Regensburg 2010 – wissenschaftliches Programm
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DY: Fachverband Dynamik und Statistische Physik
DY 30: Posters II
DY 30.33: Poster
Donnerstag, 25. März 2010, 16:00–18:00, Poster C
Modeling the morphogenesis of brine channels in sea ice — Bernd Kutschan1, •Klaus Morawetz2,3, and Sibylle Gemming4 — 1Ident Technologies GmbH, Rudower Chaussee 29, 12489 Berlin, Germany — 2University of Applied Science Münster, Stegerwaldstrasse 39, 48565 Steinfurt, Germany — 3International Center for Condensed Matter Physics, Universidade de Brasília, 70904-910, Brasília-DF, Brazil — 4Forschungszentrum Dresden-Rossendorf, PF 51 01 19, 01314 Dresden, Germany
Brine channels are formed in sea ice under certain constraints and represent a habitat of different microorganisms. The complex system depends on a number of various quantities as salinity, density, pH-value or temperature. Each quantity governs the process of brine channel formation. There exists a strong link between bulk salinity and the presence of brine drainage channels in growing ice with respect to both the horizontal and vertical planes. We develop a suitable phenomenological model for the formation of brine channels both referring to the Ginzburg-Landau-theory of phase transitions as well as to the chemical basis of morphogenesis according to Turing. It is possible to conclude from the critical wavenumber on the size of the structure and the critical parameters. The theoretically deduced transition rates have the same magnitude as the experimental values. The model creates channels of similar size as observed experimentally. An extension of the model towards channels with different sizes is possible. The microstructure of ice determines the albedo feedback and plays therefore an important role for large-scale global circulation models (GCMs).