Project

4511

Chief Investigator

ROBERTS, Dr Jason - Australian Antarctic Division

Title

ICECAP - EAGLE

Project aims

This airborne geophysics and oceanography project explores the stability of the Antarctic ice sheet and the associated consequences for global sea-level rise. We will focus on ice sheet/ocean interactions including the first large scale simultaneous measurement of East Antarctic continental shelf ocean properties relevant to the stability of the fringing ice shelves. We will also conduct detailed surveys of the Shackleton Ice Shelf (the most northerly ice shelf outside the Antarctic Peninsula) and the George V Coast, two under-surveyed areas with significant sea-level rise potential.

We will continue to survey the interior of the ice sheet, building on the altimetry time series built up over 10 field seasons, and contribute to calibration and validation activities for satellite altimetry missions. The prevalence, distribution and impact of subglacial water on ice sheet stability will also be a key area of study.

Project gallery


Project Summary of the Season 2019/20

The planned 2019/20 field season for AAS 4511 (ICECAP EAGLE) was to establish a baseline for spatial variability in the continental shelf ocean properties, and undertake a broad-scale survey of the coastal bythmetry covering the entire coastal Australian Antarctic Territory. This information is vital for accurate assessment of the vulnerability of the Antarctic ice sheet to changing oceanic conditions, and predictions of the future response of the ice sheet.

Due to Antarctic operational logistical constraints, ICECAP EAGLE was unable to undertake this ambitious plan which would have involved support from Casey, Davis and Mawson along with support from foreign stations including Zucchelli, DDU and Syowa.

We plan on attempting this survey of the entire coastal Australian Antarctic Territory in a future field season, as data from this survey is essential for planning the more detailed surveys based out of Bunger Hills and Oates/George V Coast remote skiways originally planned for the 2020/21 and 2021/22 field seasons.

Project Summary of the Season 2022/23

Due to logistical constrains no field work in support of AAS 4511 (ICECAP - EAGLE) was undertaken in the 2022/23 season. However, analysis of legacy data from previous associated AAS projects (3103, 4077 and 4346) resulted in the publication of three peer-reviewed journal papers. A key paper on the structural evolution of the Shackleton Ice Shelf directly contributes to our understanding of ice shelf state and stability, while a second paper enhances our knowledge of ice sheet basal boundary conditions, which ultimately control the discharge of grounded ice into the ocean and contribute to local and global sea-level change.

ICECAP - EAGLE has been a keystone collaborator in the SCAR RINGS initiative to consistently map the Antarctic ice sheet grounding zone, to enable better current estimates and future projections of the ice sheet mass balance and contribution to local and global sea-level change. Detailed internationally collaborative field season planning has been undertaken to jointly survey the grounding zone in Enderby Land, currently the region with the sparest ground zone mapping.

In addition, ICECAP - EAGLE has also been involved in preliminary field planning for a potential 2023/24 field season, and in particular liaising with the Denman Terrestrial field campaign to optimise ICECAP flights in the region to complement and enhance their ground and helicopter based studies.

Category 1: Peer-reviewed literature

Noble T.L., Rohling E.J., Aitken A.R.A., Bostock H.C., Chase Z., Gomez N., Jong L.M., Roberts J.L. (2020) The Sensitivity of the Antarctic Ice Sheet to a Changing Climate Past Present and Future, Reviews of Geophysics .; [Ref: 16337]

Cui X., Jeofry H., Greenbaum J.S., Guo J., Li L., Lindzey L.E., Habbal F.A., Wei W., Young D.A., Ross N., Morlighem M., Jong L.M., Roberts J.L., Blankenship D.D., Bo S., Siegert M.J. (2020) Bed topography of Princess Elizabeth Land in East Antarctica, Earth System Science Data 2765–2774; [Ref: 16338]

McCormack F.S., Roberts J. L., Gwyther D.E., Morlighem M., Pelle T., Galton-Fenzi B.K. (2021) The impact of variable ocean temperatures on Totten Glacier stability and discharge, Geophysical Research Letters 48. .; [Ref: 16415]

Yan S., Blankenship D., Greenbaum J., Young D., Li L., Rutishauser A., Guo J., Roberts J., van Ommen T., Siegert M., Sun B. (2022) A newly discovered subglacial lake in East Antarctica likely hosts a valuable sedimentary record of ice and climate change, Geology .; [Ref: 16444]

McCormack F.S., Warner R.C., Seroussi H., Dow C.F., Roberts J.L., Treverrow A. (2022) Modeling the deformation regime of Thwaites Glacier, West Antarctica, using a simple flow relation for ice anisotropy (ESTAR), Journal of Geophysical Research: Earth Surface .; [Ref: 16468]

Wolff E.W., Fischer H., van Ommen T., Hodell D.A (2022) Stratigraphic templates for ice core records of the past 1.5 Myr, Climate of the Past .; [Ref: 16542]

Yang J., Guo J., Greenbaum J.S., Cui X., Jong L.M., Roberts J.L., van Ommen T.D. (2021) Bathymetry beneath the Amery Ice Shelf, East Antarctica, revealed by airborne gravity, Geophysical Research Letters .; [Ref: 16546]

Craw L., McCormack F.S., Cook S., Roberts J., Treverrow A. (2022) Modelling the influence of marine ice on the dynamics of an idealised ice shelf, Journal of Glaciology .; [Ref: 16590]

McCormack F.S., Roberts J.L., Dow C., Stal T., Halpin J.A., Reading A.M., Siegert M.J. (2022) Fine-scale geothermal heat flow in Antarctica can increase simulated subglacial melt estimates, Geophysical Research Letters .; [Ref: 16591]