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| Titel |
First glance on simulated fresh water releases around Greenland's coast and its impacts on the ocean circulation |
| VerfasserIn |
Christian Rodehacke, Steffen Olsen, Gao Yongqi, Didier Swingedouw, Matthew Menary, Erik Behrens, Arne Biastoch, Uwe Mikolajewicz |
| Konferenz |
EGU General Assembly 2011
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250054537
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| Zusammenfassung |
| In a warming world increased ocean ice sheet interaction and enhanced surface melting will
led to an additional fresh water flux from Greenland into the surrounding coastal
ocean. To identify robust features of the ocean’s response, a prescribed fresh water
flux of 0.1Â Sv along the greenlandic coast has been simulated in both ocean-only
(NEMO/DRAKKAR, NEMO-DMI) and coupled climate models (IPSL-CM5, HadCM3,
BCM, ECHAM6/MPI-OM). Our preliminary analysis highlights the spreading paths of the
additional fresh water: In most models the fresh water anomaly flows predominately into the
Labrador Sea and heads afterwards into the subpolar Atlantic. There the signal splits
into two branches. One takes a route towards the equator and the other one flows
into the Greenland-Island-Norwegian (GIN) Sea. A common feature is a distinct
warming of the SST after four decades in the northern GIN Sea. A quantitative analysis
shows for most models a decrease of the overflow water mass densities after several
decades. Also volume, that is enclosed by the deep reaching convection during
winter, decreases for the key deep water production sites, namely Labrador Sea
and the GIN Sea. However in some models is the amplitude of the latter signal as
large as the underlying variability. The reduced overflow densities and ventilated
volumes explain the meridional overturning circulation (MOC) reduction at 36°N. The
reduction ranges typically from 0.5 to 5Â Sv and is independent of the absolute
MOC strength in the undisturbed case. Further analysis are required to assess the
different model results and to obtain a more consistent picture of the uncertainties. |
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