AMOC recovery in a multi-centennial scenario using a coupled atmosphere-ocean-ice sheet model

We simulate the two Coupled Model Intercomparison Project scenarios RCP4.5 and RCP8.5, to assess the effects of melt‐induced fresh water on the Atlantic meridional overturning circulation (AMOC). We use a newly developed climate model with high resolution at the coasts, resolving the complex ocean d...

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Bibliographic Details
Published in:Geophysical Research Letters
Main Authors: Ackermann, Lars, Danek, Christopher, Gierz, Paul, Lohmann, Gerrit
Format: Article in Journal/Newspaper
Language:unknown
Published: Wiley 2020
Subjects:
Online Access:https://epic.awi.de/id/eprint/52899/
https://epic.awi.de/id/eprint/52899/1/2019GL086810.pdf
https://epic.awi.de/id/eprint/52899/2/grl61025-sup-0001-text_si-s01.pdf
https://hdl.handle.net/10013/epic.a330f937-84c0-406d-af1e-2100fc605bd9
https://hdl.handle.net/
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Summary:We simulate the two Coupled Model Intercomparison Project scenarios RCP4.5 and RCP8.5, to assess the effects of melt‐induced fresh water on the Atlantic meridional overturning circulation (AMOC). We use a newly developed climate model with high resolution at the coasts, resolving the complex ocean dynamics. Our results show an AMOC recovery in simulations run with and without an included ice sheet model. We find that the ice sheet adds a strong decadal variability on the freshwater release, resulting in intervals in which it reduces the surface runoff by high accumulation rates. This compensating effect is missing in climate models without dynamic ice sheets. Therefore, we argue to assess those freshwater hosing experiments critically, which aim to parameterize Greenland's freshwater release. We assume the increasing net evaporation over the Atlantic and the resulting increase in ocean salinity, to be the main driver of the AMOC recovery.