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| Titel |
Rate of Iceland Sea acidification from time series measurements |
| VerfasserIn |
J. Olafsson, S. R. Olafsdottir, A. Benoit-Cattin, M. Danielsen, T. S. Arnarson, T. Takahashi |
| 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 ; 6, no. 11 ; Nr. 6, no. 11 (2009-11-25), S.2661-2668 |
| Datensatznummer |
250004100
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| Publikation (Nr.) |
 copernicus.org/bg-6-2661-2009.pdf |
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| Zusammenfassung |
| The Iceland Sea is one part of the Nordic Seas. Cold Arctic Water prevails
there and the deep-water is an important source of North Atlantic Deep
Water. We have evaluated time series observations of measured pCO2 and
total CO2 concentration from discrete seawater samples during 1985–2008
for the surface and 1994–2008 for deep-water, and following changes in
response to increasing atmospheric carbon dioxide. The surface pH in winter
decreases at a rate of 0.0024 yr−1, which is 50% faster than average
yearly rates at two subtropical time series stations, BATS and ESTOC. In the
deep-water regime (>1500 m), the rate of pH decline is a quarter of that
observed in surface waters. The surface seawater carbonate saturation states
(Ω) are about 1.5 for aragonite and 2.5 for calcite, about half of
levels found in subtropical surface waters. During 1985–2008, the degree of
saturation (Ω) decreased at an average rate of 0.0072 yr−1 for
aragonite and 0.012 yr−1 for calcite. The aragonite saturation horizon
is currently at 1710 m and shoaling at 4 m yr−1. Based on this rate of
shoaling and on the local hypsography, each year another 800 km2 of
seafloor becomes exposed to waters that have become undersaturated with
respect to aragonite. |
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