Recent unpinning and calving front retreat of Pine Island Glacier documented by new bathymetric and satellite data
Pine Island Glacier currently experiences the largest negative ice sheet mass balance in comparison to other outlet glaciers in Antarctica and hence is the largest contributor to modern sea-level rise. Ice loss of this glacial outlet and neighbouring ones has increased greatly over the recent decade...
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ftawi:oai:epic.awi.de:45590 2023-05-15T13:45:21+02:00 Recent unpinning and calving front retreat of Pine Island Glacier documented by new bathymetric and satellite data Arndt, Jan Erik Larter, Robert D. Friedl, Peter Gohl, Karsten Höppner, Kathrin PS104, Shipboard Scientific Party 2017-09-11 https://epic.awi.de/id/eprint/45590/ https://hdl.handle.net/10013/epic.51754 unknown Arndt, J. E. orcid:0000-0002-9413-1612 , Larter, R. D. , Friedl, P. , Gohl, K. orcid:0000-0002-9558-2116 , Höppner, K. and PS104, S. S. P. (2017) Recent unpinning and calving front retreat of Pine Island Glacier documented by new bathymetric and satellite data , Past Antarctic Ice Sheet (PAIS) Conference, Trieste, 11 September 2017 - 15 September 2017 . hdl:10013/epic.51754 EPIC3Past Antarctic Ice Sheet (PAIS) Conference, Trieste, 2017-09-11-2017-09-15 Conference notRev 2017 ftawi 2021-12-24T15:43:20Z Pine Island Glacier currently experiences the largest negative ice sheet mass balance in comparison to other outlet glaciers in Antarctica and hence is the largest contributor to modern sea-level rise. Ice loss of this glacial outlet and neighbouring ones has increased greatly over the recent decades through ice thinning and flow acceleration that also resulted in rapid grounding line retreat, most likely as a result of basal melting induced by the inflow of warm Circumpolar Deep Water onto the shelf. Due to the glacier’s topographic setting, a bed that deepens beyond the grounding line to the deep interior basin of the West Antarctic Ice Sheet (WAIS), it has been suggested that this increased ice loss may be a precursor of WAIS collapse. Despite the increased mass loss, however, the calving front of Pine Island Glacier remained more or less stable in a position west of a pinning point located at the northern part of the glacier and its orientation remained similar (10-30° east of north) since the earliest observations in the mid-20th century. Large icebergs where calved at intervals of a few years, e.g. the B-31 calving event (720 km²) in November 2013, but subsequently the calving front re-advanced close to or even beyond its former position. In 2015 this pattern changed with a calving event initiated by a large rift oriented 55° east of north and the calving front for the first time retreated east of the pinning point. The rifts that initiated this calving event were proposed to have formed by expansion of basal crevasses due to ocean forcing. In 2017 we were able to access the formerly ice-shelf covered area during RV Polarstern expedition PS104. Bathymetric data from this area revealed a bathymetric knoll with minimum water depth of ~375 m that was the former pinning point of the glacier. A new rift 8-9 km upstream of the calving line that may initiate the next calving event within a year was visited by helicopter. Satellite data acquired in the last decades suggest that unpinning from the bathymetric knoll likely took place in 2006. We use these data collected during expedition PS104 in combination with the satellite data to investigate the impact of glacier unpinning on Pine Island Glacier calving dynamics. Conference Object Antarc* Antarctic Antarctica Ice Sheet Ice Shelf Iceberg* Pine Island Pine Island Glacier Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Antarctic Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) West Antarctic Ice Sheet |
institution |
Open Polar |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
