Brief communication: Impacts of a developing polynya off Commonwealth Bay,
East Antarctica, triggered by grounding of iceberg B09B
Christopher J. Fogwill1,2,Erik van Sebille2,3,Eva A. Cougnon4,5,6,Chris S. M. Turney1,2,Steve R. Rintoul4,5,6,Benjamin K. Galton-Fenzi5,7,Graeme F. Clark2,E. M. Marzinelli2,8,Eleanor B. Rainsley9,and Lionel Carter10Christopher J. Fogwill et al. Christopher J. Fogwill1,2,Erik van Sebille2,3,Eva A. Cougnon4,5,6,Chris S. M. Turney1,2,Steve R. Rintoul4,5,6,Benjamin K. Galton-Fenzi5,7,Graeme F. Clark2,E. M. Marzinelli2,8,Eleanor B. Rainsley9,and Lionel Carter10
1PANGEA Research Centre, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, Australia
2Climate Change Research Centre, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, Australia
3Grantham Institute & Department of Physics, Imperial College London, London, UK
4Institute for Marine and Antarctic Studies, University of Tasmania, Private Bag 129, Hobart, Tasmania 7001, Australia
5Antarctic Climate & Ecosystems Cooperative Research Centre, University of Tasmania, Private Bag 80, Hobart, Tasmania 7001, Australia
6Commonwealth Scientific and Industrial Research Organisation, Ocean and Atmospheric Research, Hobart, Tasmania, Australia
7Australian Antarctic Division, Kingston, Tasmania, Australia
8Centre for Marine Bio-Innovation, School of Biological, Earth and Environmental Sciences, UNSW ,Sydney, Australia
9Wollongong Isotope Geochronology Laboratory, School of Earth and Environmental Sciences, University of Wollongong, Wollongong, Australia
10Antarctic Research Centre, Victoria University of Wellington, Wellington, New Zealand
1PANGEA Research Centre, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, Australia
2Climate Change Research Centre, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, Australia
3Grantham Institute & Department of Physics, Imperial College London, London, UK
4Institute for Marine and Antarctic Studies, University of Tasmania, Private Bag 129, Hobart, Tasmania 7001, Australia
5Antarctic Climate & Ecosystems Cooperative Research Centre, University of Tasmania, Private Bag 80, Hobart, Tasmania 7001, Australia
6Commonwealth Scientific and Industrial Research Organisation, Ocean and Atmospheric Research, Hobart, Tasmania, Australia
7Australian Antarctic Division, Kingston, Tasmania, Australia
8Centre for Marine Bio-Innovation, School of Biological, Earth and Environmental Sciences, UNSW ,Sydney, Australia
9Wollongong Isotope Geochronology Laboratory, School of Earth and Environmental Sciences, University of Wollongong, Wollongong, Australia
10Antarctic Research Centre, Victoria University of Wellington, Wellington, New Zealand
Correspondence: Christopher J. Fogwill (c.fogwill@unsw.edu.au)
Received: 22 Jan 2016 – Discussion started: 07 Mar 2016 – Revised: 23 Sep 2016 – Accepted: 14 Oct 2016 – Published: 04 Nov 2016
Abstract. The dramatic calving of the Mertz Glacier tongue in 2010, precipitated by the movement of iceberg B09B, reshaped the oceanographic regime across the Mertz Polynya and Commonwealth Bay, regions where high-salinity shelf water (HSSW) – the precursor to Antarctic bottom water (AABW) – is formed. Here we present post-calving observations that suggest that this reconfiguration and subsequent grounding of B09B have driven the development of a new polynya and associated HSSW production off Commonwealth Bay. Supported by satellite observations and modelling, our findings demonstrate how local icescape changes may impact the formation of HSSW, with potential implications for large-scale ocean circulation.
Here we report new data from in situ oceanographic surveys and high-resolution ocean modelling experiments in the Commonwealth Bay region of East Antarctica, where in 2010 there was a major reconfiguration of the regional icescape due to the collision of the 97 km long iceberg B09B with the Mertz Glacier tongue. Here we compare post-calving observations with high-resolution ocean modelling which suggest that this reconfiguration has led to the development of a new polynya off Commonwealth Bay.
Here we report new data from in situ oceanographic surveys and high-resolution ocean modelling...
