The Guliya ice core, 309m long, is the longest one among the ice cores from mountain glaciers in middle and low latitudes. Based on the data of δ18O, glacial accumulation rate, major anions and main cations in the Guliya ice core, climatic and environmental changes in the past about 2 000a are studied in this paper.In the northern part of Qnghai-Xizang (Tibet) Plateau, it is found that δ18O and glacial accumulation rate are the reliable indexes of air temperatUre and precipitation respectively. Therefore, t...