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Southeastern Tibet is the type area for monsoonal maritime glaciers in the Qinghai–Tibet Plateau with more than 4000 mountain glaciers covering an area of approximately 8000 km 2 . Based on moraines in the Boduizangbo River Valley, glacial advances have been recognized for the Guxiang, Baiyu, and Yuren Glaciations. Cosmogenic radionuclide surface exposure, ESR, and radiocarbon dating methods are used to estimate moraine ages. The dates suggest that glacial advances occurred during MIS-6, MIS-2 and MIS-1. Moraines of possible MIS-4 or MIS-3 age are also present, but have not yet been dated. During the Guxiang Glaciation, glaciers converged in the Boduizangbo Valley and formed a glacier approximately 100 km long, reaching the Parlongzangbo River Valley. During the Baiyu Glaciation the glacier was about 80 km long, yet did not reach the main valley of the Parlongzangbo River. During the Yuren Glaciation, glaciers advanced only within tributary valleys feeding the Boduizangbo River. Based on glacier extent, reconstructed equilibrium line altitudes during the Guxiang and Baiyu Glaciations were approximately 800 m and 600 m lower, respectively than at present. Mean annual air temperatures were depressed by approximately 6.6–7.8 � C compared to present values, estimating a 40% decrease in precipitation during

Guxiang and Baiyu Glaciations are two previously recognized local glaciations of the Tibetan Plateau. They have been widely used as the reference standard for classifying Late Quaternary glaciations on the Tibetan Plateau and its surrounding mountains. However, the numerical chronologies of both glaciations have been lacking. In this study, cosmogenic 10Be dating was undertaken to define the timing of these two glaciations. The surface boulders deposited by the glaciers of the Guxiang and Baiyu Glaciations have exposure ages of 112.9±16.7–136.5±15.8 ka BP and 11.1±1.9–18.5±2.2 ka BP, respectively. It is likely that the Guxiang and Baiyu Glaciations correspond to marine isotope stages 6 and 2, respectively.

Cosmogenic radionuclide (CRN) exposure ages provide evidence for the limited extent of last glacial maximum glaciers in the Tanggula Shan, central Tibetan Plateau. The most extensive advances occurred during or before marine oxygen isotope stage 6 (MIS-6) based on previous CRN exposure ages. The second most extensive advance occurred during or before MIS-4 based on previous ages and new ages of 41,400 ± 4300, and 66,800 ± 7100 10Be yr. A MIS-2 advance of less than 3 km occurred between 31,900 ± 3400 and 16,000 ± 1700 10Be yr.

According to the regional climatic model and tendency, the long-term climatic change, which presents not only the climatic change, but also the regional climatic change, is discussed. The glacial scale is a very important climatic indicator, which is sensitive to temperature and precipitation, and provides a foundation for the comparison of the modern and various glaciers in Bodui district. The declination value of ELA and the relevant climatic change are estimated. The results of 3 glaciers on Boduizangbo show that both modern ELA and former ELAs decrease from south to north, due to the northwards monsoon and the declining precipitation. The value of ELA in LGM is about 300-600m. If the precipitation remains constant, the summer average temperature in LGM declines by 3.7-6 K.

The spatial distribution and change of the mountain glaciers in midlatitude areas are quite sensitive to climatic response. According to the well-preserved old glacial relics formed during the LGM in the southeast Nyanqintanggula Mountain on the Tibetan Plateau and the relationship between the glacier variety and the climate under the modern conditions, this paper suggests that the coupling mechanisms of glaciers and climatic factors in the regional climatic fluctuation are mainly influenced by the Indian Monsoon, and a response model of the relationship between the glaciers and the climatic factors through the statistics methods. The result shows that the summer temperature during LGM in this region is 5degC lower than the modern temperature, and the precipitation near the snow line is 66% of the modern precipitation