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| Titel |
800-year ice-core record of nitrogen deposition in Svalbard linked to ocean productivity and biogenic emissions |
| VerfasserIn |
I. A. Wendl, A. Eichler  , E. Isaksson, T. Martma, M. Schwikowski |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 15, no. 13 ; Nr. 15, no. 13 (2015-07-07), S.7287-7300 |
| Datensatznummer |
250119871
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| Publikation (Nr.) |
 copernicus.org/acp-15-7287-2015.pdf |
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| Zusammenfassung |
| We present the records of the two nitrogen species nitrate (NO3-) and
ammonium (NH4+) analysed in a new ice core from Lomonosovfonna,
Svalbard, in the Eurasian Arctic covering the period 1222–2009. Changes in
melt at the Lomonosovfonna glacier are assumed to have a negligible effect on
the decadal variations of the investigated compounds. Accordingly, we use
decadal records to investigate the major emission sources of NO3- and
NH4+ precursors and find that during the twentieth century both
records are influenced by anthropogenic pollution from Eurasia. In
pre-industrial times NO3- is highly correlated with methane sulfonate
(MSA), which we explain by a fertilising effect. We propose that enhanced
atmospheric NO3- concentrations and the corresponding nitrogen input
to the ocean trigger the growth of dimethyl-sulfide-(DMS)-producing
phytoplankton. Increased DMS production results in elevated fluxes to the
atmosphere where it is oxidised to MSA. Eurasia was presumably the main
source area also of pre-industrial NO3-, but a more exact source
apportionment could not be performed based on our data. This is different for
NH4+, where biogenic ammonia (NH3) emissions from Siberian
boreal forests were identified as the dominant source of pre-industrial
NH4+. |
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