An Object-Based Classification Method to Detect Methane Ebullition Bubbles in Early Winter Lake Ice
Thermokarst lakes in the Arctic and Subarctic release carbon from thawing permafrost in the form of methane and carbon dioxide with important implications for regional and global carbon cycles. Lake ice impedes the release of gas during the winter. For instance, bubbles released from lake sediments...
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Online Access: | https://doi.org/10.3390/rs11070822 https://doaj.org/article/3ce701ea234647649e7f5cac729f7ee7 |
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ftdoajarticles:oai:doaj.org/article:3ce701ea234647649e7f5cac729f7ee7 2023-05-15T15:17:12+02:00 An Object-Based Classification Method to Detect Methane Ebullition Bubbles in Early Winter Lake Ice Prajna Lindgren Guido Grosse Franz J. Meyer Katey Walter Anthony 2019-04-01T00:00:00Z https://doi.org/10.3390/rs11070822 https://doaj.org/article/3ce701ea234647649e7f5cac729f7ee7 EN eng MDPI AG https://www.mdpi.com/2072-4292/11/7/822 https://doaj.org/toc/2072-4292 2072-4292 doi:10.3390/rs11070822 https://doaj.org/article/3ce701ea234647649e7f5cac729f7ee7 Remote Sensing, Vol 11, Iss 7, p 822 (2019) methane ebullition mapping lake ice object-based image classification aerial photography thermokarst lake permafrost carbon feedback Science Q article 2019 ftdoajarticles https://doi.org/10.3390/rs11070822 2022-12-31T11:26:14Z Thermokarst lakes in the Arctic and Subarctic release carbon from thawing permafrost in the form of methane and carbon dioxide with important implications for regional and global carbon cycles. Lake ice impedes the release of gas during the winter. For instance, bubbles released from lake sediments become trapped in downward growing lake ice, resulting in vertically-oriented bubble columns in the ice that are visible on the lake surface. We here describe a classification technique using an object-based image analysis (OBIA) framework to successfully map ebullition bubbles in airborne imagery of early winter ice on an interior Alaska thermokarst lake. Ebullition bubbles appear as white patches in high-resolution optical remote sensing images of snow-free lake ice acquired in early winter and, thus, can be mapped across whole lake areas. We used high-resolution (9–11 cm) aerial images acquired two and four days following freeze-up in the years 2011 and 2012, respectively. The design of multiresolution segmentation and region-specific classification rulesets allowed the identification of bubble features and separation from other confounding factors such as snow, submerged and floating vegetation, shadows, and open water. The OBIA technique had an accuracy of >95% for mapping ebullition bubble patches in early winter lake ice. Overall, we mapped 1195 and 1860 ebullition bubble patches in the 2011 and 2012 images, respectively. The percent surface area of lake ice covered with ebullition bubble patches for 2011 was 2.14% and for 2012 was 2.67%, representing a conservative whole lake estimate of bubble patches compared to ground surveys usually conducted on thicker ice 10 or more days after freeze-up. Our findings suggest that the information derived from high-resolution optical images of lake ice can supplement spatially limited field sampling methods to better estimate methane flux from individual lakes. The method can also be used to improve estimates of methane ebullition from numerous lakes within larger ... Article in Journal/Newspaper Arctic Ice permafrost Subarctic Thermokarst Alaska Directory of Open Access Journals: DOAJ Articles Arctic Winter Lake ENVELOPE(-112.918,-112.918,64.484,64.484) Remote Sensing 11 7 822 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
methane ebullition mapping lake ice object-based image classification aerial photography thermokarst lake permafrost carbon feedback Science Q |
spellingShingle |
methane ebullition mapping lake ice object-based image classification aerial photography thermokarst lake permafrost carbon feedback Science Q Prajna Lindgren Guido Grosse Franz J. Meyer Katey Walter Anthony An Object-Based Classification Method to Detect Methane Ebullition Bubbles in Early Winter Lake Ice |
