Firn Evolution at Camp Century, Greenland: 1966–2100
Camp Century is an American military base built in 1959 under the surface of the Greenland ice sheet and decommissioned in 1967. Here, we use outputs from RACMO2.3p2 and CanESM2 climate models, adjusted to meteorological observations, and a firn model to simulate the firn density and temperature at...
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ftdoajarticles:oai:doaj.org/article:62403c89850048d087256446557ced82 2023-05-15T16:26:48+02:00 Firn Evolution at Camp Century, Greenland: 1966–2100 Baptiste Vandecrux William Colgan Anne M. Solgaard Jørgen Peder Steffensen Nanna B. Karlsson 2021-03-01T00:00:00Z https://doi.org/10.3389/feart.2021.578978 https://doaj.org/article/62403c89850048d087256446557ced82 EN eng Frontiers Media S.A. https://www.frontiersin.org/articles/10.3389/feart.2021.578978/full https://doaj.org/toc/2296-6463 2296-6463 doi:10.3389/feart.2021.578978 https://doaj.org/article/62403c89850048d087256446557ced82 Frontiers in Earth Science, Vol 9 (2021) greenland ice sheet firn surface mass balance accumulation camp century future climate Science Q article 2021 ftdoajarticles https://doi.org/10.3389/feart.2021.578978 2022-12-31T13:29:30Z Camp Century is an American military base built in 1959 under the surface of the Greenland ice sheet and decommissioned in 1967. Here, we use outputs from RACMO2.3p2 and CanESM2 climate models, adjusted to meteorological observations, and a firn model to simulate the firn density and temperature at Camp Century between 1966 and 2100. The model output is evaluated against an extensive set of firn 3observations and three Representative Concentration Pathways (RCP2.6, 4.5 and 8.5) are considered as future scenarios. Our model suggests that the upper horizon of the Camp Century debris field – observed at a depth of 32 m in 2017 – will continue to be buried by persistent net accumulation over the next eighty years under all RCP scenarios. This horizon depth will be between 58 and 64 m in 2100, depending on the RCP scenario. We estimate a maximum meltwater percolation depth of 1.1 m under all RCP scenarios. We therefore find it extremely unlikely that surface meltwater interacts with the subsurface debris field at Camp Century before 2100 under all RCP scenarios. Camp Century’s future is representative of the firn area in northwestern Greenland, bound to shift from dry snow to a percolation regime. Our model suggests that 10 m firn temperatures at Camp Century will increase from −24.0°C in 1966 to −21.3, −20.0 and −18.6°C in 2100 under the RCP2.6, 4.5 and 8.5 scenarios, respectively. We reveal a previously unknown warm bias in air temperatures simulated at Camp Century by both RACMO2.3p2 and CanESM2 climate models which needs to be accounted for when using these models to predict melt, firn evolution and sea-level contribution of the Greenland ice sheet. We also present novel in situ measurements of firn compaction rates, which indicate that about 25% of firn compaction of the top 62 m of firn occurs below 20 m depth. This highlights the importance of deep-firn compaction measurements for model evaluation and correction of altimetry products. Article in Journal/Newspaper Greenland Ice Sheet Directory of Open Access Journals: DOAJ Articles Greenland Frontiers in Earth Science 9 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
greenland ice sheet firn surface mass balance accumulation camp century future climate Science Q |
spellingShingle |
greenland ice sheet firn surface mass balance accumulation camp century future climate Science Q Baptiste Vandecrux William Colgan Anne M. Solgaard Jørgen Peder Steffensen Nanna B. Karlsson Firn Evolution at Camp Century, Greenland: 1966–2100 |
topic_facet |
greenland ice sheet firn surface mass balance accumulation camp century future climate Science Q |
description |
Camp Century is an American military base built in 1959 under the surface of the Greenland ice sheet and decommissioned in 1967. Here, we use outputs from RACMO2.3p2 and CanESM2 climate models, adjusted to meteorological observations, and a firn model to simulate the firn density and temperature at Camp Century between 1966 and 2100. The model output is evaluated against an extensive set of firn 3observations and three Representative Concentration Pathways (RCP2.6, 4.5 and 8.5) are considered as future scenarios. Our model suggests that the upper horizon of the Camp Century debris field – observed at a depth of 32 m in 2017 – will continue to be buried by persistent net accumulation over the next eighty years under all RCP scenarios. This horizon depth will be between 58 and 64 m in 2100, depending on the RCP scenario. We estimate a maximum meltwater percolation depth of 1.1 m under all RCP scenarios. We therefore find it extremely unlikely that surface meltwater interacts with the subsurface debris field at Camp Century before 2100 under all RCP scenarios. Camp Century’s future is representative of the firn area in northwestern Greenland, bound to shift from dry snow to a percolation regime. Our model suggests that 10 m firn temperatures at Camp Century will increase from −24.0°C in 1966 to −21.3, −20.0 and −18.6°C in 2100 under the RCP2.6, 4.5 and 8.5 scenarios, respectively. We reveal a previously unknown warm bias in air temperatures simulated at Camp Century by both RACMO2.3p2 and CanESM2 climate models which needs to be accounted for when using these models to predict melt, firn evolution and sea-level contribution of the Greenland ice sheet. We also present novel in situ measurements of firn compaction rates, which indicate that about 25% of firn compaction of the top 62 m of firn occurs below 20 m depth. This highlights the importance of deep-firn compaction measurements for model evaluation and correction of altimetry products. |
format |
Article in Journal/Newspaper |
author |
Baptiste Vandecrux William Colgan Anne M. Solgaard Jørgen Peder Steffensen Nanna B. Karlsson |
author_facet |
Baptiste Vandecrux William Colgan Anne M. Solgaard Jørgen Peder Steffensen Nanna B. Karlsson |
author_sort |
Baptiste Vandecrux |
title |
Firn Evolution at Camp Century, Greenland: 1966–2100 |
title_short |
Firn Evolution at Camp Century, Greenland: 1966–2100 |
title_full |
Firn Evolution at Camp Century, Greenland: 1966–2100 |
title_fullStr |
Firn Evolution at Camp Century, Greenland: 1966–2100 |
title_full_unstemmed |
Firn Evolution at Camp Century, Greenland: 1966–2100 |
title_sort |
firn evolution at camp century, greenland: 1966–2100 |
publisher |
Frontiers Media S.A. |
publishDate |
2021 |
url |
https://doi.org/10.3389/feart.2021.578978 https://doaj.org/article/62403c89850048d087256446557ced82 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet |
genre_facet |
Greenland Ice Sheet |
op_source |
Frontiers in Earth Science, Vol 9 (2021) |
op_relation |
https://www.frontiersin.org/articles/10.3389/feart.2021.578978/full https://doaj.org/toc/2296-6463 2296-6463 doi:10.3389/feart.2021.578978 https://doaj.org/article/62403c89850048d087256446557ced82 |
op_doi |
https://doi.org/10.3389/feart.2021.578978 |
container_title |
Frontiers in Earth Science |
container_volume |
9 |
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1766015776585678848 |