On the problem of parameterizing ice shelf-ocean interaction in global climate models


Contact
hhellmer [ at ] awi-bremerhaven.de

Abstract

Sensitivity studies for the Southern Ocean indicate that freshwater fluxes from various sources have a significant impact on the stability of the water column with consequences for sea ice and water mass characteristics. These sources are either atmospheric or result from ocean interaction with the base of Antarctic ice shelves and drifting icebergs. The resolution of global climate models does not allow for an adequate representation of the processes on polar continental shelves. Therefore, model deficits exist in terms of sea ice thickness, and water salinities and temperatures in regions important for the composition of the deep water participating in the global thermohaline circulation. In view of these deficits, Beckmann and Goosse [2003] parameterized the freshwater flux from major Antarctic ice shelf cavities in a global climate model calculating the net ocean-ice shelf heat flux as a combination of subsurface temperature at the continental shelf break and an effective basal area of melting. This study shows that a parameterization of the sub-ice freshwater flux is problematic because of the missing direct link to continental slope temperatures, major regional differences, and dependencies on the thickness of the shelf water column considered. Therefore, the only suitable way today might be prescribing the freshwater fluxes determined by regional coupled ice-ocean models like BRIOS at the southern boundary of large-scale global models corresponding to ice shelf fronts.



Item Type
Article
Authors
Divisions
Programs
Peer revision
Not peer-reviewed
Publication Status
Published
Eprint ID
11543
Cite as
Hellmer, H. (2005): On the problem of parameterizing ice shelf-ocean interaction in global climate models , Forum for Research into Ice Shelf Processes (FRISP) Report No. 16, pp. 27-31 .


Download
[img]
Preview
PDF (Fulltext)
Hel2005a.pdf

Download (1MB) | Preview
Cite this document as:

Share

Research Platforms
N/A

Campaigns


Actions
Edit Item Edit Item