Quantifying dissolution rates of Antarctic icebergs in open water
At any one time 130 000 icebergs are afloat in the Southern Ocean; 97% of these are too small to be registered in current satellite-based databases, yet the melting of these small icebergs provides a major input to the Southern Ocean. We use a unique set of visual size observations of 53 000 iceberg...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Cambridge University Press
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| Series: | Annals of Glaciology |
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| Online Access: | https://www.cambridge.org/core/product/identifier/S0260305523000265/type/journal_article |
| _version_ | 1797834645060976640 |
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| author | Olav Orheim A. Barry Giles T. H. (Jo) Jacka Geir Moholdt |
| author_facet | Olav Orheim A. Barry Giles T. H. (Jo) Jacka Geir Moholdt |
| author_sort | Olav Orheim |
| collection | DOAJ |
| description | At any one time 130 000 icebergs are afloat in the Southern Ocean; 97% of these are too small to be registered in current satellite-based databases, yet the melting of these small icebergs provides a major input to the Southern Ocean. We use a unique set of visual size observations of 53 000 icebergs in the South Atlantic Ocean, the SCAR International Iceberg Database, to derive average iceberg dissolution rates. Fracture into two parts is the dominant dissolution process for tabular icebergs, with an average half-life of 30 days for icebergs <4 km length and 60 days for larger icebergs. Complete shatter producing many icebergs <1 km length is rare. A side attrition rate of 0.23 m d−1 combined with drift speed of 6 km d−1, or any proportional change in both numbers fits the observed changes in iceberg distribution. The largest injection into the Southern Ocean of fresh water and any iceberg-transported material takes place in a ~2.3 × 10⁶ km2 zone extending east-northeast from the Antarctic Peninsula to the Greenwich meridian. The iceberg contribution to salinities and temperatures, with maximum contribution north of the Weddell Sea, differs in some regions, from those indicated by tracking large icebergs. |
| first_indexed | 2024-04-09T14:41:29Z |
| format | Article |
| id | doaj.art-9dfa9665f2d1468fbfaa0416f230d5e4 |
| institution | Directory Open Access Journal |
| issn | 0260-3055 1727-5644 |
| language | English |
| last_indexed | 2024-04-09T14:41:29Z |
| publisher | Cambridge University Press |
| record_format | Article |
| series | Annals of Glaciology |
| spelling | doaj.art-9dfa9665f2d1468fbfaa0416f230d5e42023-05-03T07:52:34ZengCambridge University PressAnnals of Glaciology0260-30551727-564411110.1017/aog.2023.26Quantifying dissolution rates of Antarctic icebergs in open waterOlav Orheim0A. Barry Giles1T. H. (Jo) Jacka2Geir Moholdt3Norsk Polarinstitutt, 9296 Tromsø, NorwayInstitute for Marine and Antarctic Studies (IMAS), University of Tasmania, Private Bag 80, Hobart, Tasmania 7001, AustraliaAntarctic Climate Program, Australian Antarctic Division, 203 Channel Highway, Kingston, Tasmania 7050, AustraliaNorsk Polarinstitutt, 9296 Tromsø, NorwayAt any one time 130 000 icebergs are afloat in the Southern Ocean; 97% of these are too small to be registered in current satellite-based databases, yet the melting of these small icebergs provides a major input to the Southern Ocean. We use a unique set of visual size observations of 53 000 icebergs in the South Atlantic Ocean, the SCAR International Iceberg Database, to derive average iceberg dissolution rates. Fracture into two parts is the dominant dissolution process for tabular icebergs, with an average half-life of 30 days for icebergs <4 km length and 60 days for larger icebergs. Complete shatter producing many icebergs <1 km length is rare. A side attrition rate of 0.23 m d−1 combined with drift speed of 6 km d−1, or any proportional change in both numbers fits the observed changes in iceberg distribution. The largest injection into the Southern Ocean of fresh water and any iceberg-transported material takes place in a ~2.3 × 10⁶ km2 zone extending east-northeast from the Antarctic Peninsula to the Greenwich meridian. The iceberg contribution to salinities and temperatures, with maximum contribution north of the Weddell Sea, differs in some regions, from those indicated by tracking large icebergs.https://www.cambridge.org/core/product/identifier/S0260305523000265/type/journal_articleAntarctic glaciologyice/ocean interactionsiceberg calvingicebergs |
| spellingShingle | Olav Orheim A. Barry Giles T. H. (Jo) Jacka Geir Moholdt Quantifying dissolution rates of Antarctic icebergs in open water Annals of Glaciology Antarctic glaciology ice/ocean interactions iceberg calving icebergs |
| title | Quantifying dissolution rates of Antarctic icebergs in open water |
| title_full | Quantifying dissolution rates of Antarctic icebergs in open water |
| title_fullStr | Quantifying dissolution rates of Antarctic icebergs in open water |
| title_full_unstemmed | Quantifying dissolution rates of Antarctic icebergs in open water |
| title_short | Quantifying dissolution rates of Antarctic icebergs in open water |
| title_sort | quantifying dissolution rates of antarctic icebergs in open water |
| topic | Antarctic glaciology ice/ocean interactions iceberg calving icebergs |
| url | https://www.cambridge.org/core/product/identifier/S0260305523000265/type/journal_article |
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