Extreme keel drafts in the Fram Strait 2006-2011
Knowledge about extreme keel drafts is needed for appropriate design of offshore installations in ice ridge infested waters. Ice drafts were measured with upward looking sonar by the Norwegian Polar Institute in the western part of the Fram Strait along 79°N in the period 2006 to 2011. This is where...
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Port and Ocean Engineering under Arctic Conditions, POAC
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ftntnutrondheimi:oai:ntnuopen.ntnu.no:11250/2394937 2023-06-11T04:07:22+02:00 Extreme keel drafts in the Fram Strait 2006-2011 Ekeberg, Ole-Christian Høyland, Knut Vilhelm Hansen, Edmond 2013-11-21T12:34:54Z application/pdf http://hdl.handle.net/11250/2394937 eng eng Port and Ocean Engineering under Arctic Conditions, POAC Palojarvi, Arttu; Tuhkuri, Jukka [Eds.] The proceedings of the 22nd International Conference on Port and Ocean Engineering under Arctic Conditions Proceedings - International Conference on Port and Ocean Engineering under Arctic Conditions, Port and Ocean Engineering under Arctic Conditions, 2013 urn:isbn:978-952-60-3635-9 urn:issn:0376-6756 http://hdl.handle.net/11250/2394937 cristin:1067914 Chapter Peer reviewed 2013 ftntnutrondheimi 2023-05-10T22:45:25Z Knowledge about extreme keel drafts is needed for appropriate design of offshore installations in ice ridge infested waters. Ice drafts were measured with upward looking sonar by the Norwegian Polar Institute in the western part of the Fram Strait along 79°N in the period 2006 to 2011. This is where the Transpolar Drift exits the Arctic Ocean, and the ice consists of a mixture of first-year and old ice originating from most parts of the Arctic Ocean. In total, 8 year-long deployments at 4 locations were analyzed. A generalized Pareto distribution was fitted to all ridges deeper than 17 m. This only amounts to a small fraction of all the ridges, but follows the methodology common for the calculation of extremes. All ridges deeper than 25 m were investigated prior to the analysis to ensure that no icebergs or other misidentified features were included. In total, 5 identified ridges were removed. The deepest ridge observed in the period was 35 m deep and 5 more ridges were deeper than 30 m in these 8 deployment seasons. Since the shape parameter in the generalized Pareto Distribution was close to zero the distribution could be simplified into an exponential distribution. Assuming an exponential distribution gave an estimated 100-year return value in the range 37 to 41 m. publishedVersion Article in Journal/Newspaper Arctic Arctic Arctic Ocean Fram Strait Iceberg* Norwegian Polar Institute NTNU Open Archive (Norwegian University of Science and Technology) Arctic Arctic Ocean |
institution |
Open Polar |
collection |
NTNU Open Archive (Norwegian University of Science and Technology) |
op_collection_id |
ftntnutrondheimi |
language |
English |
description |
Knowledge about extreme keel drafts is needed for appropriate design of offshore installations in ice ridge infested waters. Ice drafts were measured with upward looking sonar by the Norwegian Polar Institute in the western part of the Fram Strait along 79°N in the period 2006 to 2011. This is where the Transpolar Drift exits the Arctic Ocean, and the ice consists of a mixture of first-year and old ice originating from most parts of the Arctic Ocean. In total, 8 year-long deployments at 4 locations were analyzed. A generalized Pareto distribution was fitted to all ridges deeper than 17 m. This only amounts to a small fraction of all the ridges, but follows the methodology common for the calculation of extremes. All ridges deeper than 25 m were investigated prior to the analysis to ensure that no icebergs or other misidentified features were included. In total, 5 identified ridges were removed. The deepest ridge observed in the period was 35 m deep and 5 more ridges were deeper than 30 m in these 8 deployment seasons. Since the shape parameter in the generalized Pareto Distribution was close to zero the distribution could be simplified into an exponential distribution. Assuming an exponential distribution gave an estimated 100-year return value in the range 37 to 41 m. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Ekeberg, Ole-Christian Høyland, Knut Vilhelm Hansen, Edmond |
spellingShingle |
Ekeberg, Ole-Christian Høyland, Knut Vilhelm Hansen, Edmond Extreme keel drafts in the Fram Strait 2006-2011 |
author_facet |
Ekeberg, Ole-Christian Høyland, Knut Vilhelm Hansen, Edmond |
author_sort |
Ekeberg, Ole-Christian |
title |
Extreme keel drafts in the Fram Strait 2006-2011 |
title_short |
Extreme keel drafts in the Fram Strait 2006-2011 |
title_full |
Extreme keel drafts in the Fram Strait 2006-2011 |
title_fullStr |
Extreme keel drafts in the Fram Strait 2006-2011 |
title_full_unstemmed |
Extreme keel drafts in the Fram Strait 2006-2011 |
title_sort |
extreme keel drafts in the fram strait 2006-2011 |
publisher |
Port and Ocean Engineering under Arctic Conditions, POAC |
publishDate |
2013 |
url |
http://hdl.handle.net/11250/2394937 |
geographic |
Arctic Arctic Ocean |
geographic_facet |
Arctic Arctic Ocean |
genre |
Arctic Arctic Arctic Ocean Fram Strait Iceberg* Norwegian Polar Institute |
genre_facet |
Arctic Arctic Arctic Ocean Fram Strait Iceberg* Norwegian Polar Institute |
op_relation |
Palojarvi, Arttu; Tuhkuri, Jukka [Eds.] The proceedings of the 22nd International Conference on Port and Ocean Engineering under Arctic Conditions Proceedings - International Conference on Port and Ocean Engineering under Arctic Conditions, Port and Ocean Engineering under Arctic Conditions, 2013 urn:isbn:978-952-60-3635-9 urn:issn:0376-6756 http://hdl.handle.net/11250/2394937 cristin:1067914 |
_version_ |
1768380523402493952 |