The cryosphere means the cold region in the earth where solid water such as snow and ice exists. Less than 3% of earth's water is equivalent fresh water, and 80% of them are snow and ice. Their shape is an accumulation of snow, glaciers, ice sheets and permafrost. There are large areas of permafrost in the Eurasian cryosphere, glaciers at high latitude or high mountains. We consider that this area shows an index of climate system because of the remarkable rise of air temperature in the cryosphere. We research climate system, especially Siberia and Mongolia as a cold region. Ice and snow, function as a part of climate system, affect worldwide hydrological cycle and sea level. The melted glacier water in the Eurasia is important water resource of Asian arid regions, further the change in glacier volume influence all living things in the basin.
The discharge from the Arctic large drainage in Eurasia, are showing a rising trend from the last century. Furthermore, the summer arctic sea ice decreases every year. The minimum volume recorded in 2010, the second in 2007, the third in 2008 (as of Oct. 20, 2010). The rapid reduction of arctic sea ice has an impact on precipitation system of Eurasian cryosphere. The correlation between precipitation amount and permafrost temperature gradually turned out.

In this way, snow and ice work as a carrier of energy between ocean, atmosphere and land. It is not clear yet about the causes of increasing discharge and the changing process of snow and ice. To understand the long-term change of hydrological cycle in cryosphere is very useful for our grasp of climate change and global environmental change.
We proceed to observe meteorological elements by ourselves in Eurasian cryosphere, and to carry out a joint research project with research institute in Russia, Mongolia and so on.