The life cycle of small- to medium-sized icebergs in the Amundsen Sea Embayment
An object-based method for automatic iceberg detection has been applied to Advanced Synthetic Aperture Radar images in the Amundsen Sea Embayment (ASE), Antarctica. The images were acquired between 1 January 2006 and 8 April 2012 under varying meteorological, oceanographic and sea-ice conditions. Du...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Norwegian Polar Institute
2019-08-01
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| Series: | Polar Research |
| Subjects: | |
| Online Access: | https://polarresearch.net/index.php/polar/article/view/3313/9358 |
| _version_ | 1811330062946926592 |
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| author | Aleksandra K. Mazur Anna K. Wåhlin Ola Kalén |
| author_facet | Aleksandra K. Mazur Anna K. Wåhlin Ola Kalén |
| author_sort | Aleksandra K. Mazur |
| collection | DOAJ |
| description | An object-based method for automatic iceberg detection has been applied to Advanced Synthetic Aperture Radar images in the Amundsen Sea Embayment (ASE), Antarctica. The images were acquired between 1 January 2006 and 8 April 2012 under varying meteorological, oceanographic and sea-ice conditions. During this time period, the icebergs were counted (average 1370 ± 50) and their surface area was estimated (average 1537.5 km2). The average surface area was about 2.5 times larger than the annual calved area (620 km2), indicating that the average iceberg age in the ASE is about 2.5 years, which was confirmed by observed residence times based on drift tracks. Most of the ASE icebergs were less than 1500 m long, and almost 90% of them were smaller than 2 km2. The proportion of small- and medium-sized icebergs (84.4%) was significantly higher than in the open ocean, where large icebergs (>10 km2) account for nearly the whole iceberg surface area. The opposite was true for the freshly calved icebergs in the ASE. The data indicate that the creation of icebergs in the ASE is dominated by steady small- to medium-scale calving from ice shelves fringing the embayment. In addition, rare calving events of giant icebergs occur on a decadal timescale. There is also some import of icebergs from the Bellingshausen Sea further east along the coast, in particular after large calving events there. |
| first_indexed | 2024-04-13T15:56:00Z |
| format | Article |
| id | doaj.art-229d01d769af42bebeb85c9f88f6dbe4 |
| institution | Directory Open Access Journal |
| issn | 1751-8369 |
| language | English |
| last_indexed | 2024-04-13T15:56:00Z |
| publishDate | 2019-08-01 |
| publisher | Norwegian Polar Institute |
| record_format | Article |
| series | Polar Research |
| spelling | doaj.art-229d01d769af42bebeb85c9f88f6dbe42022-12-22T02:40:42ZengNorwegian Polar InstitutePolar Research1751-83692019-08-0138011710.33265/polar.v38.33133313The life cycle of small- to medium-sized icebergs in the Amundsen Sea EmbaymentAleksandra K. Mazur0Anna K. Wåhlin1Ola Kalén2Department of Marine Sciences, University of Gothenburg, Göteborg, SwedenDepartment of Marine Sciences, University of Gothenburg, Göteborg, SwedenSwedish Meteorological and Hydrological Institute, Göteborg, SwedenAn object-based method for automatic iceberg detection has been applied to Advanced Synthetic Aperture Radar images in the Amundsen Sea Embayment (ASE), Antarctica. The images were acquired between 1 January 2006 and 8 April 2012 under varying meteorological, oceanographic and sea-ice conditions. During this time period, the icebergs were counted (average 1370 ± 50) and their surface area was estimated (average 1537.5 km2). The average surface area was about 2.5 times larger than the annual calved area (620 km2), indicating that the average iceberg age in the ASE is about 2.5 years, which was confirmed by observed residence times based on drift tracks. Most of the ASE icebergs were less than 1500 m long, and almost 90% of them were smaller than 2 km2. The proportion of small- and medium-sized icebergs (84.4%) was significantly higher than in the open ocean, where large icebergs (>10 km2) account for nearly the whole iceberg surface area. The opposite was true for the freshly calved icebergs in the ASE. The data indicate that the creation of icebergs in the ASE is dominated by steady small- to medium-scale calving from ice shelves fringing the embayment. In addition, rare calving events of giant icebergs occur on a decadal timescale. There is also some import of icebergs from the Bellingshausen Sea further east along the coast, in particular after large calving events there.https://polarresearch.net/index.php/polar/article/view/3313/9358Satellite radar dataobject-based image analysisiceberg size distributioniceberg annual variations |
| spellingShingle | Aleksandra K. Mazur Anna K. Wåhlin Ola Kalén The life cycle of small- to medium-sized icebergs in the Amundsen Sea Embayment Polar Research Satellite radar data object-based image analysis iceberg size distribution iceberg annual variations |
| title | The life cycle of small- to medium-sized icebergs in the Amundsen Sea Embayment |
| title_full | The life cycle of small- to medium-sized icebergs in the Amundsen Sea Embayment |
| title_fullStr | The life cycle of small- to medium-sized icebergs in the Amundsen Sea Embayment |
| title_full_unstemmed | The life cycle of small- to medium-sized icebergs in the Amundsen Sea Embayment |
| title_short | The life cycle of small- to medium-sized icebergs in the Amundsen Sea Embayment |
| title_sort | life cycle of small to medium sized icebergs in the amundsen sea embayment |
| topic | Satellite radar data object-based image analysis iceberg size distribution iceberg annual variations |
| url | https://polarresearch.net/index.php/polar/article/view/3313/9358 |
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