Ice-ocean-atmosphere interactions in the western Weddell Sea: Coastal polynyas, cyclones and bottom water formation

Applicants

Professor Dr. Günther Heinemann 
Universität Trier
Fachbereich VI - Raum- und Umweltwissenschaften
Fach Umweltmeteorologie

Dr. Ralph Timmermann 
Alfred-Wegener-Institut
Helmholtz-Zentrum für Polar- und Meeresforschung

Project Description

Coastal polynyas play an important role for the coupling between the components of the sea ice-oceanatmosphere system in polar areas. Locally enhanced surface exchange processes in areas of open water have important consequences for the atmosphere, ocean processes, ice formation (brine release), gas exchange and biology. In the Weddell Sea, recurrent coastal polynyas form at the Filchner-Ronne ice shelf and in the area of the recently collapsed Larsen A/B ice shelves, both largely triggered by atmospheric forcing. The project aims at an improved understanding of the polynja formation processes, and the quantification of the bottom water formation and ice production associated with coastal polynyas for the Weddell Sea area. A coupled system of the non-hydrostatic weather forecast model COSMO (German Meteorological Service, DWD) and the sea ice-ocean model FESOM (AWI) will be used at a high resolution. Simulations with a resolution of 5 km will be run over a whole winter period. The forcingby synoptic-scale cyclones and mesoscale processes (such as katabatic winds and mesocyclones) and their interaction with the polynyas will be investigated. Of particular interest is the possible change of bottom water formation in the former Larsen ice shelf area.

Final Report

DFG Programme: Infrastructure Priority Programmes

Term from 2008 to 2013