University Of Tasmania

File(s) not publicly available

Sea-ice growth and water mass modification in the Mertz Glacier Polynya, East Antarctica, during winter

journal contribution
posted on 2023-05-16, 16:43 authored by Nathaniel BindoffNathaniel Bindoff, Guy Williams, Ian AllisonIan Allison
In July-September 1999, an extensive oceanographic survey (87 conductivity-, temperature- and depth-measuring stations) was conducted in the Mertz Glacier polynya over the Adélie Depression off the Antarctic coast between 145° and 150° E. We identify and describe four key water masses in this polynya: highly modified circumpolar deep water (HMCDW), winter water (WW), ice-shelf water (ISW) and high-salinity shelf water (HSSW). Combining surface velocity data (from an acoustic Doppler current-profiler) with three hydrographic sections, we found the HMCDW to be flowing westward along the shelf break (0.7 Sv), the WW and HSSW flowing eastwards underneath Mertz Glacier (2.0 Sv) and that there was a westward return flow of ISW against the continent (1.2 Sv). Using a simple box model for the exchanges of heat and fresh water between the principal water masses, we find that the polynya was primarily a latent-heat polynya with 95% of the total heat flux caused by sea-ice formation. This heat flux results from a fresh-water-equivalent sea-ice growth rate of 4.9-7.7 cm d1 and a mass exchange between HMCDW and WW of 1.45 Sv The inferred ocean heat flux is 8-14 W m2 and compares well with other indirect estimates.


Publication title

Annals of Glaciology








School of Natural Sciences


International Glaciological Society

Place of publication

Cambridge, England

Repository Status

  • Restricted

Socio-economic Objectives

Social impacts of climate change and variability

Usage metrics

    University Of Tasmania