Developing Conditions, Amounts and Distributions of Glaciers in Gongga Mountains
Su Zhen, Liang Dalan and Hong Ming (Lanzhou Institute of Glaciology and Geocryology, Academia Sinica)
Lying at the southeastern margin of the Tibetan Plateau, the Gongga Mts., with 1 / 6 the whole area above 5 000 m a.s.l. is situated at the middle section of the Daxueshan Mts. where the highest peak is up to 7 514 m a.s.l.. Based on meteorological observation, the precipitation in the accumulation area is estimated to be about 3 000 mm each year and the annual airtemperature is about -4.1--5.1℃ at the equilibrium line on the east slope of the mountains, while the annual precipitation on the west slope is 1 800 mm in the accumulation area. Such an aboundant accumulation and necessarily lower temperature are prefitable to glacier development. There are 74 glaciers with a total area of 255.1 square km around the Gongga Mts. where different glaciers types can be found. Though glaciers are relatively concentrated, the difference in scale is most obvious. Glaciers on east slope are less than those on the west, but glaciers on the east slope are larger than those on the west, Moreover the snow line altitudes and glacier fronts on the east slope extend to lower altitudes than those on the west.