Wind-driven mixing at intermediate depths in an ice-free Arctic Ocean

Recent seasonal Arctic Ocean sea ice retreat is a major indicator of polar climate change. The Arctic Ocean is generally quiescent with the interior basins characterized by low levels of turbulent mixing at intermediate depths. In contrast, under conditions of reduced sea ice cover, there is evidenc...

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Bibliographic Details
Published in:Geophysical Research Letters
Main Authors: Lincoln, Ben J., Rippeth, Tom P., Lenn, Yueng-Djern, Timmermans, Mary Louise, Williams, William J., Bacon, Sheldon
Format: Article in Journal/Newspaper
Language:English
Published: 2016
Subjects:
Online Access:http://nora.nerc.ac.uk/id/eprint/515198/
https://nora.nerc.ac.uk/id/eprint/515198/1/Lincoln_et_al-2016-Geophysical_Research_Letters.pdf
https://doi.org/10.1002/2016GL070454
Description
Summary:Recent seasonal Arctic Ocean sea ice retreat is a major indicator of polar climate change. The Arctic Ocean is generally quiescent with the interior basins characterized by low levels of turbulent mixing at intermediate depths. In contrast, under conditions of reduced sea ice cover, there is evidence of energetic internal waves that have been attributed to increased momentum transfer from the atmosphere to the ocean. New measurements made in the Canada Basin during the unusually ice-free and stormy summer of 2012 show previously observed enhancement of internal wave energy associated with ice-free conditions. However, there is no enhancement of mixing at intermediate depths away from significant topography. This implies that contrary to expectations of increased wind-induced mixing under declining Arctic sea ice cover, the stratification in the central Canada Basin continues to suppress turbulent mixing at intermediate depths and to effectively isolate the large Atlantic and Pacific heat reservoirs from the sea surface.