻土,总面积约140万平方公里,占我国多年冻土总面积的65%。在垂直方向上,总的规律是海拔越高,冻土层的厚度越大。
China is the third largest frozen country in the world with 75% of its land area varying in a cycle of winter freezing and summer melting. Permafrost are mainly distributed in the Qinghai-Tibet Plateau, Northeast China, the Little Xing’an Mountains and western mountains. In the Qinghai-Tibet Plateau, high altitude and harsh climatic conditions have developed the highest elevation and the largest area of permafrost in the world, with a total area of about 1.4 million square kilometers, accounting for 65% of the total area of permafrost in China %. In the vertical direction, the general rule is that the higher the altitude, the greater the thickness of the permafrost.