Supercooling of Seawater Near the Glacier Front in a Fjord

Abstract

We analyze seawater temperature and salinity in the immediate vicinity of the Paulbreen front in Spitsbergen. The CTD-measurements were carried out from ice in winter and from a boat in summer. ADCP profiling was performed near the glacier front from the ice in winter. In winter, we found water with lower salinity than the surrounding water in the fjord at a distance of 15 m from the glacier front and recorded a low upward water flux near the glacier. Relatively fresh water was found at a depth of 2-4 m near the glacier front in the place where the sea and glacier bed have local depression up to 17 m. Supercooling of the freshened water reached 0.35°C. We link this phenomenon to a flow of freshwater from under a polythermal glacier. This water becomes overcooled in the seawater with significantly lower temperature and higher salinity.

Distribution of cold and temperate ice and water in glaciers at Nordenskiöld Land, Svalbard, according to data on ground-based radio-echo sounding

“…Subglacial water run-off leading to desalination of sea water was detected in winter near the ice front of Tunabreen (Muzylev et al 2013). Taking into account that in Svalbard there are 163 tidewa-ter glaciers with a total ice-front length of 860 km (Błaszczyk et al 2009), subglacial run-off can have a remarkable influence on the spread of sea ice in adjoining fjords (Marchenko et al 2017).…”