TY - JOUR AU - Voisin Didier, Jaffrezo Jean-Luc PY - 2012// TI - Carbonaceous species and humic like substances (HULIS) in Arctic snowpack during OASIS field campaign in Barrow JO - J. Geophys. Res. SP - D00R19- VL - 117 PB - AGU KW - HULIS KW - OASIS KW - carbonaceous species KW - snow chemistry KW - snow metamorphism KW - 0305 Atmospheric Composition and Structure: Aerosols and particles (0345 KW - 4801 KW - 4906) KW - 0706 Cryosphere: Active layer KW - 0736 Cryosphere: Snow (1827 KW - 1863) KW - N2 - Snowpacks contain many carbonaceous species that can potentially impact on snow albedo and arctic atmospheric chemistry. During the OASIS field campaign, in March and April 2009, Elemental Carbon (EC), Water insoluble Organic Carbon (WinOC) and Dissolved Organic Carbon (DOC) were investigated in various types of snow: precipitating snows, remobilized snows, wind slabs and depth hoars. EC was found to represent less than 5% of the Total Carbon Content (TCC = EC + WinOC + DOC), whereas WinOC was found to represent an unusual 28 to 42% of TCC. Snow type was used to infer physical processes influencing the evolution of different fractions of DOC. DOC is highest in soil influenced indurated depth hoar layers due to specific wind related formation mechanisms in the early season. Apart from this specific snow type, DOC is found to decrease from precipitating snow to remobilized snow to regular depth hoar. This decrease is interpreted as due to cleaving photochemistry and physical equilibration of the most volatile fraction of DOC. Depending on the relative proportions of diamond dust and fresh snow in the deposition of the seasonal snowpack, we estimate that 31 to 76% of DOC deposited to the snowpack is reemitted back to the boundary layer. Under the assumption that this reemission is purely photochemical, we estimate an average flux of VOC out of the snowpack of 20 to 170 μgC m-2 h-1. Humic like substances (HULIS), short chain diacids and aldehydes are quantified, and showed to represent altogether a modest (<20%) proportion of DOC, and less than 10% of DOC + WinOC. HULIS optical properties are measured and could be consistent with aged biomass burning or a possible marine source. SN - 0148-0227 UR - http://dx.doi.org/10.1029/2011JD016612 N1 - exported from refbase (http://publi.ipev.fr/polar_references/show.php?record=841), last updated on Wed, 03 Jul 2024 11:47:39 +0200 ID - VoisinDidier2012 ER -