Carbonaceous particles in Muztagh Ata ice core,West Kunlun Mountains,China

Carbonaceous particles concentrations of OC and EC are determined using a two-step gas chromatography system in Muztagh Ata ice core covering the time period of 1955–2000. Over the period represented by the core, OC and EC concentrations appear to have changed significantly, varied in the range of 17.7–216.7 and 6.5–124.6, and averaged 61.8, 32.9 ng·g⁻¹, respectively. The average concentration of EC in Muztagh Ata ice core is much lower than that in an Alpine ice core record (100–300 ng·g⁻¹) during the same period, but it is a factor of 14 in Greenland ice core (2.3 ng·g⁻¹), this may induce a strong impact on the snow albedo in the last 46 years in our study area. Observations indicate two periods with obviously high deposition concentrations (1955–1965 and 1974–1989) and two periods with low concentrations (1966–1973 and 1990–1995), as well as a recent increasing trend. By comparing EC and SO₄²⁻ concentration variations and deciphering OC/EC ratios recorded in the same ice core, we can judge roughly that the carbonaceous particles deposited in Muztagh Ata ice core were attributed to fossil fuel combustion sources. Supported by the National Natural Science Foundation of China (Grant Nos. 40471022 and 40525001), the Ministry of Science and Technology of China (Grant No. 2005CB422004), and the Innovation and Centurial Program of Chinese Academy of Sciences (Grant No. 2004401)