Characterizing the shape, size and freeboard of sea-ice floes in the Weddell sea from IceSat-2 and Sentinel-2
Abstract
The size and thickness distribution of sea-ice floes play an important role in shaping the overall larger scale behavior of the sea-ice pack. For many years, sparse observations have prevented a detailed characterisation of the three-dimensional geometry of sea-ice floes, particularly over Antarctica. Here, we use a combination of overlapped altimetry (IceSat-2) and imagery (Sentinel-2) products to investigate the evolution of sea-ice floe properties over a seasonal cycle in the Weddell sea. We use along-track lead-detection and freeboard measurements from IceSat-2 to infer floe chord lengths and an associated floe thickness distribution. Characteristic along-track freeboard profiles show that larger floes tend to be thicker than smaller ones, and on average floes are thicker at their center compared to their edges. Concomitant observations from satellite imagery also allows us to characterize the roundness of sea-ice floes, and to link the floe chord distribution to a floe area distribution, obtained from image segmentation. We find that there are significant regional differences in these inferences, and in particular, the Antarctic peninsula undergoes sharp changes in ice thickness distribution during the Spring and Fall seasons, while the rest of the Bay shows statistics that are more consistent throughout the year.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFM.C25B..06G