Winter Mixed Layer Restratification Induced by Vertical Eddy Buoyancy Flux in the Labrador Sea

Abstract Numerical model studies have shown that the lateral buoyancy transports from eddies restratify the convection region in the Labrador Sea. However, restratification by vertical motion during and after convection has been underestimated. Here we use a model with 1°/60° resolution which can re...

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Bibliographic Details
Published in:Geophysical Research Letters
Main Authors: Pusheng Li, Ruiyi Chen, Ruijian Gou, Clark Pennelly, Yiyong Luo, Paul G. Myers
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 2023
Subjects:
Online Access:https://doi.org/10.1029/2023GL103341
https://doaj.org/article/83015012b3a241a9815f7077b3236e50
Description
Summary:Abstract Numerical model studies have shown that the lateral buoyancy transports from eddies restratify the convection region in the Labrador Sea. However, restratification by vertical motion during and after convection has been underestimated. Here we use a model with 1°/60° resolution which can resolve mesoscale and submesoscale motions, and find that negative feedback that includes the generation of vertical eddy buoyancy flux (VEBF) committed to restratify the mixed layer. In winter, VEBF compensates for nearly half of the surface buoyancy loss and is as important as the lateral buoyancy fluxes in the eddy‐rich region, which results in restraining the development of deep convection. During this period, the surge of VEBF was due to seasonally enhanced frontogenesis, mixed layer instability and the interaction between strong surface winds and eddies on a 10‐day timescale. Therefore, well parameterizing VEBF is important in improving the representation of the deep convection in coarse‐grid climate models.