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

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 & PLUSMN; 2619.61 km(2) of surface fractures in 2004, 43737.15 & PLUSMN; 2644.60 km(2) in 2009, and 42978.67 & PLUSMN; 2639.33 km(2) 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.

Automated summary

In this study, a ResUNet model was used to identify the spatial distribution of surface fractures on Antarctic ice shelves using MODIS data. It was found that the total area of surface fractures decreased from 2004 to 2014, primarily due to changes in fractures within 20 km of the ice front in the Amundsen and Wilkes sectors. High concentrations of fractures were particularly observed in the Thwaites Ice Shelf, Crosson Ice Shelf, and Getz Ice Shelf in the Amundsen sector. This study provides comprehensive and detailed information about surface fractures on Antarctic ice shelves and has implications for evaluating their vulnerability.