Ice Shelf Damage Characterization and Monitoring around Antarctica

Introduction

The ice shelves of Antarctica act as giant dams limiting ice flow from the interior into the ocean. Recently, several of these dams have shown dramatic signs of damage. Once the ice is fracturing, the dam is weakened, allowing the ice to flow faster and increasing mass loss from the interior of the ice sheet, which results in an accelerated contribution to sea-level.

Importance of the Project

As Antarctica is the largest reservoir of fresh water, correctly predicting its evolution is crucial to anticipate when and how much sea-level will rise. Damage is currently absent from projections of Antarctica's evolution due to:

1. The difficulty of representing this process in numerical models.
2. The lack of observation to constrain them.

Project Aim

The aim of the IceDaM project is to quantify and understand the evolution of damage on ice shelves around Antarctica. My team and I will first use a novel approach based on deep learning to automatically identify the evolution of fractures and their characteristics on satellite imagery.

Methodology

By combining this record with inversions from a high-order ice flow model, we will quantify the links between fractures and changes in ice rigidity, which controls the strength of ice shelves.

Key Variables

To better understand the damage variability, we will measure the evolution of key variables that positively impact the rheological weakening of ice shelves. These time series will be analyzed in a unique fashion to determine the major processes that led to the evolution of damage in the satellite observation era.

Future Developments

Based on these results, we will set up the first “sentinel” of ice shelves by systematically mapping the evolution of fractures in near real time. This will be used to establish new vulnerability indices based on changes in ice rigidity and their impact on glacier mass balance.

Conclusion

This project will open a new window on the processes affecting ice shelves at an unprecedented level of resolution, ultimately allowing us to improve our ability to predict the fate of sea level rise.