Snow Densification and Recent Accumulation Along the iSTAR Traverse, Pine Island Glacier, Antarctica
Neutron probe measurements of snow density from 22 sites in the Pine Island Glacier basin have been used to determine mean annual accumulation using an automatic annual layer identification routine. A mean density profile which can be used to convert radar two-way travel times to depth has been deri...
Published in: | Journal of Geophysical Research: Earth Surface |
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Language: | English |
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Wiley-Blackwell
2017
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Online Access: | https://nrl.northumbria.ac.uk/id/eprint/34495/ https://doi.org/10.1002/2017JF004357 https://nrl.northumbria.ac.uk/id/eprint/34495/1/Morris%20et%20al%20-%20Snow%20Densification%20and%20Recent%20Accumulation%20Along%20the%20iSTAR%20Traverse%20OA.pdf |
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ftunivnorthumb:oai:nrl.northumbria.ac.uk:34495 2023-05-15T13:56:54+02:00 Snow Densification and Recent Accumulation Along the iSTAR Traverse, Pine Island Glacier, Antarctica Morris, E. M. Mulvaney, Robert Arthern, Robert Davies, David Gurney, R. J. Lambert, P. de Rydt, Jan Smith, Annabel Tuckwell, R. J. Winstrup, M. 2017-12 text https://nrl.northumbria.ac.uk/id/eprint/34495/ https://doi.org/10.1002/2017JF004357 https://nrl.northumbria.ac.uk/id/eprint/34495/1/Morris%20et%20al%20-%20Snow%20Densification%20and%20Recent%20Accumulation%20Along%20the%20iSTAR%20Traverse%20OA.pdf en eng Wiley-Blackwell https://nrl.northumbria.ac.uk/id/eprint/34495/1/Morris%20et%20al%20-%20Snow%20Densification%20and%20Recent%20Accumulation%20Along%20the%20iSTAR%20Traverse%20OA.pdf Morris, E. M., Mulvaney, Robert, Arthern, Robert, Davies, David, Gurney, R. J., Lambert, P., de Rydt, Jan, Smith, Annabel, Tuckwell, R. J. and Winstrup, M. (2017) Snow Densification and Recent Accumulation Along the iSTAR Traverse, Pine Island Glacier, Antarctica. Journal of Geophysical Research: Earth Surface, 122 (12). pp. 2284-2301. ISSN 2169-9003 cc_by_4_0 CC-BY F800 Physical and Terrestrial Geographical and Environmental Sciences Article PeerReviewed 2017 ftunivnorthumb https://doi.org/10.1002/2017JF004357 2022-09-25T06:07:21Z Neutron probe measurements of snow density from 22 sites in the Pine Island Glacier basin have been used to determine mean annual accumulation using an automatic annual layer identification routine. A mean density profile which can be used to convert radar two-way travel times to depth has been derived, and the effect of annual fluctuations in density on estimates of the depth of radar reflectors is shown to be insignificant, except very near the surface. Vertical densification rates have been derived from the neutron probe density profiles and from deeper firn core density profiles available at 9 of the sites. These rates are consistent with the rates predicted by the Herron and Langway model for stage 1 densification (by grain-boundary sliding, grain growth and intracrystalline deformation) and stage 2 densification (predominantly by sintering), except in a transition zone extending from ≈8 to ≈13 m from the surface in which 10–14% of the compaction occurs. Profiles of volumetric strain rate at each site show that in this transition zone the rates are consistent with the Arthern densification model. Comparison of the vertical densification rates and volumetric strain rates indicates that the expected relation to mean annual accumulation breaks down at high accumulation rates even when corrections are made for horizontal ice velocity divergence. Article in Journal/Newspaper Antarc* Antarctica Antarctica Journal Pine Island Pine Island Glacier Northumbria University, Newcastle: Northumbria Research Link (NRL) Langway ENVELOPE(-139.783,-139.783,-75.483,-75.483) Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) Journal of Geophysical Research: Earth Surface 122 12 2284 2301 |
institution |
Open Polar |
collection |
Northumbria University, Newcastle: Northumbria Research Link (NRL) |
op_collection_id |
ftunivnorthumb |
language |
English |
topic |
F800 Physical and Terrestrial Geographical and Environmental Sciences |
spellingShingle |
