Uncertainties in Arctic sea ice thickness and volume: new estimates and implications for trends
International audience Sea ice volume has decreased in the last decades, evoked by changes in sea ice area and thickness. Estimates of sea ice area and thickness rely on a number of geophysical parameters which introduce large uncertainties. To quantify these uncertainties we use freeboard retrieval...
Published in: | The Cryosphere |
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Language: | English |
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Online Access: | https://hal.univ-grenoble-alpes.fr/hal-03405842 https://hal.univ-grenoble-alpes.fr/hal-03405842/document https://hal.univ-grenoble-alpes.fr/hal-03405842/file/Zygmuntowska2014The_Cryosphere.pdf https://doi.org/10.5194/tc-8-705-2014 |
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ftccsdartic:oai:HAL:hal-03405842v1 2023-05-15T14:29:21+02:00 Uncertainties in Arctic sea ice thickness and volume: new estimates and implications for trends Zygmuntowska, M Rampal, P Ivanova, N Smedsrud, L Nansen Environmental and Remote Sensing Center Bergen (NERSC) University of Bergen (UiB) 2014 https://hal.univ-grenoble-alpes.fr/hal-03405842 https://hal.univ-grenoble-alpes.fr/hal-03405842/document https://hal.univ-grenoble-alpes.fr/hal-03405842/file/Zygmuntowska2014The_Cryosphere.pdf https://doi.org/10.5194/tc-8-705-2014 en eng HAL CCSD Copernicus info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-8-705-2014 hal-03405842 https://hal.univ-grenoble-alpes.fr/hal-03405842 https://hal.univ-grenoble-alpes.fr/hal-03405842/document https://hal.univ-grenoble-alpes.fr/hal-03405842/file/Zygmuntowska2014The_Cryosphere.pdf doi:10.5194/tc-8-705-2014 info:eu-repo/semantics/OpenAccess ISSN: 1994-0424 EISSN: 1994-0416 The Cryosphere https://hal.univ-grenoble-alpes.fr/hal-03405842 The Cryosphere, Copernicus 2014, 8 (2), pp.705 - 720. ⟨10.5194/tc-8-705-2014⟩ [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography info:eu-repo/semantics/article Journal articles 2014 ftccsdartic https://doi.org/10.5194/tc-8-705-2014 2021-10-30T22:23:30Z International audience Sea ice volume has decreased in the last decades, evoked by changes in sea ice area and thickness. Estimates of sea ice area and thickness rely on a number of geophysical parameters which introduce large uncertainties. To quantify these uncertainties we use freeboard retrievals from ICESat and investigate different assumptions about snow depth, sea ice density and area. We find that uncertainties in ice area are of minor importance for the estimates of sea ice volume during the cold season in the Arctic basin. The choice of mean ice density used when converting sea ice freeboard into thickness mainly influences the resulting mean sea ice thickness, while snow depth on top of the ice is the main driver for the year-to-year variability, particularly in late winter. The absolute uncertainty in the mean sea ice thickness is 0.28 m in February/March and 0.21 m in October/November. The uncertainty in snow depth contributes up to 70 % of the total uncertainty and the ice density 30-35 %, with higher values in October/November. We find large uncertainties in the total sea ice volume and trend. The mean total sea ice volume is 10 120±1280 km 3 in October/November and 13 250 ± 1860 km 3 in February/March for the time period 2005-2007. Based on these uncertainties we obtain trends in sea ice volume of 1450 ± 530 km 3 a 1 in October/November and 880 ± 260 km 3 a 1 in February/March over the ICESat period (2003-2008). Our results indicate that, taking into account the uncertainties, the decline in sea ice volume in the Arctic between the ICESat (2003-2008) and CryoSat-2 (2010-2012) periods may have been less dramatic than reported in previous studies. However, more work and validation is required to quantify these changes and analyse possible unresolved biases in the freeboard retrievals. Article in Journal/Newspaper Arctic Basin Arctic Sea ice The Cryosphere Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) Arctic The Cryosphere 8 2 705 720 |
institution |
Open Polar |
collection |
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) |
op_collection_id |
ftccsdartic |
language |
English |
topic |
[SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
