AMOC variability and watermass transformations in the AWI climate model

Using the depth (z) and density (ϱ) frameworks, we analyze local contributions to AMOC variability in a 900-year simulation with the AWI climate model. Both frameworks reveal a consistent interdecadal variability; however, the correlation between their maxima deteriorates on year-to-year scales. We...

Full description

Bibliographic Details
Published in:Journal of Advances in Modeling Earth Systems
Main Authors: Sidorenko, Dmitry, Danilov, Sergey, Streffing, Jan, Fofonova, Vera, Goessling, Helge, Scholz, Patrick, Wang, Qiang, Androsov, Alexey, Cabos, William, Juricke, Stephan, Koldunov, Nikolay, Rackow, Thomas, Sein, Dmitry, Jung, Thomas
Format: Article in Journal/Newspaper
Language:unknown
Published: 2021
Subjects:
Online Access:https://epic.awi.de/id/eprint/54687/
https://doi.org/10.1029/2021MS002582
https://hdl.handle.net/10013/epic.6c1a9517-9354-474b-9b1a-5f774ab87381
Description
Summary:Using the depth (z) and density (ϱ) frameworks, we analyze local contributions to AMOC variability in a 900-year simulation with the AWI climate model. Both frameworks reveal a consistent interdecadal variability; however, the correlation between their maxima deteriorates on year-to-year scales. We demonstrate the utility of analyzing the spatial patterns of sinking and diapycnal transformations through depth levels and isopycnals. The success of this analysis relies on the spatial binning of these maps which is especially crucial for the maps of vertical velocities which appear to be too noisy in the main regions of up- and downwelling because of stepwise bottom topography. Furthermore, we show that the AMOC responds to fast (annual or faster) fluctuations in atmospheric forcing associated with the NAO. This response is more obvious in the ϱ than in the z framework. In contrast, the link between AMOC deep water production south of Greenland is found for slower fluctuations and is consistent between the frameworks.