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v2.0 of this dataset includes: All surface-elevation change (dh/dt) data from ICESat, CryoSat-2, and ICESat-2 altimetry missions necessary to reproduce figures and analysis from Verboncoeur et al. (2024) ('*dhdt_smb'); a file containing x,y positions of the ad-hoc reference tracks formed around ICESat ground tracks ('xy_is_masked.csv'); a folder containing delineated boundaries used in analysis ('SHAPES.zip'); folders containing raw subsetted ICESat data ('IS_data.zip') and a folder containing CryoCloud scripts for downloading ICESat-2 data ('IS2_processing_cryocloud.zip')
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This content will become publicly available on January 1, 2026
Multi-decadal evolution of Crary Ice Rise region, West Antarctica, amid modern ice-stream deceleration
Abstract The ongoing deceleration of Whillans Ice Stream, West Antarctica, provides an opportunity to investigate the co-evolution of ice-shelf pinning points and ice-stream flux variability. Here, we construct and analyze a 20-year multi-mission satellite altimetry record of dynamic ice surface-elevation change (dh/dt) in the grounded region encompassing lower Whillans Ice Stream and Crary Ice Rise, a major pinning point of Ross Ice Shelf. We developed a new method for generating multi-mission time series that reduces spatial bias and implemented this method with altimetry data from the Ice, Cloud, and land Elevation Satellite (ICESat; 2003–09), CryoSat-2 (2010–present), and ICESat-2 (2018–present) altimetry missions. We then used thedh/dttime series to identify persistent patterns of surface-elevation change and evaluate regional mass balance. Our results suggest a persistent anomalous reduction in ice thickness and effective backstress in the peninsula connecting Whillans Ice Plain to Crary Ice Rise. The multi-decadal observational record of pinning-point mass redistribution and grounding zone retreat presented in this study highlights the on-going reorganization of the southern Ross Ice Shelf embayment buttressing regime in response to ice-stream deceleration.
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- Award ID(s):
- 2049302
- PAR ID:
- 10595999
- Publisher / Repository:
- International Glaciological Society
- Date Published:
- Journal Name:
- Journal of Glaciology
- Volume:
- 71
- ISSN:
- 0022-1430
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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