Ice and ocean velocity in the Arctic marginal ice zone: Ice roughness and momentum transfer

Cole, Sylvia T.; Toole, John M.; Lele, Ratnaksha; Timmermans, Mary-Louise; Gallaher, Shawn G.; Stanton, Timothy P.; Shaw, William J.; Hwang, Byongjun; Maksym, Ted; Wilkinson, Jeremy P. ORCID: https://orcid.org/0000-0002-7166-3042; Ortiz, Macarena; Graber, Hans; Rainville, Luc; Petty, Alek A.; Farrell, Sinéad L.; Richter-Menge, Jackie A.; Haas, Christian. 2017 Ice and ocean velocity in the Arctic marginal ice zone: Ice roughness and momentum transfer. Elementa Science of the Anthropocene, 5, 55. 27, pp. https://doi.org/10.1525/elementa.241

Before downloading, please read NORA policies.

Preview

Text
241-3814-2-PB.pdf - Published Version
Available under License Creative Commons Attribution 4.0.
Download (5MB) | Preview

Official URL: https://doi.org/10.1525/elementa.241

Abstract/Summary

The interplay between sea ice concentration, sea ice roughness, ocean stratification, and momentum transfer to the ice and ocean is subject to seasonal and decadal variations that are crucial to understanding the present and future air-ice-ocean system in the Arctic. In this study, continuous observations in the Canada Basin from March through December 2014 were used to investigate spatial differences and temporal changes in under-ice roughness and momentum transfer as the ice cover evolved seasonally. Observations of wind, ice, and ocean properties from four clusters of drifting instrument systems were complemented by direct drill-hole measurements and instrumented overhead flights by NASA operation IceBridge in March, as well as satellite remote sensing imagery about the instrument clusters. Spatially, directly estimated ice-ocean drag coefficients varied by a factor of three with rougher ice associated with smaller multi-year ice floe sizes embedded within the first-year-ice/multi-year-ice conglomerate. Temporal differences in the ice-ocean drag coefficient of 20–30% were observed prior to the mixed layer shoaling in summer and were associated with ice concentrations falling below 100%. The ice-ocean drag coefficient parameterization was found to be invalid in September with low ice concentrations and small ice floe sizes. Maximum momentum transfer to the ice occurred for moderate ice concentrations, and transfer to the ocean for the lowest ice concentrations and shallowest stratification. Wind work and ocean work on the ice were the dominant terms in the kinetic energy budget of the ice throughout the melt season, consistent with free drift conditions. Overall, ice topography, ice concentration, and the shallow summer mixed layer all influenced mixed layer currents and the transfer of momentum within the air-ice-ocean system. The observed changes in momentum transfer show that care must be taken to determine appropriate parameterizations of momentum transfer, and imply that the future Arctic system could become increasingly seasonal.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	https://doi.org/10.1525/elementa.241
ISSN:	2325-1026
Additional Keywords:	Arctic Ocean, ice-ocean boundary layer, momentum transfer
Date made live:	28 Sep 2017 07:57 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/517949

Item Type:

Publication - Article

Digital Object Identifier (DOI):

https://doi.org/10.1525/elementa.241

ISSN:

2325-1026

Additional Keywords:

Arctic Ocean, ice-ocean boundary layer, momentum transfer

Date made live:

28 Sep 2017 07:57 +0 (UTC)

URI:

https://nora.nerc.ac.uk/id/eprint/517949