TY  - JOUR
AU  - Beine Harry, Anastasio Cort
PY  - 2011//
TI  - Soluble, light-absorbing species in snow at Barrow, Alaska
JO  - J. Geophys. Res.
SP  - D00R05-
VL  - 116
PB  - AGU
KW  - HULIS
KW  - OASIS
KW  - chromophores
KW  - light absorption
KW  - snow pack
KW  - 0317 Atmospheric Composition and Structure: Chemical kinetic and photochemical properties
KW  - 0322 Atmospheric Composition and Structure: Constituent sources and sinks
KW  - 0365 Atmospheric Composition and Structure: Troposphere: composition and chemistry
KW  - 0736 Cryosphere: Snow (1827
KW  - 1863)
KW  -
N2  - As part of the international multidisciplinary Ocean – Atmosphere – Sea Ice – Snowpack (OASIS) program we analyzed more than 500 terrestrial (melted) snow samples near Barrow, AK between February and April 2009 for light absorption, as well as H2O2 and inorganic anion concentrations. For light absorption in the photochemically active region (300–450 nm) of surface snows, H2O2 and NO3- make minor contributions (combined < 9% typically), while HUmic LIke Substances (HULIS) and unknown chromophores each account for approximately half of the total absorption. We have identified four main sources for our residual chromophores (i.e., species other than H2O2 or NO3-): (1) vegetation and organic debris impact mostly the lowest 20 cm of the snowpack, (2) marine inputs, which are identified by high Cl- and SO42- contents, (3) deposition of diamond dust to surface snow, and (4) gas-phase exchange between the atmosphere and surface snow layers. The snow surfaces, and accompanying chromophore concentrations, are strongly modulated by winds and snowfall at Barrow. However, even with these physical controls on light absorption, we see an overall decline of light absorption in near-surface snow during the 7 weeks of our campaign, likely due to photo-bleaching of chromophores. While HULIS and unknown chromophores dominate light absorption by soluble species in Barrow snow, we know little about the photochemistry of these species, and thus we as a community are probably overlooking many snowpack photochemical reactions.
SN  - 0148-0227
UR  - http://dx.doi.org/10.1029/2011JD016181
N1  - exported from refbase (http://publi.ipev.fr/polar_references/show.php?record=1145), last updated on Wed, 03 Jul 2024 19:48:57 +0200
ID  - BeineHarry2011
ER  -