A Comparative Study of Active Rock Glaciers Mapped from Geomorphic- and Kinematic-Based Approaches in Daxue Shan, Southeast Tibetan Plateau
Active rock glaciers (ARGs) are important permafrost landforms in alpine regions. Identifying ARGs has mainly relied on visual interpretation of their geomorphic characteristics with optical remote sensing images, while mapping ARGs from their kinematic features has also become popular in recent yea...
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ftdoajarticles:oai:doaj.org/article:32e6e786bb844c3292f3cc9a62db1706 2023-05-15T17:57:21+02:00 A Comparative Study of Active Rock Glaciers Mapped from Geomorphic- and Kinematic-Based Approaches in Daxue Shan, Southeast Tibetan Plateau Jiaxin Cai Xiaowen Wang Guoxiang Liu Bing Yu 2021-12-01T00:00:00Z https://doi.org/10.3390/rs13234931 https://doaj.org/article/32e6e786bb844c3292f3cc9a62db1706 EN eng MDPI AG https://www.mdpi.com/2072-4292/13/23/4931 https://doaj.org/toc/2072-4292 doi:10.3390/rs13234931 2072-4292 https://doaj.org/article/32e6e786bb844c3292f3cc9a62db1706 Remote Sensing, Vol 13, Iss 4931, p 4931 (2021) rock glacier inventory surface deformation mountain permafrost Science Q article 2021 ftdoajarticles https://doi.org/10.3390/rs13234931 2022-12-31T16:29:00Z Active rock glaciers (ARGs) are important permafrost landforms in alpine regions. Identifying ARGs has mainly relied on visual interpretation of their geomorphic characteristics with optical remote sensing images, while mapping ARGs from their kinematic features has also become popular in recent years. However, a thorough comparison of geomorphic- and kinematic-based inventories of ARGs has not been carried out. In this study, we employed a multi-temporal interferometric synthetic aperture radar (InSAR) technique to derive the mean annual surface displacement velocity over the Daxue Shan, Southeast Tibet Plateau. We then compiled a rock glacier inventory by synergistically interpreting the InSAR-derived surface displacements and geomorphic features based on Google Earth images. Our InSAR-assist kinematic-based inventory (KBI) was further compared with a pre-existing geomorphic-based inventory (GBI) of rock glaciers in Daxue Shan. The results show that our InSAR-assist inventory consists of 344 ARGs, 36% (i.e., 125) more than that derived from the geomorphic-based method (i.e., 251). Only 32 ARGs in the GBI are not included in the KBI. Among the 219 ARGs detected by both approaches, the ones with area differences of more than 20% account for about 32% (i.e., 70 ARGs). The mean downslope velocities of ARGs calculated from InSAR are between 2.8 and 107.4 mm∙a −1 . Our comparative analyses show that ARGs mapping from the InSAR-based kinematic approach is more efficient and accurate than the geomorphic-based approach. Nonetheless, the completeness of the InSAR-assist KBI is affected by the SAR data acquisition time, signal decorrelation, geometric distortion of SAR images, and the sensitivity of the InSAR measurement to ground deformation. We suggest that the kinematic-based approach should be utilized in future ARGs-based studies such as regional permafrost distribution assessment and water storage estimates. Article in Journal/Newspaper permafrost Directory of Open Access Journals: DOAJ Articles Remote Sensing 13 23 4931 |
institution |
Open Polar |
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Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
rock glacier inventory surface deformation mountain permafrost Science Q |
spellingShingle |
rock glacier inventory surface deformation mountain permafrost Science Q Jiaxin Cai Xiaowen Wang Guoxiang Liu Bing Yu A Comparative Study of Active Rock Glaciers Mapped from Geomorphic- and Kinematic-Based Approaches in Daxue Shan, Southeast Tibetan Plateau |
topic_facet |
rock glacier inventory surface deformation mountain permafrost Science Q |
description |
Active rock glaciers (ARGs) are important permafrost landforms in alpine regions. Identifying ARGs has mainly relied on visual interpretation of their geomorphic characteristics with optical remote sensing images, while mapping ARGs from their kinematic features has also become popular in recent years. However, a thorough comparison of geomorphic- and kinematic-based inventories of ARGs has not been carried out. In this study, we employed a multi-temporal interferometric synthetic aperture radar (InSAR) technique to derive the mean annual surface displacement velocity over the Daxue Shan, Southeast Tibet Plateau. We then compiled a rock glacier inventory by synergistically interpreting the InSAR-derived surface displacements and geomorphic features based on Google Earth images. Our InSAR-assist kinematic-based inventory (KBI) was further compared with a pre-existing geomorphic-based inventory (GBI) of rock glaciers in Daxue Shan. The results show that our InSAR-assist inventory consists of 344 ARGs, 36% (i.e., 125) more than that derived from the geomorphic-based method (i.e., 251). Only 32 ARGs in the GBI are not included in the KBI. Among the 219 ARGs detected by both approaches, the ones with area differences of more than 20% account for about 32% (i.e., 70 ARGs). The mean downslope velocities of ARGs calculated from InSAR are between 2.8 and 107.4 mm∙a −1 . Our comparative analyses show that ARGs mapping from the InSAR-based kinematic approach is more efficient and accurate than the geomorphic-based approach. Nonetheless, the completeness of the InSAR-assist KBI is affected by the SAR data acquisition time, signal decorrelation, geometric distortion of SAR images, and the sensitivity of the InSAR measurement to ground deformation. We suggest that the kinematic-based approach should be utilized in future ARGs-based studies such as regional permafrost distribution assessment and water storage estimates. |
format |
Article in Journal/Newspaper |
author |
Jiaxin Cai Xiaowen Wang Guoxiang Liu Bing Yu |
author_facet |
Jiaxin Cai Xiaowen Wang Guoxiang Liu Bing Yu |
author_sort |
Jiaxin Cai |
title |
A Comparative Study of Active Rock Glaciers Mapped from Geomorphic- and Kinematic-Based Approaches in Daxue Shan, Southeast Tibetan Plateau |
title_short |
A Comparative Study of Active Rock Glaciers Mapped from Geomorphic- and Kinematic-Based Approaches in Daxue Shan, Southeast Tibetan Plateau |
title_full |
A Comparative Study of Active Rock Glaciers Mapped from Geomorphic- and Kinematic-Based Approaches in Daxue Shan, Southeast Tibetan Plateau |
title_fullStr |
A Comparative Study of Active Rock Glaciers Mapped from Geomorphic- and Kinematic-Based Approaches in Daxue Shan, Southeast Tibetan Plateau |
title_full_unstemmed |
A Comparative Study of Active Rock Glaciers Mapped from Geomorphic- and Kinematic-Based Approaches in Daxue Shan, Southeast Tibetan Plateau |
title_sort |
comparative study of active rock glaciers mapped from geomorphic- and kinematic-based approaches in daxue shan, southeast tibetan plateau |
publisher |
MDPI AG |
publishDate |
2021 |
url |
https://doi.org/10.3390/rs13234931 https://doaj.org/article/32e6e786bb844c3292f3cc9a62db1706 |
genre |
permafrost |
genre_facet |
permafrost |
op_source |
Remote Sensing, Vol 13, Iss 4931, p 4931 (2021) |
op_relation |
https://www.mdpi.com/2072-4292/13/23/4931 https://doaj.org/toc/2072-4292 doi:10.3390/rs13234931 2072-4292 https://doaj.org/article/32e6e786bb844c3292f3cc9a62db1706 |
op_doi |
https://doi.org/10.3390/rs13234931 |
container_title |
Remote Sensing |
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13 |
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23 |
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4931 |
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1766165748544176128 |