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| Titel |
Interannual variability of air-sea CO2 fluxes and carbon system in the East Siberian Sea |
| VerfasserIn |
I. I. Pipko, I. P. Semiletov, S. P. Pugach, I. Wåhlström, L. G. Anderson |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1726-4170
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| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 8, no. 7 ; Nr. 8, no. 7 (2011-07-22), S.1987-2007 |
| Datensatznummer |
250006055
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| Publikation (Nr.) |
 copernicus.org/bg-8-1987-2011.pdf |
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| Zusammenfassung |
Over the past couple of decades it has become apparent
that air-land-sea interactions in the Arctic have a substantial impact on
the composition of the overlying atmosphere (ACIA, 2004). The Arctic Ocean
is small (only ~4 % of the total World Ocean), but it is surrounded
by offshore and onshore permafrost which is thawing at increasing rates
under warming conditions, releasing carbon dioxide (CO2) into the water
and atmosphere. The Arctic Ocean shelf where the most intensive
biogeochemical processes have occurred occupies 1/3 of the ocean. The East
Siberian Sea (ESS) shelf is the shallowest and widest shelf among the Arctic
seas, and the least studied. The objective of this study was to highlight
the importance of different factors that impact the carbon system (CS) as
well as the CO2 flux dynamics in the ESS. CS variables were measured in
the ESS in September 2003 and, 2004 and in late August–September 2008. It
was shown that the western part of the ESS represents a river- and
coastal-erosion-dominated heterotrophic ocean margin that is a source for
atmospheric CO2. The eastern part of the ESS is a
Pacific-water-dominated autotrophic area, which acts as a sink for
atmospheric CO2.
Our results indicate that the year-to-year dynamics of the partial pressure
of CO2 in the surface water as well as the air-sea flux of CO2
varies substantially. In one year the ESS shelf was mainly heterotrophic and
served as a moderate summertime source of CO2 (year 2004). In another
year gross primary production exceeded community respiration in a relatively
large part of the ESS and the ESS shelf was only a weak source of CO2
into the atmosphere (year 2008). It was shown that many factors impact the
CS and CO2 flux dynamics (such as river runoff, coastal erosion,
primary production/respiration, etc.), but they were mainly determined by
the interplay and distribution of water masses that are basically influenced
by the atmospheric circulation. In this contribution the air-sea CO2
fluxes were evaluated in the ESS based on measured CS characteristics, and
summertime fluxes were estimated. It was shown that the total ESS shelf is a
net source of CO2 for the atmosphere in a range of 0.4 × 1012
to 2.3 × 1012 g C. |
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