Light-absorbing snow impurity concentrations measured on Northwest Greenland ice sheet in 2011 and 2012

• DOI: 10.5331/bgr.32.21
• Publication Date: 2014-08-12T23:09:06Z
• Authors: Teruo AOKI; Sumito MATOBA; Satoru YAMAGUCHI; Tomonori TANIKAWA; Masashi NIWANO; Katsuyuki KUCHIKI; Kouji ADACHI; Jun UETAKE; Hideaki MOTOYAMA; Masahiro HORI
• Keywords: Greenland ice sheet; Ice core; Mineral dust; Sublimation

Light-absorbing snow impurities of elemental carbon (EC), organic (OC), and mineral dust have been measured at three locations elevations from 1,469 to 1,992 m on August 1, 2011, the site SIGMA-A (78°N, 68°W, elevation 1,490 m) northwest Greenland ice sheet (GrIS) during period June 28 July 12, 2012. At SIGMA-A, a remarkable surface lowering together with melting was observed observation in 2012, when record event occurred over GrIS. The concentrations were 0.9, 3.8, 107 ppbw for EC, OC, dust, respectively, beginning period, which increased 4.9, 17.2, 1327 end. EC remarkably higher than those 2011 recent measurements Summit. However, our OC could be underestimated because study indicates that collection efficiency quartz fiber filter, we employed, is low. We confirm impurity enhanced can explained by effects sublimation/evaporation melt amplification associated drastic melting. Scanning electron microscopy analysis 12 revealed major component size larger 5 μm, suggests possible emission source areas are peripheral bare soil regions and/or Canadian Arctic.