topic_facet |
methane ebullition mapping lake ice object-based image classification aerial photography thermokarst lake permafrost carbon feedback Science Q |
description |
Thermokarst lakes in the Arctic and Subarctic release carbon from thawing permafrost in the form of methane and carbon dioxide with important implications for regional and global carbon cycles. Lake ice impedes the release of gas during the winter. For instance, bubbles released from lake sediments become trapped in downward growing lake ice, resulting in vertically-oriented bubble columns in the ice that are visible on the lake surface. We here describe a classification technique using an object-based image analysis (OBIA) framework to successfully map ebullition bubbles in airborne imagery of early winter ice on an interior Alaska thermokarst lake. Ebullition bubbles appear as white patches in high-resolution optical remote sensing images of snow-free lake ice acquired in early winter and, thus, can be mapped across whole lake areas. We used high-resolution (9–11 cm) aerial images acquired two and four days following freeze-up in the years 2011 and 2012, respectively. The design of multiresolution segmentation and region-specific classification rulesets allowed the identification of bubble features and separation from other confounding factors such as snow, submerged and floating vegetation, shadows, and open water. The OBIA technique had an accuracy of >95% for mapping ebullition bubble patches in early winter lake ice. Overall, we mapped 1195 and 1860 ebullition bubble patches in the 2011 and 2012 images, respectively. The percent surface area of lake ice covered with ebullition bubble patches for 2011 was 2.14% and for 2012 was 2.67%, representing a conservative whole lake estimate of bubble patches compared to ground surveys usually conducted on thicker ice 10 or more days after freeze-up. Our findings suggest that the information derived from high-resolution optical images of lake ice can supplement spatially limited field sampling methods to better estimate methane flux from individual lakes. The method can also be used to improve estimates of methane ebullition from numerous lakes within larger ... |
format |
Article in Journal/Newspaper |
author |
Prajna Lindgren Guido Grosse Franz J. Meyer Katey Walter Anthony |
author_facet |
Prajna Lindgren Guido Grosse Franz J. Meyer Katey Walter Anthony |
author_sort |
Prajna Lindgren |
title |
An Object-Based Classification Method to Detect Methane Ebullition Bubbles in Early Winter Lake Ice |
title_short |
An Object-Based Classification Method to Detect Methane Ebullition Bubbles in Early Winter Lake Ice |
title_full |
An Object-Based Classification Method to Detect Methane Ebullition Bubbles in Early Winter Lake Ice |
title_fullStr |
An Object-Based Classification Method to Detect Methane Ebullition Bubbles in Early Winter Lake Ice |
title_full_unstemmed |
An Object-Based Classification Method to Detect Methane Ebullition Bubbles in Early Winter Lake Ice |
title_sort |
object-based classification method to detect methane ebullition bubbles in early winter lake ice |
publisher |
MDPI AG |
publishDate |
2019 |
url |
https://doi.org/10.3390/rs11070822 https://doaj.org/article/3ce701ea234647649e7f5cac729f7ee7 |
long_lat |
ENVELOPE(-112.918,-112.918,64.484,64.484) |
geographic |
Arctic Winter Lake |
geographic_facet |
Arctic Winter Lake |
genre |
Arctic Ice permafrost Subarctic Thermokarst Alaska |
genre_facet |
Arctic Ice permafrost Subarctic Thermokarst Alaska |
op_source |
Remote Sensing, Vol 11, Iss 7, p 822 (2019) |
op_relation |
https://www.mdpi.com/2072-4292/11/7/822 https://doaj.org/toc/2072-4292 2072-4292 doi:10.3390/rs11070822 https://doaj.org/article/3ce701ea234647649e7f5cac729f7ee7 |
op_doi |
https://doi.org/10.3390/rs11070822 |
container_title |
Remote Sensing |
container_volume |
11 |
container_issue |
7 |
container_start_page |
822 |
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1766347466271096832 |