Sea ice is an important element affecting the climate of the polar regions and its interaction with the atmosphere and the ocean has a deep impact on the global climate system. In particular the drift of sea ice, which strongly depends on the wind stress from the atmosphere and on the ocean currents, enhances the transport of fresh water out of the Arctic ocean and the formation of new areas of open water.
The present state-of-the-art sea-ice models are able to reasonably reproduce the extent of the sea ice and the major processes of the interaction with atmosphere and ocean but work is still needed to better understand and parameterize small scale processes like ice ridges and the effects of ice roughness on atmosphere-ice-ocean interaction.
The objective of this thesis is to study the effect of the wind stress on a rough surface and on the dynamics of ice floes. Analyzing the movement of rough ice on the ocean will provide information on the Ekman transport and thus on the global circulation and on the transport of tracers in the ocean. A better understanding of these processes allows a parameterization that will enhance large-scale global circulation models.


Start of doctoral thesis: 1st September 2011

Defence of doctoral thesis: 14th November 2014

Supervisor : Prof. Dr. Rüdiger Gerdes

Further members : Dr. Martin Losch, Dr. Christof Lüpkes

Helmholtz Research School on Earth System Science, Annual Retreat 2012, Bremerhaven, “Deutsches Auswandererhaus“, Poster Presentation: Castellani, G et al., “Impact of sea-ice surface roughness on the momentum exchange between atmosphere, sea ice and oceans“ 30 November, 2012.

Programming tools / data analysis tools used / computational skills:
Fortran, Linux, LaTex