Pine Island Glacier currently experiences the largest negative ice sheet mass balance in comparison to other outlet glaciers in Antarctica and hence is the largest contributor to modern sea-level rise. Ice loss of this glacial outlet and neighbouring ones has increased greatly over the recent decades through ice thinning and flow acceleration that also resulted in rapid grounding line retreat, most likely as a result of basal melting induced by the inflow of warm Circumpolar Deep Water onto the shelf. Due to the glacier’s topographic setting, a bed that deepens beyond the grounding line to the deep interior basin of the West Antarctic Ice Sheet (WAIS), it has been suggested that this increased ice loss may be a precursor of WAIS collapse. Despite the increased mass loss, however, the calving front of Pine Island Glacier remained more or less stable in a position west of a pinning point located at the northern part of the glacier and its orientation remained similar (10-30° east of north) since the earliest observations in the mid-20th century. Large icebergs where calved at intervals of a few years, e.g. the B-31 calving event (720 km²) in November 2013, but subsequently the calving front re-advanced close to or even beyond its former position. In 2015 this pattern changed with a calving event initiated by a large rift oriented 55° east of north and the calving front for the first time retreated east of the pinning point. The rifts that initiated this calving event were proposed to have formed by expansion of basal crevasses due to ocean forcing. In 2017 we were able to access the formerly ice-shelf covered area during RV Polarstern expedition PS104. Bathymetric data from this area revealed a bathymetric knoll with minimum water depth of ~375 m that was the former pinning point of the glacier. A new rift 8-9 km upstream of the calving line that may initiate the next calving event within a year was visited by helicopter. Satellite data acquired in the last decades suggest that unpinning from the bathymetric knoll likely took place in 2006. We use these data collected during expedition PS104 in combination with the satellite data to investigate the impact of glacier unpinning on Pine Island Glacier calving dynamics. |
format |
Conference Object |
author |
Arndt, Jan Erik Larter, Robert D. Friedl, Peter Gohl, Karsten Höppner, Kathrin PS104, Shipboard Scientific Party |
spellingShingle |
Arndt, Jan Erik Larter, Robert D. Friedl, Peter Gohl, Karsten Höppner, Kathrin PS104, Shipboard Scientific Party Recent unpinning and calving front retreat of Pine Island Glacier documented by new bathymetric and satellite data |
author_facet |
Arndt, Jan Erik Larter, Robert D. Friedl, Peter Gohl, Karsten Höppner, Kathrin PS104, Shipboard Scientific Party |
author_sort |
Arndt, Jan Erik |
title |
Recent unpinning and calving front retreat of Pine Island Glacier documented by new bathymetric and satellite data |
title_short |
Recent unpinning and calving front retreat of Pine Island Glacier documented by new bathymetric and satellite data |
title_full |
Recent unpinning and calving front retreat of Pine Island Glacier documented by new bathymetric and satellite data |
title_fullStr |
Recent unpinning and calving front retreat of Pine Island Glacier documented by new bathymetric and satellite data |
title_full_unstemmed |
Recent unpinning and calving front retreat of Pine Island Glacier documented by new bathymetric and satellite data |
title_sort |
recent unpinning and calving front retreat of pine island glacier documented by new bathymetric and satellite data |
publishDate |
2017 |
url |
https://epic.awi.de/id/eprint/45590/ https://hdl.handle.net/10013/epic.51754 |
long_lat |
ENVELOPE(-101.000,-101.000,-75.000,-75.000) |
geographic |
Antarctic Pine Island Glacier West Antarctic Ice Sheet |
geographic_facet |
Antarctic Pine Island Glacier West Antarctic Ice Sheet |
genre |
Antarc* Antarctic Antarctica Ice Sheet Ice Shelf Iceberg* Pine Island Pine Island Glacier |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet Ice Shelf Iceberg* Pine Island Pine Island Glacier |
op_source |
EPIC3Past Antarctic Ice Sheet (PAIS) Conference, Trieste, 2017-09-11-2017-09-15 |
op_relation |
Arndt, J. E. orcid:0000-0002-9413-1612 , Larter, R. D. , Friedl, P. , Gohl, K. orcid:0000-0002-9558-2116 , Höppner, K. and PS104, S. S. P. (2017) Recent unpinning and calving front retreat of Pine Island Glacier documented by new bathymetric and satellite data , Past Antarctic Ice Sheet (PAIS) Conference, Trieste, 11 September 2017 - 15 September 2017 . hdl:10013/epic.51754 |
_version_ |
1766220977573724160 |