Impacts of model biases on the pathways of the subpolar North Atlantic overturning circulation in a hierarchy of ocean hindcasts ...

• Main Authors: Tooth, Oliver, Johnson, Helen, Wilson, Chris
• Format: Conference Object
• Language: unknown
• Published: GFZ German Research Centre for Geosciences 2023
• Subjects: North Atlantic
• Online Access: https://dx.doi.org/10.57757/iugg23-1806; https://gfzpublic.gfz-potsdam.de/pubman/item/item_5017781

<!--!introduction!--> The introduction of high-resolution ocean model simulations has significantly improved the fidelity of the pathways constituting the Atlantic Meridional Overturning Circulation (AMOC) at subpolar latitudes. However, the progression from eddy-parameterised to eddy-rich ocean models has also introduced new biases in the subpolar North Atlantic, including larger-than-observed dense water formation over the Subpolar Gyre (SPG). Here, we use Lagrangian trajectories initialised across the Overturning in the Subpolar North Atlantic Program (OSNAP) array to explore the influence of these biases on the structure of the subpolar AMOC in three ocean hindcast simulations at resolutions ranging from 1º to 1/12º. We show that the strength of the AMOC simulated across OSNAP increases substantially with increasing model resolution. The stronger overturning found at high resolution is explained by an intensification of the SPG, which yields greater dense water formation along the boundary ... : The 28th IUGG General Assembly (IUGG2023) (Berlin 2023) ...