Record |
Author |
France J L, Reay H J, King M D, Voisin D, Jacobi H W, Domine F, Beine H, Anastasio C, MacArthur A, Lee-Taylor J, |
Title |
Hydroxyl radical and NOx production rates, black carbon concentrations and light-absorbing impurities in snow from field measurements of light penetration and nadir reflectivity of onshore and offshore coastal Alaskan snow |
Type |
Journal Article |
Year |
2012 |
Publication |
J. Geophys. Res. |
Abbreviated Journal |
|
Volume |
117 |
Issue |
|
Pages |
D00R12 ST - |
Keywords |
Barrow OH black carbon e-folding depth nitrate photochemistry 0736 Cryosphere: Snow (1827, 1863) 0770 Cryosphere: Properties 0798 Cryosphere: Modeling (1952, 4316), |
Abstract |
Photolytic production rates of NO, NO2 and OH radicals in snow and the total absorption spectrum due to impurities in snowpack have been calculated for the Ocean-Atmosphere-Sea-Ice-Snowpack (OASIS) campaign during Spring 2009 at Barrow, Alaska. The photolytic production rate and snowpack absorption cross-sections were calculated from measurements of snowpack stratigraphy, light penetration depths (e-folding depths), nadir reflectivity (350–700 nm) and UV broadband atmospheric radiation. Maximum NOx fluxes calculated during the campaign owing to combined nitrate and nitrite photolysis were calculated as 72 nmol m-2 h-1 for the inland snowpack and 44 nmol m-2 h-1 for the snow on sea-ice and snowpack around the Barrow Arctic Research Center (BARC). Depth-integrated photochemical production rates of OH radicals were calculated giving maximum OH depth-integrated production rates of ~160 nmol m-2 h-1 for the inland snowpack and ~110–120 nmol m-2 h-1 for the snow around BARC and snow on sea-ice. Light penetration (e-folding) depths at a wavelength of 400 nm measured for snowpack in the vicinity of Barrow and snow on sea-ice are ~9 cm and 14 cm for snow 15 km inland. Fitting scaled HULIS (HUmic-LIke Substances) and black carbon absorption cross-sections to the determined snow impurity absorption cross-sections show a “humic-like” component to snowpack absorption, with typical concentrations of 1.2–1.5 μgC g-1. Estimates of black carbon concentrations for the four snowpacks are ~40 to 70 ng g-1 for the terrestrial Arctic snowpacks and ~90 ng g-1 for snow on sea-ice. |
Programme |
1017 |
Campaign |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0148-0227 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
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Approved |
yes |
Call Number |
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Serial |
1698 |
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