Ocean Coupling Limits Rupture Velocity of Fastest Observed Ice Shelf Rift Propagation Event
Abstract The Antarctic ice sheet is buttressed by floating ice shelves that calve icebergs along large fractures called rifts. Despite the significant influence exerted by rifting on ice shelf geometry and buttressing, the scarcity of in situ observations of rift propagation contributes considerable...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2024-02-01
|
| Series: | AGU Advances |
| Subjects: | |
| Online Access: | https://doi.org/10.1029/2023AV001023 |
| _version_ | 1797294715119337472 |
|---|---|
| author | Stephanie D. Olinger Bradley P. Lipovsky Marine A. Denolle |
| author_facet | Stephanie D. Olinger Bradley P. Lipovsky Marine A. Denolle |
| author_sort | Stephanie D. Olinger |
| collection | DOAJ |
| description | Abstract The Antarctic ice sheet is buttressed by floating ice shelves that calve icebergs along large fractures called rifts. Despite the significant influence exerted by rifting on ice shelf geometry and buttressing, the scarcity of in situ observations of rift propagation contributes considerable uncertainty to understanding rift dynamics. Here, we report the first‐ever seismic recording of a multiple‐kilometer rift propagation event. Remote sensing and seismic recordings reveal that a rift in the Pine Island Glacier Ice Shelf extended 10.53 km at a speed of 35.1 m/s, the fastest known ice fracture at this scale. We simulate ocean‐coupled rift propagation and find that the dynamics of water flow within the rift limit the propagation rate, resulting in rupture two orders of magnitude slower than typically predicted for brittle fracture. Using seismic recordings of the elastic waves generated during rift propagation, we estimate that ocean water flows into the rift at a rate of at least 2,300 m3/s during rift propagation and causes mixing in the subshelf cavity. Our observations support the hypotheses that large ice shelf rift propagation events are brittle, hydrodynamically limited, and exhibit sensitive coupling with the surrounding ocean. |
| first_indexed | 2024-03-07T21:35:12Z |
| format | Article |
| id | doaj.art-fd13d334cb9e4b3eb5311c62eaf85c59 |
| institution | Directory Open Access Journal |
| issn | 2576-604X |
| language | English |
| last_indexed | 2024-03-07T21:35:12Z |
| publishDate | 2024-02-01 |
| publisher | Wiley |
| record_format | Article |
| series | AGU Advances |
| spelling | doaj.art-fd13d334cb9e4b3eb5311c62eaf85c592024-02-26T14:22:31ZengWileyAGU Advances2576-604X2024-02-0151n/an/a10.1029/2023AV001023Ocean Coupling Limits Rupture Velocity of Fastest Observed Ice Shelf Rift Propagation EventStephanie D. Olinger0Bradley P. Lipovsky1Marine A. Denolle2Department of Earth and Planetary Sciences Harvard University Cambridge MA USADepartment of Earth and Space Sciences University of Washington Seattle WA USADepartment of Earth and Space Sciences University of Washington Seattle WA USAAbstract The Antarctic ice sheet is buttressed by floating ice shelves that calve icebergs along large fractures called rifts. Despite the significant influence exerted by rifting on ice shelf geometry and buttressing, the scarcity of in situ observations of rift propagation contributes considerable uncertainty to understanding rift dynamics. Here, we report the first‐ever seismic recording of a multiple‐kilometer rift propagation event. Remote sensing and seismic recordings reveal that a rift in the Pine Island Glacier Ice Shelf extended 10.53 km at a speed of 35.1 m/s, the fastest known ice fracture at this scale. We simulate ocean‐coupled rift propagation and find that the dynamics of water flow within the rift limit the propagation rate, resulting in rupture two orders of magnitude slower than typically predicted for brittle fracture. Using seismic recordings of the elastic waves generated during rift propagation, we estimate that ocean water flows into the rift at a rate of at least 2,300 m3/s during rift propagation and causes mixing in the subshelf cavity. Our observations support the hypotheses that large ice shelf rift propagation events are brittle, hydrodynamically limited, and exhibit sensitive coupling with the surrounding ocean.https://doi.org/10.1029/2023AV001023ice shelf riftingiceberg calvingAntarcticaPine Island Glaciermixingfracture |
| spellingShingle | Stephanie D. Olinger Bradley P. Lipovsky Marine A. Denolle Ocean Coupling Limits Rupture Velocity of Fastest Observed Ice Shelf Rift Propagation Event AGU Advances ice shelf rifting iceberg calving Antarctica Pine Island Glacier mixing fracture |
| title | Ocean Coupling Limits Rupture Velocity of Fastest Observed Ice Shelf Rift Propagation Event |
| title_full | Ocean Coupling Limits Rupture Velocity of Fastest Observed Ice Shelf Rift Propagation Event |
| title_fullStr | Ocean Coupling Limits Rupture Velocity of Fastest Observed Ice Shelf Rift Propagation Event |
| title_full_unstemmed | Ocean Coupling Limits Rupture Velocity of Fastest Observed Ice Shelf Rift Propagation Event |
| title_short | Ocean Coupling Limits Rupture Velocity of Fastest Observed Ice Shelf Rift Propagation Event |
| title_sort | ocean coupling limits rupture velocity of fastest observed ice shelf rift propagation event |
| topic | ice shelf rifting iceberg calving Antarctica Pine Island Glacier mixing fracture |
| url | https://doi.org/10.1029/2023AV001023 |
| work_keys_str_mv | AT stephaniedolinger oceancouplinglimitsrupturevelocityoffastestobservediceshelfriftpropagationevent AT bradleyplipovsky oceancouplinglimitsrupturevelocityoffastestobservediceshelfriftpropagationevent AT marineadenolle oceancouplinglimitsrupturevelocityoffastestobservediceshelfriftpropagationevent |