Peculiar phenomena regarding climatic and glacial variations on the Tibetan Plateau

In contrast to the worldwide intensive warming and consequent glacier shrinkage during the last 30 years, two peculiar phenomena have been observed on the Tibetan Plateau: (1) the temperature has decreased about 0.68C on the northern Tibetan Plateau, with smaller than average glacier retreat and meltwater discharge, and (2) a number of glaciers have been advancing on the southeast Tibetan Plateau in response to increased precipitation. These observations indicate the complex nature of the response of glaciers to climate changes. The main part of the northern Tibetan Plateau includes the western and central Kunlun Shan and the northern Qiangtang Plateau (roughly 32-378 N, 75-958 E; Fig. 1). The Kunlun Shan are known as the backbone of Asia, extending from west to east, with wide mountain ranges mostly higher than 6000 m a.s.l. and the highest peak at 7167 m a.s.l. The high and broad mountains and prevailing climate provide favorable conditions for glacier develop- ment at present. According to the China Glacier Inventory (CGI), glaciers in the western and central Kunlun Shan cover 12 136 km 2 , and the equilibrium-line altitude (ELA) ranges between 480 and 6200 m. There are several isolated mountains in the northern Qiangtang Plateau with eroded surfaces above 6000 m a.s.l., and some isolated interior lake basins. In this region, glaciers cover an area of about 1500 km 2 , with the ELA ranging from 5300 to 6100 m.