Shallow firn cores 1989–2019 in southwest Greenland's percolation zone reveal decreasing density and ice layer thickness after 2012
Abstract Refreezing of meltwater in firn is a major component of Greenland ice-sheet's mass budget, but in situ observations are rare. Here, we compare the firn density and total ice layer thickness in the upper 15 m of 19 new and 27 previously published firn cores drilled at 15 locations in so...
Published in: | Journal of Glaciology |
---|---|
Main Authors: | , , , , , , , , , , , , |
Other Authors: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
2021
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1017/jog.2021.102 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021001027 |
id |
crcambridgeupr:10.1017/jog.2021.102 |
---|---|
record_format |
openpolar |
spelling |
crcambridgeupr:10.1017/jog.2021.102 2024-09-30T14:35:43+00:00 Shallow firn cores 1989–2019 in southwest Greenland's percolation zone reveal decreasing density and ice layer thickness after 2012 Rennermalm, Åsa K. Hock, Regine Covi, Federico Xiao, Jing Corti, Giovanni Kingslake, Jonathan Leidman, Sasha Z. Miège, Clément Macferrin, Michael Machguth, Horst Osterberg, Erich Kameda, Takao McConnell, Joseph R. United States National Science Foundation United States National Science Foundation United States National Science Foundation 2021 http://dx.doi.org/10.1017/jog.2021.102 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021001027 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 68, issue 269, page 431-442 ISSN 0022-1430 1727-5652 journal-article 2021 crcambridgeupr https://doi.org/10.1017/jog.2021.102 2024-09-04T04:03:35Z Abstract Refreezing of meltwater in firn is a major component of Greenland ice-sheet's mass budget, but in situ observations are rare. Here, we compare the firn density and total ice layer thickness in the upper 15 m of 19 new and 27 previously published firn cores drilled at 15 locations in southwest Greenland (1850–2360 m a.s.l.) between 1989 and 2019. At all sites, ice layer thickness covaries with density over time and space. At the two sites with the earliest observations (1989 and 1998), bulk density increased by 15–18%, in the top 15 m over 28 and 21 years, respectively. However, following the extreme melt in 2012, elevation-detrended density using 30 cores from all sites decreased by 15 kg m −3 a −1 in the top 3.75 m between 2013 and 2019. In contrast, the lowest elevation site's density shows no trend. Thus, temporary build-up in firn pore space and meltwater infiltration capacity is possible despite the long-term increase in Greenland ice-sheet melting. Article in Journal/Newspaper Greenland Ice Sheet Journal of Glaciology Cambridge University Press Greenland Journal of Glaciology 1 12 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
Abstract Refreezing of meltwater in firn is a major component of Greenland ice-sheet's mass budget, but in situ observations are rare. Here, we compare the firn density and total ice layer thickness in the upper 15 m of 19 new and 27 previously published firn cores drilled at 15 locations in southwest Greenland (1850–2360 m a.s.l.) between 1989 and 2019. At all sites, ice layer thickness covaries with density over time and space. At the two sites with the earliest observations (1989 and 1998), bulk density increased by 15–18%, in the top 15 m over 28 and 21 years, respectively. However, following the extreme melt in 2012, elevation-detrended density using 30 cores from all sites decreased by 15 kg m −3 a −1 in the top 3.75 m between 2013 and 2019. In contrast, the lowest elevation site's density shows no trend. Thus, temporary build-up in firn pore space and meltwater infiltration capacity is possible despite the long-term increase in Greenland ice-sheet melting. |
author2 |
United States National Science Foundation United States National Science Foundation United States National Science Foundation |
format |
Article in Journal/Newspaper |
author |
Rennermalm, Åsa K. Hock, Regine Covi, Federico Xiao, Jing Corti, Giovanni Kingslake, Jonathan Leidman, Sasha Z. Miège, Clément Macferrin, Michael Machguth, Horst Osterberg, Erich Kameda, Takao McConnell, Joseph R. |
spellingShingle |
Rennermalm, Åsa K. Hock, Regine Covi, Federico Xiao, Jing Corti, Giovanni Kingslake, Jonathan Leidman, Sasha Z. Miège, Clément Macferrin, Michael Machguth, Horst Osterberg, Erich Kameda, Takao McConnell, Joseph R. Shallow firn cores 1989–2019 in southwest Greenland's percolation zone reveal decreasing density and ice layer thickness after 2012 |
author_facet |
Rennermalm, Åsa K. Hock, Regine Covi, Federico Xiao, Jing Corti, Giovanni Kingslake, Jonathan Leidman, Sasha Z. Miège, Clément Macferrin, Michael Machguth, Horst Osterberg, Erich Kameda, Takao McConnell, Joseph R. |
author_sort |
Rennermalm, Åsa K. |
title |
Shallow firn cores 1989–2019 in southwest Greenland's percolation zone reveal decreasing density and ice layer thickness after 2012 |
title_short |
Shallow firn cores 1989–2019 in southwest Greenland's percolation zone reveal decreasing density and ice layer thickness after 2012 |
title_full |
Shallow firn cores 1989–2019 in southwest Greenland's percolation zone reveal decreasing density and ice layer thickness after 2012 |
title_fullStr |
Shallow firn cores 1989–2019 in southwest Greenland's percolation zone reveal decreasing density and ice layer thickness after 2012 |
title_full_unstemmed |
Shallow firn cores 1989–2019 in southwest Greenland's percolation zone reveal decreasing density and ice layer thickness after 2012 |
title_sort |
shallow firn cores 1989–2019 in southwest greenland's percolation zone reveal decreasing density and ice layer thickness after 2012 |
publisher |
Cambridge University Press (CUP) |
publishDate |
2021 |
url |
http://dx.doi.org/10.1017/jog.2021.102 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021001027 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet Journal of Glaciology |
genre_facet |
Greenland Ice Sheet Journal of Glaciology |
op_source |
Journal of Glaciology volume 68, issue 269, page 431-442 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2021.102 |
container_title |
Journal of Glaciology |
container_start_page |
1 |
op_container_end_page |
12 |
_version_ |
1811638972800040960 |