F800 Physical and Terrestrial Geographical and Environmental Sciences Morris, E. M. Mulvaney, Robert Arthern, Robert Davies, David Gurney, R. J. Lambert, P. de Rydt, Jan Smith, Annabel Tuckwell, R. J. Winstrup, M. Snow Densification and Recent Accumulation Along the iSTAR Traverse, Pine Island Glacier, Antarctica |
topic_facet |
F800 Physical and Terrestrial Geographical and Environmental Sciences |
description |
Neutron probe measurements of snow density from 22 sites in the Pine Island Glacier basin have been used to determine mean annual accumulation using an automatic annual layer identification routine. A mean density profile which can be used to convert radar two-way travel times to depth has been derived, and the effect of annual fluctuations in density on estimates of the depth of radar reflectors is shown to be insignificant, except very near the surface. Vertical densification rates have been derived from the neutron probe density profiles and from deeper firn core density profiles available at 9 of the sites. These rates are consistent with the rates predicted by the Herron and Langway model for stage 1 densification (by grain-boundary sliding, grain growth and intracrystalline deformation) and stage 2 densification (predominantly by sintering), except in a transition zone extending from ≈8 to ≈13 m from the surface in which 10–14% of the compaction occurs. Profiles of volumetric strain rate at each site show that in this transition zone the rates are consistent with the Arthern densification model. Comparison of the vertical densification rates and volumetric strain rates indicates that the expected relation to mean annual accumulation breaks down at high accumulation rates even when corrections are made for horizontal ice velocity divergence. |
format |
Article in Journal/Newspaper |
author |
Morris, E. M. Mulvaney, Robert Arthern, Robert Davies, David Gurney, R. J. Lambert, P. de Rydt, Jan Smith, Annabel Tuckwell, R. J. Winstrup, M. |
author_facet |
Morris, E. M. Mulvaney, Robert Arthern, Robert Davies, David Gurney, R. J. Lambert, P. de Rydt, Jan Smith, Annabel Tuckwell, R. J. Winstrup, M. |
author_sort |
Morris, E. M. |
title |
Snow Densification and Recent Accumulation Along the iSTAR Traverse, Pine Island Glacier, Antarctica |
title_short |
Snow Densification and Recent Accumulation Along the iSTAR Traverse, Pine Island Glacier, Antarctica |
title_full |
Snow Densification and Recent Accumulation Along the iSTAR Traverse, Pine Island Glacier, Antarctica |
title_fullStr |
Snow Densification and Recent Accumulation Along the iSTAR Traverse, Pine Island Glacier, Antarctica |
title_full_unstemmed |
Snow Densification and Recent Accumulation Along the iSTAR Traverse, Pine Island Glacier, Antarctica |
title_sort |
snow densification and recent accumulation along the istar traverse, pine island glacier, antarctica |
publisher |
Wiley-Blackwell |
publishDate |
2017 |
url |
https://nrl.northumbria.ac.uk/id/eprint/34495/ https://doi.org/10.1002/2017JF004357 https://nrl.northumbria.ac.uk/id/eprint/34495/1/Morris%20et%20al%20-%20Snow%20Densification%20and%20Recent%20Accumulation%20Along%20the%20iSTAR%20Traverse%20OA.pdf |
long_lat |
ENVELOPE(-139.783,-139.783,-75.483,-75.483) ENVELOPE(-101.000,-101.000,-75.000,-75.000) |
geographic |
Langway Pine Island Glacier |
geographic_facet |
Langway Pine Island Glacier |
genre |
Antarc* Antarctica Antarctica Journal Pine Island Pine Island Glacier |
genre_facet |
Antarc* Antarctica Antarctica Journal Pine Island Pine Island Glacier |
op_relation |
https://nrl.northumbria.ac.uk/id/eprint/34495/1/Morris%20et%20al%20-%20Snow%20Densification%20and%20Recent%20Accumulation%20Along%20the%20iSTAR%20Traverse%20OA.pdf Morris, E. M., Mulvaney, Robert, Arthern, Robert, Davies, David, Gurney, R. J., Lambert, P., de Rydt, Jan, Smith, Annabel, Tuckwell, R. J. and Winstrup, M. (2017) Snow Densification and Recent Accumulation Along the iSTAR Traverse, Pine Island Glacier, Antarctica. Journal of Geophysical Research: Earth Surface, 122 (12). pp. 2284-2301. ISSN 2169-9003 |
op_rights |
cc_by_4_0 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1002/2017JF004357 |
container_title |
Journal of Geophysical Research: Earth Surface |
container_volume |
122 |
container_issue |
12 |
container_start_page |
2284 |
op_container_end_page |
2301 |
_version_ |
1766264492766789632 |