Isotopic view on nitrate loss in Antarctic surface snow ...
Massive post-depositional processes alter the nitrate concentration in polar firn where the annual snow accumulation is low. This hinders a direct atmospheric interpretation of the ice core nitrate record. Fractionation of nitrate isotopes during post-depositional nitrate loss may allow estimating t...
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American Geophysical Union
2005
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ftdatacite:10.48350/158455 2024-09-30T14:23:51+00:00 Isotopic view on nitrate loss in Antarctic surface snow ... Blunier, Thomas Floch, Grégoire L. Jacobi, Hans-Werner Quansah, Emmanuel 2005 https://dx.doi.org/10.48350/158455 https://boris.unibe.ch/158455/ unknown American Geophysical Union open access publisher holds copyright http://purl.org/coar/access_right/c_abf2 530 Physics Text ScholarlyArticle article-journal journal article 2005 ftdatacite https://doi.org/10.48350/158455 2024-09-02T10:17:31Z Massive post-depositional processes alter the nitrate concentration in polar firn where the annual snow accumulation is low. This hinders a direct atmospheric interpretation of the ice core nitrate record. Fractionation of nitrate isotopes during post-depositional nitrate loss may allow estimating the amount of nitrate loss in the past. We measured δ15N of nitrate in two Antarctic surface cores from the Dome C area. In concert with the known concentration decrease with depth we observe an increase in the isotopic signature. Assuming a Rayleigh type process we find an isotope effect of ɛ = −54‰. We measured the fractionation factor for photolysis in the laboratory and obtained ɛ = −11.7 ± 1.4‰. As the observed fractionation factor in the firn is much lower this rules out that photolysis in the surface snow is the main process leading to the dramatic nitrate loss in the top centimeters of the firn. ... Text Antarc* Antarctic ice core DataCite Antarctic |
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530 Physics |
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530 Physics Blunier, Thomas Floch, Grégoire L. Jacobi, Hans-Werner Quansah, Emmanuel Isotopic view on nitrate loss in Antarctic surface snow ... |
topic_facet |
530 Physics |
description |
Massive post-depositional processes alter the nitrate concentration in polar firn where the annual snow accumulation is low. This hinders a direct atmospheric interpretation of the ice core nitrate record. Fractionation of nitrate isotopes during post-depositional nitrate loss may allow estimating the amount of nitrate loss in the past. We measured δ15N of nitrate in two Antarctic surface cores from the Dome C area. In concert with the known concentration decrease with depth we observe an increase in the isotopic signature. Assuming a Rayleigh type process we find an isotope effect of ɛ = −54‰. We measured the fractionation factor for photolysis in the laboratory and obtained ɛ = −11.7 ± 1.4‰. As the observed fractionation factor in the firn is much lower this rules out that photolysis in the surface snow is the main process leading to the dramatic nitrate loss in the top centimeters of the firn. ... |
format |
Text |
author |
Blunier, Thomas Floch, Grégoire L. Jacobi, Hans-Werner Quansah, Emmanuel |
author_facet |
Blunier, Thomas Floch, Grégoire L. Jacobi, Hans-Werner Quansah, Emmanuel |
author_sort |
Blunier, Thomas |
title |
Isotopic view on nitrate loss in Antarctic surface snow ... |
title_short |
Isotopic view on nitrate loss in Antarctic surface snow ... |
title_full |
Isotopic view on nitrate loss in Antarctic surface snow ... |
title_fullStr |
Isotopic view on nitrate loss in Antarctic surface snow ... |
title_full_unstemmed |
Isotopic view on nitrate loss in Antarctic surface snow ... |
title_sort |
isotopic view on nitrate loss in antarctic surface snow ... |
publisher |
American Geophysical Union |
publishDate |
2005 |
url |
https://dx.doi.org/10.48350/158455 https://boris.unibe.ch/158455/ |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic ice core |
genre_facet |
Antarc* Antarctic ice core |
op_rights |
open access publisher holds copyright http://purl.org/coar/access_right/c_abf2 |
op_doi |
https://doi.org/10.48350/158455 |
_version_ |
1811638762639196160 |