Guy Williams

Bathymetric control of warm ocean water access along the East Antarctic Margin

Publisher: American Geophysical Union (AGU)

Date: 07-09-2017

DOI: 10.1002/2017GL074433

Dense shelf water spreading from Antarctic coastal polynyas to the deep Southern Ocean: A regional circumpolar model study

Publisher: American Geophysical Union (AGU)

Date: 08-2017

DOI: 10.1002/2017JC012911

Carbon cycling dynamics in the seasonal sea-ice zone of East Antarctica

Publisher: American Geophysical Union (AGU)

Date: 12-2016

DOI: 10.1002/2016JC012008

Freshening by glacial meltwater enhances melting of ice shelves and reduces formation of Antarctic Bottom Water

Publisher: American Association for the Advancement of Science (AAAS)

Date: 06-04-2018

DOI: 10.1126/SCIADV.AAP9467

Abstract: Glacial meltwater stops bottom-water formation, allowing warm ocean waters to reach Antarctic ice shelves and drive rapid melting.

Acoustic Search and Detection of Oil Plumes Using an Autonomous Underwater Vehicle

Publisher: MDPI AG

Date: 17-08-2020

DOI: 10.3390/JMSE8080618

Abstract: We introduce an adaptive s ling method that has been developed to support the Backseat Driver control architecture of the Memorial University of Newfoundland (MUN) Explorer autonomous underwater vehicle (AUV). The design is based on an acoustic detection and in-situ analysis program that allows an AUV to perform automatic detection and autonomous tracking of an oil plume. The method contains acoustic image acquisition, autonomous triggering, and thresholding in the search stage. A new biomimetic search pattern, the bumblebee flight path, was designed to maximize the spatial coverage in the oil plume detection phase. The effectiveness of the developed algorithm was validated through simulations using a two-dimensional planar plume model and a 90-degree scanning sensor model. The results demonstrate that the bumblebee search design combined with a genetic solution for the Traveling Salesperson Problem outperformed a conventional lawnmower survey, reducing the AUV travel distance by up to 75.3%. Our plume detection strategy, using acoustic sensing, provided data of plume location, distribution, and density, over a sector in contrast with traditional chemical oil sensors that only provide readings at a point.

Warm Modified Circumpolar Deep Water Intrusions Drive Ice Shelf Melt and Inhibit Dense Shelf Water Formation in Vincennes Bay, East Antarctica

Publisher: American Geophysical Union (AGU)

Date: 30-07-2021

DOI: 10.1029/2020JC016998

Abstract: Antarctic Bottom Water (AABW) production supplies the deep limb of the global overturning circulation and ventilates the deep ocean. While the Weddell and Ross Seas are recognized as key sites for AABW production, additional sources have been discovered in coastal polynya regions around East Antarctica, most recently at Vincennes Bay. Vincennes Bay, despite encompassing two distinct polynya regions, is considered the weakest source, producing Dense Shelf Water (DSW) only just dense enough to contribute to the lighter density classes of AABW found offshore. Here we provide the first detailed oceanographic observations of the continental shelf in Vincennes Bay (104‐111°E), using CTD data from instrumented elephant seals spanning from February to November of 2012. We find that Vincennes Bay has East Antarctica’s warmest recorded intrusions of modified Circumpolar Deep Water (mCDW) and that warm mCDW drives basal melt under Vanderford and Underwood ice shelves. Our study also provides the first direct observational evidence for the inflow of meltwater to this region, which increases stratification and hinders DSW formation, and thus AABW production. The Vincennes Bay glaciers, together with the Totten Glacier, drain part of the Aurora Basin, which holds up to 7 m of sea level rise equivalent. Our results highlight the vulnerability of the East Antarctic Ice Sheet to intrusions of mCDW.

Reduced Sea Ice Production Due to Upwelled Oceanic Heat Flux in Prydz Bay, East Antarctica

Publisher: American Geophysical Union (AGU)

Date: 02-05-2019

DOI: 10.1029/2018GL081463

Regional Changes in Icescape Impact Shelf Circulation and Basal Melting

Publisher: American Geophysical Union (AGU)

Date: 18-11-2017

DOI: 10.1002/2017GL074943

Seasonality of Warm Water Intrusions Onto the Continental Shelf Near the Totten Glacier

Publisher: American Geophysical Union (AGU)

Date: 06-2019

DOI: 10.1029/2018JC014634

Distribution of water masses and meltwater on the continental shelf near the Totten and Moscow University ice shelves

Publisher: American Geophysical Union (AGU)

Date: 03-2017

DOI: 10.1002/2016JC012115

University Of Tasmania

Location: Australia

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University Of Sydney

Location: Australia

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Computer Power Training Institute

Location: Australia

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ARC Future Fellowships - Grant ID: FT130100692

Start Date: 06-2014

End Date: 06-2022

Amount: $755,320.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP170103774

Start Date: 2017

End Date: 12-2022

Amount: $246,500.00

Funder: Australian Research Council

Special Research Initiatives - Grant ID: SR200100008

Start Date: 08-2021

End Date: 12-2027

Amount: $20,000,000.00

Funder: Australian Research Council