Ocean Variability Beneath the Filchner-Ronne Ice Shelf Inferred From Basal Melt Rate Time Series
Fourteen phase-sensitive radars (ApRES) were deployed on the Filchner-Ronne Ice Shelf (FRIS) to measure variability in its basal melt rate. Melt rates from sites along the Ronne Depression vary seasonally, consistent with the dynamics of the propagation of seasonal dense water from the western ice f...
Published in: | Journal of Geophysical Research: Oceans |
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Online Access: | http://www.osti.gov/servlets/purl/1891845 https://www.osti.gov/biblio/1891845 https://doi.org/10.1029/2022jc018879 |
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ftosti:oai:osti.gov:1891845 2023-07-30T04:02:41+02:00 Ocean Variability Beneath the Filchner-Ronne Ice Shelf Inferred From Basal Melt Rate Time Series Vaňková, Irena Nicholls, Keith W. 2022-11-11 application/pdf http://www.osti.gov/servlets/purl/1891845 https://www.osti.gov/biblio/1891845 https://doi.org/10.1029/2022jc018879 unknown http://www.osti.gov/servlets/purl/1891845 https://www.osti.gov/biblio/1891845 https://doi.org/10.1029/2022jc018879 doi:10.1029/2022jc018879 54 ENVIRONMENTAL SCIENCES 2022 ftosti https://doi.org/10.1029/2022jc018879 2023-07-11T10:15:26Z Fourteen phase-sensitive radars (ApRES) were deployed on the Filchner-Ronne Ice Shelf (FRIS) to measure variability in its basal melt rate. Melt rates from sites along the Ronne Depression vary seasonally, consistent with the dynamics of the propagation of seasonal dense water from the western ice front into the cavity. Several sites at the back of the FRIS cavity feature a signal with two seasonal maxima. Sub-ice shelf oceanographic data available from one of the sites indicate that this signal is caused by two different pathways followed by the same source water. Inter-annual variability is strongest along a direct flow pathway between western Ronne Ice Front and western Berkner Island. Highest melting occurred in 1999 and 2018, following anomalously low summer sea-ice concentrations in front of the ice shelf. Inter-annual melt rate variability at the back of the FRIS cavity is limited. If present, it is expressed as a suppression or delay in the arrival of the seasonal melt rate minimum, which can be understood in terms of inter-annual stratification changes and variable inflow pathways toward the sites. Long term mean ApRES melt rates agree with estimates from satellite data over eastern FRIS. However, the satellite estimates overstate the area of active basal freezing in the western part of the ice shelf. Furthermore, the temporal melt rate variability from the satellite estimates exaggerates the range of variability at both seasonal and inter-annual time scales with any correspondence between the in-situ and remotely derived inter-annual variability being limited to a single site. Other/Unknown Material Berkner Island Filchner Ronne Ice Shelf Filchner-Ronne Ice Shelf Ice Shelf Ronne Ice Shelf Sea ice SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Ronne Ice Shelf ENVELOPE(-61.000,-61.000,-78.500,-78.500) Berkner Island ENVELOPE(-48.117,-48.117,-79.333,-79.333) Ronne Ice Front ENVELOPE(-55.000,-55.000,-76.000,-76.000) Journal of Geophysical Research: Oceans 127 10 |
institution |
Open Polar |
collection |
SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
op_collection_id |
ftosti |
language |
unknown |
topic |
54 ENVIRONMENTAL SCIENCES |
spellingShingle |
54 ENVIRONMENTAL SCIENCES Vaňková, Irena Nicholls, Keith W. Ocean Variability Beneath the Filchner-Ronne Ice Shelf Inferred From Basal Melt Rate Time Series |
topic_facet |
54 ENVIRONMENTAL SCIENCES |
description |
Fourteen phase-sensitive radars (ApRES) were deployed on the Filchner-Ronne Ice Shelf (FRIS) to measure variability in its basal melt rate. Melt rates from sites along the Ronne Depression vary seasonally, consistent with the dynamics of the propagation of seasonal dense water from the western ice front into the cavity. Several sites at the back of the FRIS cavity feature a signal with two seasonal maxima. Sub-ice shelf oceanographic data available from one of the sites indicate that this signal is caused by two different pathways followed by the same source water. Inter-annual variability is strongest along a direct flow pathway between western Ronne Ice Front and western Berkner Island. Highest melting occurred in 1999 and 2018, following anomalously low summer sea-ice concentrations in front of the ice shelf. Inter-annual melt rate variability at the back of the FRIS cavity is limited. If present, it is expressed as a suppression or delay in the arrival of the seasonal melt rate minimum, which can be understood in terms of inter-annual stratification changes and variable inflow pathways toward the sites. Long term mean ApRES melt rates agree with estimates from satellite data over eastern FRIS. However, the satellite estimates overstate the area of active basal freezing in the western part of the ice shelf. Furthermore, the temporal melt rate variability from the satellite estimates exaggerates the range of variability at both seasonal and inter-annual time scales with any correspondence between the in-situ and remotely derived inter-annual variability being limited to a single site. |
author |
Vaňková, Irena Nicholls, Keith W. |
author_facet |
Vaňková, Irena Nicholls, Keith W. |
author_sort |
Vaňková, Irena |
title |
Ocean Variability Beneath the Filchner-Ronne Ice Shelf Inferred From Basal Melt Rate Time Series |
title_short |
Ocean Variability Beneath the Filchner-Ronne Ice Shelf Inferred From Basal Melt Rate Time Series |
title_full |
Ocean Variability Beneath the Filchner-Ronne Ice Shelf Inferred From Basal Melt Rate Time Series |
title_fullStr |
Ocean Variability Beneath the Filchner-Ronne Ice Shelf Inferred From Basal Melt Rate Time Series |
title_full_unstemmed |
Ocean Variability Beneath the Filchner-Ronne Ice Shelf Inferred From Basal Melt Rate Time Series |
title_sort |
ocean variability beneath the filchner-ronne ice shelf inferred from basal melt rate time series |
publishDate |
2022 |
url |
http://www.osti.gov/servlets/purl/1891845 https://www.osti.gov/biblio/1891845 https://doi.org/10.1029/2022jc018879 |
long_lat |
ENVELOPE(-61.000,-61.000,-78.500,-78.500) ENVELOPE(-48.117,-48.117,-79.333,-79.333) ENVELOPE(-55.000,-55.000,-76.000,-76.000) |
geographic |
Ronne Ice Shelf Berkner Island Ronne Ice Front |
geographic_facet |
Ronne Ice Shelf Berkner Island Ronne Ice Front |
genre |
Berkner Island Filchner Ronne Ice Shelf Filchner-Ronne Ice Shelf Ice Shelf Ronne Ice Shelf Sea ice |
genre_facet |
Berkner Island Filchner Ronne Ice Shelf Filchner-Ronne Ice Shelf Ice Shelf Ronne Ice Shelf Sea ice |
op_relation |
http://www.osti.gov/servlets/purl/1891845 https://www.osti.gov/biblio/1891845 https://doi.org/10.1029/2022jc018879 doi:10.1029/2022jc018879 |
op_doi |
https://doi.org/10.1029/2022jc018879 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
127 |
container_issue |
10 |
_version_ |
1772813516228526080 |