Updated inventory of glacier ice in New Zealand based on 2016 satellite imagery
Abstract The only complete inventory of New Zealand glaciers was based on aerial photography starting in 1978. While there have been partial updates using 2002 and 2009 satellite data, most glaciers are still represented by the 1978 outlines in contemporary global glacier databases. The objective of...
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Language: | English |
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Online Access: | http://dx.doi.org/10.1017/jog.2020.78 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143020000787 |
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crcambridgeupr:10.1017/jog.2020.78 2024-06-23T07:54:15+00:00 Updated inventory of glacier ice in New Zealand based on 2016 satellite imagery Baumann, Sabine Anderson, Brian Chinn, Trevor Mackintosh, Andrew Collier, Catherine Lorrey, Andrew M. Rack, Wolfgang Purdie, Heather Eaves, Shaun 2020 http://dx.doi.org/10.1017/jog.2020.78 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143020000787 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by-nc-sa/4.0/ Journal of Glaciology volume 67, issue 261, page 13-26 ISSN 0022-1430 1727-5652 journal-article 2020 crcambridgeupr https://doi.org/10.1017/jog.2020.78 2024-06-12T04:03:25Z Abstract The only complete inventory of New Zealand glaciers was based on aerial photography starting in 1978. While there have been partial updates using 2002 and 2009 satellite data, most glaciers are still represented by the 1978 outlines in contemporary global glacier databases. The objective of this project is to establish an updated glacier inventory for New Zealand. We have used Landsat 8 OLI satellite imagery from February and March 2016 for delineating clean glaciers using a semi-automatic band ratio method and debris-covered glaciers using a maximum likelihood classification. The outlines have been checked against Sentinel-2 MSI data, which have a higher resolution. Manual post processing was necessary due to misclassifications (e.g. lakes, clouds), mapping in shadowed areas, and combining the clean and debris-covered parts into single glaciers. New Zealand glaciers cover an area of 794 ± 34 km 2 in 2016 with a debris-covered area of 10%. Of the 2918 glaciers, seven glaciers are >10 km 2 while 71% is <0.1 km 2 . The debris cover on those largest glaciers is >40%. Only 15 glaciers are located on the North Island. For a selection of glaciers, we were able to calculate the area reduction between the 1978 and 2016 inventories. Article in Journal/Newspaper Journal of Glaciology Cambridge University Press New Zealand Journal of Glaciology 67 261 13 26 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
description |
Abstract The only complete inventory of New Zealand glaciers was based on aerial photography starting in 1978. While there have been partial updates using 2002 and 2009 satellite data, most glaciers are still represented by the 1978 outlines in contemporary global glacier databases. The objective of this project is to establish an updated glacier inventory for New Zealand. We have used Landsat 8 OLI satellite imagery from February and March 2016 for delineating clean glaciers using a semi-automatic band ratio method and debris-covered glaciers using a maximum likelihood classification. The outlines have been checked against Sentinel-2 MSI data, which have a higher resolution. Manual post processing was necessary due to misclassifications (e.g. lakes, clouds), mapping in shadowed areas, and combining the clean and debris-covered parts into single glaciers. New Zealand glaciers cover an area of 794 ± 34 km 2 in 2016 with a debris-covered area of 10%. Of the 2918 glaciers, seven glaciers are >10 km 2 while 71% is <0.1 km 2 . The debris cover on those largest glaciers is >40%. Only 15 glaciers are located on the North Island. For a selection of glaciers, we were able to calculate the area reduction between the 1978 and 2016 inventories. |
format |
Article in Journal/Newspaper |
author |
Baumann, Sabine Anderson, Brian Chinn, Trevor Mackintosh, Andrew Collier, Catherine Lorrey, Andrew M. Rack, Wolfgang Purdie, Heather Eaves, Shaun |
spellingShingle |
Baumann, Sabine Anderson, Brian Chinn, Trevor Mackintosh, Andrew Collier, Catherine Lorrey, Andrew M. Rack, Wolfgang Purdie, Heather Eaves, Shaun Updated inventory of glacier ice in New Zealand based on 2016 satellite imagery |
author_facet |
Baumann, Sabine Anderson, Brian Chinn, Trevor Mackintosh, Andrew Collier, Catherine Lorrey, Andrew M. Rack, Wolfgang Purdie, Heather Eaves, Shaun |
author_sort |
Baumann, Sabine |
title |
Updated inventory of glacier ice in New Zealand based on 2016 satellite imagery |
title_short |
Updated inventory of glacier ice in New Zealand based on 2016 satellite imagery |
title_full |
Updated inventory of glacier ice in New Zealand based on 2016 satellite imagery |
title_fullStr |
Updated inventory of glacier ice in New Zealand based on 2016 satellite imagery |
title_full_unstemmed |
Updated inventory of glacier ice in New Zealand based on 2016 satellite imagery |
title_sort |
updated inventory of glacier ice in new zealand based on 2016 satellite imagery |
publisher |
Cambridge University Press (CUP) |
publishDate |
2020 |
url |
http://dx.doi.org/10.1017/jog.2020.78 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143020000787 |
geographic |
New Zealand |
geographic_facet |
New Zealand |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology volume 67, issue 261, page 13-26 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by-nc-sa/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2020.78 |
container_title |
Journal of Glaciology |
container_volume |
67 |
container_issue |
261 |
container_start_page |
13 |
op_container_end_page |
26 |
_version_ |
1802646330357579776 |