Mass Balance Sensitivity to Climate Change of the Glacier No.1 at the Urumqi River Head, Tianshan Mts.

In this paper the degree-day mass balance model is applied to the sensitivity test of mass balance /ELAto climate change of the Glacier No.1 at the Urumqi river head, Tianshan Mts. Results demonstrate that mass balance of a continental type glacier with warm season accumulation as the Glacier No.1 is less sensitive than that of a maritime type glacier. On the glacier air temperature rise of 1℃ or precipitation increase by 20% can cause the ELAshifting 81 m up or 31 m down. Air temperature and precipitation play different roles in mass balance, i.e. elevation-dependent mass balance follows the temperature variation by means of rotation against the elevation axis and it shifts parallel to precipitation change. Assuming a future temperature rise of 2 ℃ the minus mass balance trend of the glacier can not be reversed even if precipitation increases by 30%.