Sea ice thickness on basin-scale is an important variable in the polar climate system, however few datasets exists. Remote sensing satellites are the only possibility to accomplish that.

The 2010 launched CryoSat-2 satellite with its on-board Ku-Band radar altimeter (SIRAL) was especially developed for the observation of sea ice.

Radar altimeters measure their distance to the surface and with the knowledge of the sea level elevation one can receive the sea ice freeboard and finally its thickness under assumption of isostatic balance. Significant error sources for the freeboard-thickness conversion are the unknown physical properties of the snow layer, such as depth and density.

The objective of this thesis is to investigate the penetration of the radar waves into the snow and the effect of surface roughness. Therefore it is the goal to compare radar altimeter freeboard data with laser freeboard data and provide a forward model for the backscattered radar echo within a snow layer for a better understanding of the effect of a snow covered sea ice surface on radar altimeter measurements. The final goals are thickness maps of Arctic and Antarctic sea ice and their corresponding errors estimates.

Start of doctoral thesis: 01st July, 2011

Defence of doctoral thesis: 12th March, 2015

Supervisor. Prof. Rüdiger Gerdes
Co-supervisor: Dr. Stefan Hendricks
Further member: Dr. Veit Helm

Committee Meetings: 13.03.12

Programming languages: IDL, MATLAB, Python

LIDAR Workshop in Reykholt, Iceland, 20 June to 21 June 2013

Helmholtz Research School on Earth System Science, Annual Retreat 2012, Bremerhaven, “Deutsches Auswandererhaus“, Poster Presentation: Ricker, R. et al., “Thickness of arctic sea ice and the effect of snow covered sea ice on radar altimeter measurements“ 30 November, 2012

Earth Observation & Cryospehere Science Conference, ESRIN, Frascati, Italy, Talk: “Comparison Of Sea-Ice Freeboard And Thickness Distributions From Aircraft Data And Cryosat-2“, 13-16 November 2012

20 Years of Progress in Radar Altimetry, Venice, Italy, Poster presentation: “Comparison Of Sea-Ice Freeboard Distributions From Aircraft Data And Cryosat-2, 24-29 September 2012“

Polarstern expedition ARKXXVI/3 “TransArc“,Tromsø – Bremerhaven, 05 August – 07 October 2011
CryoVex 2011 Aircraft campaign, Longyearbyen, Spitzbergen, 25-29 March