Evaluation of glacier runoff in Tailan basin by monthly degree-day model

This study analyzes long-term climate and glacier runoff changes to examine climate change and glacier mass balance response over the past 47 years by applied a modified monthly degree-day models in Tailan basin, the Tianshan Mountains of China. The results show that the snow line altitude is much closed to that of observation or other´s result, which suggested the model, is valid to evaluate the glacier runoff changes. The mass balance of Tailan glaciers is all below zero after 1982-1983, the total mass balance is -16.07m during 1961-2007. The average discharge of glacier during 2001-2007 has increased 25% than that between 1961 to 1990, about 2% contributed from the increased of precipitation, and another 23% contributed from the lost of glacier mass balance. The 0.4 degree increase of summer air temperature has made -235.7mm yearly mass balance compensate with 18.3mm increase of annual precipitation, which equal to -635mm per degree mass balance without increase of precipitation. The result reveals that the contribution of glacier runoff to Tailan hydrological station has remarkable increase after 1990, especially after 2000.