Accession Number : ADA328670

Title :   The Barents Sea Polar Front in Summer,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF OCEANOGRAPHY

Personal Author(s) : Parsons, A. R. ; Bourke, Robert H. ; Muench, Robin D. ; Chiu, Ching-Sang ; Lynch, James F.

Report Date : 15 JUN 1996

Pagination or Media Count : 21

Abstract : In August 1992 a combined physical oceanography and acoustic tomography experiment was conducted to describe the Barents Sea Polar Front (BSPF) and investigate its impact on the regional oceanography. The study area was an 80 X 70 km grid east of Bear Island where the front exhibits topographic trapping along the northern slope of the Bear Island Trough. Conductivity-temperature-depth, current meter, and acoustic Doppler current profiler (ADCP) data, combined with tomographic cross sections, presented a highly resolved picture of the front in August. All hydrographic measurements were dominated by tidal signals, with the strongest signatures associated with the M2 and 52 semidiurnal species. Mean currents in the warm saline water to the south of the front, derived from a current meter mooring and ADCP data, were directed to the southwest and may be associated with a barotropic recirculation of Norwegian Atlantic Water (NAW) within the Bear Island Trough. The geostrophic component of the velocity was well correlated with the measured southwestward mean surface layer flow north of the front. The frontal structure was retrograde, as the frontal isopleths sloped opposite to the bathymetry. The surface signature of the front was dominated by salinity gradients associated with the confluence of Atlantic and Arctic water masses, both warmed by insolation to a depth of about 20 m. The surface manifestation of the front varied laterally on the order of 10 km associated with tidal oscillations. Below the mixed layer, temperature and salinity variations were compensating, defining a nearly barotropic front. The horizontal scale of the front in this region was ^3 km or less. At middepth beneath the frontal interface, tomographic cross sections indicated a high-frequency (^16 cpd) upslope motion of filaments of NAW origin.

Descriptors :   *WATER MASSES, *OCEANOGRAPHY, REPRINTS, ACOUSTIC WAVES, BATHYMETRY, TIDAL CURRENTS, ATLANTIC OCEAN, SALINITY, NORWAY, HYDROGRAPHY, SEA WATER, GEOSTROPHIC CURRENTS, GEOSTROPHIC WIND, COMPUTERIZED TOMOGRAPHY, SUMMER, ARCTIC REGIONS, MOORING, RECIRCULATION.

Subject Categories : Physical and Dynamic Oceanography

Distribution Statement : APPROVED FOR PUBLIC RELEASE