Speaker

Liv Cornelissen, Ph.D. student, Univ. of Auckland

Oceanic Influences of the Drygalski Ice Tongue in Terra Nova Bay: An Observational Perspective

Abstract

The Drygalski Ice Tongue (DIT), located in the western Ross Sea, is the largest remaining ice tongue and forms the southern boundary of Terra Nova Bay (TNB) and enables it to operate as a polynya by preventing the transport of sea ice into the bay from the south. The surrounding water masses interact with the DIT, and changes in their properties can influence the tongue’s stability. In this talk, I will present findings from a decade-long hydrographic mooring timeseries (DITx), deployed near the DIT and in the Drygalski Trough. This dataset captures variability across interannual, seasonal, and polynya-event timescales. Water masses that are formed in Terra Nova Bay and are observed near the DIT are high salinity shelf water (HSSW), TNB ice shelf water (ISW) and Antarctic surface water (ASW) and form the seasonal cycle. The interannual variability is particularly evident in the timing of seasonal transitions and in long-term temperature and salinity trends. I will also discuss the connectivity between the DITx record and other regional datasets, including Mooring D and ARGO floats.