The distribution and evolution of surface fractures on pan-Antarctic ice shelves

Abstract

Surface fractures have a great impact on ice shelf stability in Antarctica and can be considered precursors of ice shelf calving. However, our understanding of the spatial distribution and temporal evolution of surface fractures on the Antarctic ice shelf is limited. In this study, a ResUNet model was implemented on the Moderate Resolution Imaging Spectroradiometer (MODIS)-based Mosaic of Antarctica (MOA) to identify the spatial distribution of Antarctic ice shelf surface fractures in 2004, 2009, and 2014. The accuracy of identification had an F1 value of 0.771. Our model identified 44744.59$\; \pm \;$2619.61 km² of surface fractures in 2004, 43737.15$\; \pm \;$2644.60 km² in 2009, and 42978.67 $\pm \;$2639.33 km² in 2014. The reduction is primarily attributed to the variation in surface fractures within 20 km of the ice front, paratactically in the Amundsen and Wilkes sectors. Ice shelves in the Amundsen sector typically have a widespread distribution of surface fractures, with particularly high concentrations found in the Thwaites Ice Shelf, Crosson Ice Shelf and Getz Ice Shelf. The Brunt Ice Shelf also exhibits numerous surface fractures. This study provides comprehensive and detailed information about surface fractures on Antarctic ice shelves, carrying implications for evaluating ice shelf vulnerability.

Keywords

• surface fractures
• antarctic ice shelf
• resunet
• moa