spellingShingle |
[SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography Zygmuntowska, M Rampal, P Ivanova, N Smedsrud, L Uncertainties in Arctic sea ice thickness and volume: new estimates and implications for trends |
topic_facet |
[SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
description |
International audience Sea ice volume has decreased in the last decades, evoked by changes in sea ice area and thickness. Estimates of sea ice area and thickness rely on a number of geophysical parameters which introduce large uncertainties. To quantify these uncertainties we use freeboard retrievals from ICESat and investigate different assumptions about snow depth, sea ice density and area. We find that uncertainties in ice area are of minor importance for the estimates of sea ice volume during the cold season in the Arctic basin. The choice of mean ice density used when converting sea ice freeboard into thickness mainly influences the resulting mean sea ice thickness, while snow depth on top of the ice is the main driver for the year-to-year variability, particularly in late winter. The absolute uncertainty in the mean sea ice thickness is 0.28 m in February/March and 0.21 m in October/November. The uncertainty in snow depth contributes up to 70 % of the total uncertainty and the ice density 30-35 %, with higher values in October/November. We find large uncertainties in the total sea ice volume and trend. The mean total sea ice volume is 10 120±1280 km 3 in October/November and 13 250 ± 1860 km 3 in February/March for the time period 2005-2007. Based on these uncertainties we obtain trends in sea ice volume of 1450 ± 530 km 3 a 1 in October/November and 880 ± 260 km 3 a 1 in February/March over the ICESat period (2003-2008). Our results indicate that, taking into account the uncertainties, the decline in sea ice volume in the Arctic between the ICESat (2003-2008) and CryoSat-2 (2010-2012) periods may have been less dramatic than reported in previous studies. However, more work and validation is required to quantify these changes and analyse possible unresolved biases in the freeboard retrievals. |
author2 |
Nansen Environmental and Remote Sensing Center Bergen (NERSC) University of Bergen (UiB) |
format |
Article in Journal/Newspaper |
author |
Zygmuntowska, M Rampal, P Ivanova, N Smedsrud, L |
author_facet |
Zygmuntowska, M Rampal, P Ivanova, N Smedsrud, L |
author_sort |
Zygmuntowska, M |
title |
Uncertainties in Arctic sea ice thickness and volume: new estimates and implications for trends |
title_short |
Uncertainties in Arctic sea ice thickness and volume: new estimates and implications for trends |
title_full |
Uncertainties in Arctic sea ice thickness and volume: new estimates and implications for trends |
title_fullStr |
Uncertainties in Arctic sea ice thickness and volume: new estimates and implications for trends |
title_full_unstemmed |
Uncertainties in Arctic sea ice thickness and volume: new estimates and implications for trends |
title_sort |
uncertainties in arctic sea ice thickness and volume: new estimates and implications for trends |
publisher |
HAL CCSD |
publishDate |
2014 |
url |
https://hal.univ-grenoble-alpes.fr/hal-03405842 https://hal.univ-grenoble-alpes.fr/hal-03405842/document https://hal.univ-grenoble-alpes.fr/hal-03405842/file/Zygmuntowska2014The_Cryosphere.pdf https://doi.org/10.5194/tc-8-705-2014 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Basin Arctic Sea ice The Cryosphere |
genre_facet |
Arctic Basin Arctic Sea ice The Cryosphere |
op_source |
ISSN: 1994-0424 EISSN: 1994-0416 The Cryosphere https://hal.univ-grenoble-alpes.fr/hal-03405842 The Cryosphere, Copernicus 2014, 8 (2), pp.705 - 720. ⟨10.5194/tc-8-705-2014⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-8-705-2014 hal-03405842 https://hal.univ-grenoble-alpes.fr/hal-03405842 https://hal.univ-grenoble-alpes.fr/hal-03405842/document https://hal.univ-grenoble-alpes.fr/hal-03405842/file/Zygmuntowska2014The_Cryosphere.pdf doi:10.5194/tc-8-705-2014 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.5194/tc-8-705-2014 |
container_title |
The Cryosphere |
container_volume |
8 |
container_issue |
2 |
container_start_page |
705 |
op_container_end_page |
720 |
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1766303391817924608 |