Annual cycle in flow of Ross Ice Shelf, Antarctica: contribution of variable basal melting
Ice shelves play a critical role in modulating dynamic loss of ice from the grounded portion of the Antarctic Ice Sheet and its contribution to sea-level rise. Measurements of ice-shelf motion provide insights into processes modifying buttressing. Here we investigate the effect of seasonal variabili...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
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Cambridge University Press
2020-10-01
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| Series: | Journal of Glaciology |
| Subjects: | |
| Online Access: | https://www.cambridge.org/core/product/identifier/S0022143020000611/type/journal_article |
| _version_ | 1811155779267330048 |
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| author | Emilie Klein Cyrille Mosbeux Peter D. Bromirski Laurie Padman Yehuda Bock Scott R. Springer Helen A. Fricker |
| author_facet | Emilie Klein Cyrille Mosbeux Peter D. Bromirski Laurie Padman Yehuda Bock Scott R. Springer Helen A. Fricker |
| author_sort | Emilie Klein |
| collection | DOAJ |
| description | Ice shelves play a critical role in modulating dynamic loss of ice from the grounded portion of the Antarctic Ice Sheet and its contribution to sea-level rise. Measurements of ice-shelf motion provide insights into processes modifying buttressing. Here we investigate the effect of seasonal variability of basal melting on ice flow of Ross Ice Shelf. Velocities were measured from November 2015 to December 2016 at 12 GPS stations deployed from the ice front to 430 km upstream. The flow-parallel velocity anomaly at each station, relative to the annual mean, was small during early austral summer (November–January), negative during February–April, and positive during austral winter (May–September). The maximum velocity anomaly reached several metres per year at most stations. We used a 2-D ice-sheet model of the RIS and its grounded tributaries to explore the seasonal response of the ice sheet to time-varying basal melt rates. We find that melt-rate response to changes in summer upper-ocean heating near the ice front will affect the future flow of RIS and its tributary glaciers. However, modelled seasonal flow variations from increased summer basal melting near the ice front are much smaller than observed, suggesting that other as-yet-unidentified seasonal processes are currently dominant. |
| first_indexed | 2024-04-10T04:40:21Z |
| format | Article |
| id | doaj.art-0ca9e75d194846a3bfdc13ca07bd16cf |
| institution | Directory Open Access Journal |
| issn | 0022-1430 1727-5652 |
| language | English |
| last_indexed | 2024-04-10T04:40:21Z |
| publishDate | 2020-10-01 |
| publisher | Cambridge University Press |
| record_format | Article |
| series | Journal of Glaciology |
| spelling | doaj.art-0ca9e75d194846a3bfdc13ca07bd16cf2023-03-09T12:40:58ZengCambridge University PressJournal of Glaciology0022-14301727-56522020-10-016686187510.1017/jog.2020.61Annual cycle in flow of Ross Ice Shelf, Antarctica: contribution of variable basal meltingEmilie Klein0https://orcid.org/0000-0003-3239-5118Cyrille Mosbeux1Peter D. Bromirski2Laurie Padman3https://orcid.org/0000-0003-2010-642XYehuda Bock4Scott R. Springer5Helen A. Fricker6Scripps Institution of Oceanography, UC San Diego, La Jolla, CA, USA Laboratoire de Géologie, Département de Géosciences, PSL Research University, ENS, CNRS, UMR 8538, Paris, FranceScripps Institution of Oceanography, UC San Diego, La Jolla, CA, USAScripps Institution of Oceanography, UC San Diego, La Jolla, CA, USAEarth and Space Research, Corvallis, OR, USAScripps Institution of Oceanography, UC San Diego, La Jolla, CA, USAEarth and Space Research, Seattle, WA, USAScripps Institution of Oceanography, UC San Diego, La Jolla, CA, USAIce shelves play a critical role in modulating dynamic loss of ice from the grounded portion of the Antarctic Ice Sheet and its contribution to sea-level rise. Measurements of ice-shelf motion provide insights into processes modifying buttressing. Here we investigate the effect of seasonal variability of basal melting on ice flow of Ross Ice Shelf. Velocities were measured from November 2015 to December 2016 at 12 GPS stations deployed from the ice front to 430 km upstream. The flow-parallel velocity anomaly at each station, relative to the annual mean, was small during early austral summer (November–January), negative during February–April, and positive during austral winter (May–September). The maximum velocity anomaly reached several metres per year at most stations. We used a 2-D ice-sheet model of the RIS and its grounded tributaries to explore the seasonal response of the ice sheet to time-varying basal melt rates. We find that melt-rate response to changes in summer upper-ocean heating near the ice front will affect the future flow of RIS and its tributary glaciers. However, modelled seasonal flow variations from increased summer basal melting near the ice front are much smaller than observed, suggesting that other as-yet-unidentified seasonal processes are currently dominant.https://www.cambridge.org/core/product/identifier/S0022143020000611/type/journal_articleAntarctic glaciologyice/ocean interactionsice shelves |
| spellingShingle | Emilie Klein Cyrille Mosbeux Peter D. Bromirski Laurie Padman Yehuda Bock Scott R. Springer Helen A. Fricker Annual cycle in flow of Ross Ice Shelf, Antarctica: contribution of variable basal melting Journal of Glaciology Antarctic glaciology ice/ocean interactions ice shelves |
| title | Annual cycle in flow of Ross Ice Shelf, Antarctica: contribution of variable basal melting |
| title_full | Annual cycle in flow of Ross Ice Shelf, Antarctica: contribution of variable basal melting |
| title_fullStr | Annual cycle in flow of Ross Ice Shelf, Antarctica: contribution of variable basal melting |
| title_full_unstemmed | Annual cycle in flow of Ross Ice Shelf, Antarctica: contribution of variable basal melting |
| title_short | Annual cycle in flow of Ross Ice Shelf, Antarctica: contribution of variable basal melting |
| title_sort | annual cycle in flow of ross ice shelf antarctica contribution of variable basal melting |
| topic | Antarctic glaciology ice/ocean interactions ice shelves |
| url | https://www.cambridge.org/core/product/identifier/S0022143020000611/type/journal_article |
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