Articles | Volume 17, issue 9
Research article
 | Highlight paper
26 Sep 2023
Research article | Highlight paper |  | 26 Sep 2023

Modes of Antarctic tidal grounding line migration revealed by Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) laser altimetry

Bryony I. D. Freer, Oliver J. Marsh, Anna E. Hogg, Helen Amanda Fricker, and Laurie Padman

Data sets

ATLAS/ICESat-2 L3A Land Ice Height, Version 5 B. Smith, H. A. Fricker, A. Gardner, M. R. Siegfried, S. Adusumilli, B. M. Csathó, N. Holschuh, J. Nilsson, F. S. Paolo, and 60 the ICESat-2 Science Team

ICESat-2 L3 Grounding Zone for Antarctic Ice Shelves, Version 1 T. Li, G. J. Dawson, S. J. Chuter, and J. L. Bamber

MEaSUREs Antarctic Grounding Line from Differential Satellite Radar In- 95 terferometry, Version 2 E. Rignot, J. Mouginot, and B. Scheuchl

High-resolution Image-derived 1Grounding and Hydrostatic Lines for the Antarctic Ice Sheet R. Bindschadler and H. Choi

ICESat-Derived Grounding Zone for Antarctic Ice Shelves K. M. Brunt, H. A. Fricker, L. Padman, and S. O’Neel

Model code and software

Tidal grounding line migration with ICESat-2 Bryony Freer

This paper is worthy of a highlight. The authors show the importance of a process that has been known to exist but hasn’t been measured in this detail before. From a public interest perspective, the results might be tricky to explain in general terms, but the key results fit within the category of “major discovery” and/or “mystery”.
Short summary
We develop a method using ICESat-2 data to measure how Antarctic grounding lines (GLs) migrate across the tide cycle. At an ice plain on the Ronne Ice Shelf we observe 15 km of tidal GL migration, the largest reported distance in Antarctica, dominating any signal of long-term migration. We identify four distinct migration modes, which provide both observational support for models of tidal ice flexure and GL migration and insights into ice shelf–ocean–subglacial interactions in grounding zones.