Hydrography of Marian Cove, King George Island, West Antarctica: implications for ice-proximal sedimentation during summer

Abstract

During austral summers from 1996 to 2000, vertical profiles of conductivity, temperature, and transmissivity were obtained near the tidewater glacier of Marian Cove, King George Island, Antarctic Peninsula, to determine the short-term variations of water structure due to hydrographic forcings and to understand sedimentation of suspended particulate matter in Antarctic fjord environments. Four distinct water layers were recognized in the ice-proximal zone of the cove: 1) a surface layer composed of cold and turbid meltwater, 2) a relatively warm Maxwell Bay inflow layer with characteristics of outer fjord water, 3) a turbid/cold mid-depth layer (40 to 70 m water depth) originating from subglacial discharge, and 4) a deep layer comprised of the remnant winter water. The main factor influencing the characteristics of glacial meltwater layers and driving deposition of suspended particles in the cove is tidal forcing coupled with wind stress. The relatively small amount of meltwater discharge in Marian Cove yield low accumulation rates of non-biogenic sedimentary particles in the cove. A northwestern and western wind effects coupled with flood tide may promote settling and sedimentation of suspended particles from turbid layers in the ice-proximal zone of the cove.