Investigation of Small Scale Polynya and Sea Ice Dynamics using TerraSAR-X Dual Polarisation Strip Map Mode Data
Thomas Krumpen(1), Thomas Busche(2), Lasse Rabenstein(1), Sascha Willmes(3), Christian Haas(4), Irena Hajnsek(2) and Jens Hoelemann(1)
(1) Alfred Wegener Institute (AWI), Busse Str. 24, 27570 Bremerhaven, Germany
(2) German Aerospace Center (DLR), e.V., P.O. Box 1116, 82234 Wessling, Germany
(3) University of Trier, Behringstr. 21, 54286 Trier, Germany
(4) University of Alberta, 1-26 Earth Sciences Building, Edmonton, Alberta, T6G 2E3, Canada
In recognition of its importance and its barely explored state, the Eastern Laptev Sea in general and the West New Siberian (WNS) polynya in particular have been subject of several Russian-German research projects in the framework of studies of the “Laptev Sea System”. Ice formation, salt rejection and the role of the WNS polynya for Arctic Ocean water mass modification were further investigated within the framework of the ESA project EO 500 and COA_0388 (“Investigating Dynamics, Evolution, and Polarimetric Properties of Arctic Coastal Polynyas and Sea Ice Using TerraSAR-X Data”) in the winter season of 2007/2008 by means of remote sensing observations and polynya flux model computations.
Polynya flux models are widely used to estimate resultant ice and salt fluxes. However, a drawback with all flux models is that they characterize frazil and consolidated ice types by their depth distributions and do not include an ice concentration field. Therefore, further research on parameterisations for the collection depth of frazil ice and ice concentration in open water and thin ice zones is urgently required.
The investigation of small scale ice features requires a high resolution SAR sensor with the capability to discriminate reliably between open water, regions of frazil ice accumulation, and consolidated thin ice. A potential candidate to further investigate the collection depth, the distribution of frazil ice and ice concentration in thin ice zones is TerraSAR-X. Especially dual polarised data in strip map mode may discriminate water surfaces from young and thin ice, and the high resolution of the X-band SAR sensor may help to resolve small-scale thin ice processes taking place.
Here we present first results of a comparison of dual polarised TerraSAR-X data with C-band ENVISAT ASAR imagery in wide swath mode, optical data from the MODIS sensor, helicopter-borne sea ice thickness from electromagnetic profiling, and aerial photo observations. The data set was obtained during TRANSDRIFT XIII expedition in April, 2008 in the Laptev Sea.