Grounding line retreat and tide-modulated ocean channels at Moscow University and Totten Glacier ice shelves, East Antarctica
<p>The Totten and Moscow University glaciers, located in East Antarctica, contain 5.1 m sea-level equivalent of ice and have been losing mass over recent decades. Using ICESat-2 laser altimetry repeat track analysis and satellite radar interferometry from Sentinel-1a/b synthetic aperture radar...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2023-03-01
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| Series: | The Cryosphere |
| Online Access: | https://tc.copernicus.org/articles/17/1003/2023/tc-17-1003-2023.pdf |
| Summary: | <p>The Totten and Moscow University glaciers, located in
East Antarctica, contain 5.1 m sea-level equivalent of ice and have been
losing mass over recent decades. Using ICESat-2 laser altimetry repeat track
analysis and satellite radar interferometry from Sentinel-1a/b synthetic aperture radar (SAR) images,
we mapped the grounding line (GL) locations of these two glaciers between
2017 and 2021. By comparing the 2017–2021 GL measurements with historic
GLs, we detected pervasive GL retreats along the ice plains at the glacier
central trunk of Totten Glacier Ice Shelf (TGIS) and Moscow University Ice
Shelf (MUIS). The GL retreated <span class="inline-formula">3.51±0.49</span> km at TGIS, while it
retreated <span class="inline-formula">13.85±0.08</span> km at MUIS from 1996. Using CryoSat-2 radar
altimetry, we found that the observed GL retreats are coincident with high
thinning rates, in addition to high ice velocities, indicating a mass loss
pattern dominated by ice dynamics. We also identified two tide-modulated
ocean channels on Totten Glacier Eastern Ice Shelf (TGEIS) and Moscow
University Western Ice Shelf (MUWIS), where the ocean channel widths are
highly correlated with the differential tidal amplitudes. The opening of the
MUWIS ocean channel connects the two previously separated TGIS and MUIS
systems, which might open a pathway for the warm modified Circumpolar Deep
Water to enter the main MUIS cavity and facilitate further GL retreat.</p> |
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| ISSN: | 1994-0416 1994-0424 |