The apparent difference between the thermometer estimated surface warming and the air temperature decreasing in the lower troposphere estimated from satellites and radiosondes in recent years, makes the global warming being as an open question. By comprehensive analyses for the variations of the every component of the cryosphere, such as glacier, snow cover, permafrost and sea ice, etc., together with the records of ice cores from different areas, it was verified that climate was warming over the global surfaces, both in lower and high altitudes, in the 20th century. Moreover, it was pointed out that it is necessary to study the interaction process between the cryosphere and atmosphere/ocean for understanding the Earth climate system.