| Summary: | Abstract: In recent years, warmer Atlantic-origin waters have intruded into Svalbard's westcoast fjords. To predict the effect of the TAW (transformed Atlantic water) intrusion on the ice margin of tidewater glaciers, a detailed understanding of fjord circulation is important. While the general fjord circulation of Kongsfjorden, Svalbard, is well understood, water masses closest to the ice margin {and directly responsible for submarine glacial melt {are more difficult to study. To characterize the water masses and interpret fjord circulation at the calving-fronts of glaciers Kronebreen and Kongsvegen, Svalbard, oceanographic fieldwork was conducted along five primary transects, with the view to account for tidal influences as well. CTD (conductivity, temperature, depth) devices with attached OBS (relative turbidity) sensors were used to collect data that range from 200 m to 1.7 km from the ice face, between 22 Jul and 6 Aug 2011. Current velocities were also estimated using drogues constructed while in Svalbard. The data show significantly variability in the water column stratification between just days. In addition to the tidal cycle, winds and other factors also appear to play a major role in glacial discharge streams and circulation. A comparison with data collected in the same region in Jul 2005 (by Trusel et al. 2010) show the 2011 Intermediate Water (IW) at depth to be warmer than the 0 local water (LC) that was observed at comparable depths in 2005. These two layers lie above the TAW and may be warmer as a result of convection with increased TAW waters. Increased intrusion of Atlantic-origin waters after 2005 are likely to have warmed the waters in the inner fjord of Kongsfjorden, indicating that the ice margin of tidewater glaciers in Kongsfjorden are susceptible to heat fluxes from North Atlantic water intrusions.
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