Airborne sea-ice thickness: Synoptic spring-time assessment

The Antarctic sea ice plays a crucial role in the Antarctic climate and eco-systems and is closely linked to under shelf ice-ocean processes. We propose an airborne electromagnetic (AEM) survey of pack-ice and fast-ice thickness in the Prydz Bay based out of Davis Station to observe the regional sea-ice characteristics, and to quantify the amount of sea-ice exported from small polynyas along the coast. Such a survey is crucial considering the dramatic changes in the high latitudes, especially the dramatic 2023 winter deficit of Antarctic sea ice, with direct effect on ocean-ice-atmosphere dynamic and thermodynamic processes. In addition, we seek to detect the presence (and thickness) of any platelet layer under the fast ice. While there have been few direct observations of platelet ice off East Antarctica, its detection would reveal the presence of previously unmapped supercooled water originating from the bottom melt of ice shelves, providing evidence of ice-pump events taking place, which determine the ice-ocean interaction at the base of massive floating ice shelves, determining their fate.

No reporting as critical field support has not been provided during austral spring 2022 (in 2022/23).
Variation request to extend the project with view to deploy in austral spring 2023 (in 2023/24) has been approved, however AAS4496 would have needed confirmation to deploy in the April prior (ie April 2023)... hence we requested to defer to spring 2024 (2024/25).
This clearly demonstrates the critical need for planning certainty, as raised before.

The Antarctic sea ice plays a crucial role in the Antarctic climate system and ecosystem, and is closely linked to under shelf ice-ocean processes. We propose an airborne electromagnetic (AEM) survey of pack-ice and fast-ice thickness in the Prydz Bay based out of Davis Station to observe the regional sea-ice characteristics, and to quantify the amount of ice exported from small polynyas along the coast. Such a survey is crucial in light of dramatic changes in the high latitudes with direct effect on ocean-ice-atmosphere dynamic and thermodynamic processes. In addition, we seek to detect the presence (and thickness) of any platelet layer under the fast ice. While there have been few direct observations of platelet ice off East Antarctica, its detection would reveal the presence of previously unmapped supercooled water originating from the bottom melt of ice shelves. In addition, recent verification of data streams similar to the one we propose to collect in this project, has shown, that the observations will provide information on the presence and extent of meltponds on the sea ice. Combining this with satellite-borne laser data will enable large-scale assessments for meltpond occurrence.