Sammendrag
Ice Thickness in the Barents Sea: Measurements and Modeling
Hovedfagsoppgave i Oseanografi, 2003
Kandidat: Einar Povl Abrahamsen, Veileder: Tor Gammelsrød
Geofysisk Institutt, UiB

Annual moorings with a current meter and an upward-looking sonar (ULS) were deployed in the Northwestern Barents Sea by the Norwegian Polar Institute from 1993-1996. These yielded three consecutive years of current measurements and two years of ice draft measurements. An interannual difference in the spring mean ice draft of around 80 cm was measured; this is discussed using meteorological information and satellite imagery. There appear to be changes in the wind circulation, which in turn influences the inflow of Atlantic water that largely controls the ice conditions in the Barents Sea. This appears to influence both the ice extent and thickness. The ice draft data are also compared with output from two coupled ice-ocean models.

The ULS is a relatively new instrument type, and data processing still varies widely; this thesis reviews some current ULS data processing algorithms, and a new algorithm, utilizing satellite-derived ice concentrations, is presented. Although in its current form, it is mostly
applicable in the Barents Sea, suggested modifications to this algorithm for more general use in other regions are also given.