Abstract: On the basis of analyses of the importance of cryospheric researches in China and the current status of cryospheric sciences over the world, this paper addresses some key issues and main contents that must be handled at present. Generally, the impacts of cryospheric changes on climate, sea level and physical environments receive worldwide concerns, whereas in China, cryospheric changes are of great importance in ecology, fresh water, physical environments and climate since China has a most developed cryosphere among countries in mid- and low-latitudes. The key issues that should be currently addressed are: i) fluctuation mechanisms of different types of glaciers in responses to climate changes and the scale-conversion in water resources assessments of glaciers; ii) modeling of water and heat exchanges between frozen soil and vegetation; iii) parameterization of physical processes in the cryosphere as well as their coupling with climate models. Towards full solution of these key issues, works in following three aspects should be highlighted, i.e. cyrospheric processes and their responses to climate changes, influences of cryospheric changes, and adaptation strategies for cryospheric changes.

Key words: cryoshpere, climate change, impact, water resources