Landfast ice affects the stability of the Arctic halocline: Evidence from a numerical model

Landfast ice covers large surface areas of the winter Siberian Seas. The immobile landfast ice cover inhibits divergent and convergent motion, hence dynamical sea ice growth and redistribution, decouples winter river plumes in coastal seas from the atmosphere, and positions polynyas at the landfast...

Full description

Bibliographic Details
Published in:Journal of Geophysical Research: Oceans
Main Authors: Itkin, Polona, Losch, Martin, Gerdes, RĂ¼diger
Format: Article in Journal/Newspaper
Language:unknown
Published: 2015
Subjects:
Online Access:https://epic.awi.de/id/eprint/38037/
https://epic.awi.de/id/eprint/38037/1/itkin-etal_submitted.pdf
https://doi.org/10.1002/2014JC010353
https://hdl.handle.net/10013/epic.45588
https://hdl.handle.net/10013/epic.45588.d001
Description
Summary:Landfast ice covers large surface areas of the winter Siberian Seas. The immobile landfast ice cover inhibits divergent and convergent motion, hence dynamical sea ice growth and redistribution, decouples winter river plumes in coastal seas from the atmosphere, and positions polynyas at the landfast ice edge offshore. In spite of the potentially large effects, state-of-the-art numerical models usually do not represent landfast ice in its correct extent. A simple parametrization of landfast ice based on bathymetry and internal sea ice strength is introduced and its effects on the simulated Arctic Ocean are demonstrated. The simulations suggest that the Siberian landfast ice impacts the Arctic halocline stability through enhanced brine production in polynyas located closer to the shelf break and by redirecting river water to the Canadian Basin. These processes strengthen the halocline in the Canadian Basin, but erode its stability in the Makarov and Eurasian Basins.