Hydrographic Observations in the Northwestern Weddell Sea Marginal Ice Zone during March 1986

摘要

Temperature and salinity observations were made from the surface down to 1500 m, in the central northwestern Weddell Sea, during March 1986. These observations sampled the three water masses characterizing the region. The uppermost, Surface Water, layer extended down to 30-50 m, had temperatures from near freezing (-1.8C) up to about OC and salinities of 33-34 ppt. A layer of Weddell Winter Water underlay the Surface Water, extending down to about 100m, and had temperatures of -1.5 to -1.7C and a salinity of about 34.46 ppt. The Weddell Warm Deep Water extended from the bottom of the Winter Water down to more than 1500m, displaying temperature increasing with depth to a maximum of about 0.5C near 500m then decreasing down to 1500m. The temperature maximum region within the Warm Deep Water decreased in depth eastward, toward the center of the gyre, within the core. The baroclinic circulation, expressed as dynamic topography of the surface relative to the 1500 db level, was insignificant throughout the region.