Recent studies have shown that cryospheric melting is becoming the dominant factor responsible for sea level rise,and that the melt-water from mountain glaciers and ice caps has comprised the majority of the cryospheric contribution since 2003.Analysis of the estimations of cryospheric melt-water and precipitation in glacier regions indicated that the potential contribution of the cryosphere in China is 0.14 to 0.16 mm a–1,of which approximately 0.12 mm a–1 is from glaciers.The contribution of glaciers in the outflow river basins is about 0.07 mm a–1,accounting for 6.4%of the total from global glaciers and ice caps.
In June 2006, samples were collected from a 90 cm snow-pit at an elevation of 5 040 m a.s.l, in the northern branch firn basin of the Glacier No. 12, Laohugou Valley, in the western part of Qilian Mountain, China. Oxygen isotopes （6180） and major soluble ions were measured. Results showed that Ca2＋ is the dominant cation, and SO42 is the dominant anion. All major ions have close positive correlations with eachother except NO3 and NH4＋. 6180 show positive correlation with air temperature. The method of correlation analysis, sea-salt ion tracer and trend analysis were used to determine the source of the chemical components. The correlation analysis and HYSPLIT backward trajectory analysis suggest that atmospheric soluble dust species dominate the chemical signature.
Xiaoqing CuiJiawen RenXiang QinWeijun SunGuangming YuZebin WangWeigang Liu
