Recent high-resolution glaciochemical record from a Dasuopu firn core of middle Himalayas

• 来源期刊: 科学通报（英文版）
• 年，卷（期）: 2008,（3）
• 页码范围: 418-425
• 页数: 8页
• 语种: 英文
• DOI: 10.1007/s11434-008-0098-7

摘要

A 16.8 m firn core of middle Himalayas was recovered on the col of Dasuopu glacier in August 2006, being 7000 m above sea level. A total of 317 samples were measured for stable oxygen isotope ratios (δ18O) and major ion concentrations (Na+, NH4+, K+, Mg2+, Ca2+, Cl+, SO42-, and NO3+). The firn core dating and seasonal partitioning were carried out based on the marked seasonal variations along the stable oxygen isotopes and crustal species (Ca2+, Mg2+) profiles. The multi-parameters and high-resolution glaciochemical data set of Dasuopu firn core recorded the detailed chemical characteristics of pre-cipitation in high-elevation region, middle Himalayas, since 1991 A.D., which mainly originated from the crustal and anthropogenic sources, while the sea-salt contribution was minor. The seasonal variability of major ion concentrations was dominated by the seasonal alternation of the prevalent air mass, at-mospheric circulation situation and precipitation regime. Linear regression analysis indicated that most of the variance in annual ionic fluxes can be explained by a linear dependence on snow accumu-lation rate.