An integrated deep learning and object-based image analysis approach for mapping debris-covered glaciers

Evaluating glacial change and the subsequent water stores in high mountains is becoming increasingly necessary, and in order to do this, models need reliable and consistent glacier data. These often come from global inventories, usually constructed from multi-temporal satellite imagery. However, the...

Full description

Bibliographic Details
Main Authors: Daniel Jack Thomas, Benjamin Aubrey Robson, Adina Racoviteanu
Format: Article
Language:English
Published: Frontiers Media S.A. 2023-07-01
Series:Frontiers in Remote Sensing
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/frsen.2023.1161530/full
_version_ 1827904695709990912
author Daniel Jack Thomas
Daniel Jack Thomas
Daniel Jack Thomas
Benjamin Aubrey Robson
Benjamin Aubrey Robson
Adina Racoviteanu
author_facet Daniel Jack Thomas
Daniel Jack Thomas
Daniel Jack Thomas
Benjamin Aubrey Robson
Benjamin Aubrey Robson
Adina Racoviteanu
author_sort Daniel Jack Thomas
collection DOAJ
description Evaluating glacial change and the subsequent water stores in high mountains is becoming increasingly necessary, and in order to do this, models need reliable and consistent glacier data. These often come from global inventories, usually constructed from multi-temporal satellite imagery. However, there are limitations to these datasets. While clean ice can be mapped relatively easily using spectral band ratios, mapping debris-covered ice is more difficult due to the spectral similarity of supraglacial debris to the surrounding terrain. Therefore, analysts often employ manual delineation, a time-consuming and subjective approach to map debris-covered ice extents. Given the increasing prevalence of supraglacial debris in high mountain regions, such as High Mountain Asia, a systematic, objective approach is needed. The current study presents an approach for mapping debris-covered glaciers that integrates a convolutional neural network and object-based image analysis into one seamless classification workflow, applied to freely available and globally applicable Sentinel-2 multispectral, Landsat-8 thermal, Sentinel-1 interferometric coherence, and geomorphometric datasets. The approach is applied to three different domains in the Central Himalayan and the Karakoram ranges of High Mountain Asia that exhibit varying climatic regimes, topographies and debris-covered glacier characteristics. We evaluate the performance of the approach by comparison with a manually delineated glacier inventory, achieving F-score classification accuracies of 89.2%–93.7%. We also tested the performance of this approach on declassified panchromatic 1970 Corona KH-4B satellite imagery in the Manaslu region of Nepal, yielding accuracies of up to 88.4%. We find our approach to be robust, transferable to other regions, and accurate over regional (>4,000 km2) scales. Integrating object-based image analysis with deep-learning within a single workflow overcomes shortcomings associated with convolutional neural network classifications and permits a more flexible and robust approach for mapping debris-covered glaciers. The novel automated processing of panchromatic historical imagery, such as Corona KH-4B, opens the possibility of exploiting a wealth of multi-temporal data to understand past glacier changes.
first_indexed 2024-03-13T00:31:02Z
format Article
id doaj.art-794483c484744e08a59e21efd0eb9cb5
institution Directory Open Access Journal
issn 2673-6187
language English
last_indexed 2024-03-13T00:31:02Z
publishDate 2023-07-01
publisher Frontiers Media S.A.
record_format Article
series Frontiers in Remote Sensing
spelling doaj.art-794483c484744e08a59e21efd0eb9cb52023-07-10T15:00:39ZengFrontiers Media S.A.Frontiers in Remote Sensing2673-61872023-07-01410.3389/frsen.2023.11615301161530An integrated deep learning and object-based image analysis approach for mapping debris-covered glaciersDaniel Jack Thomas0Daniel Jack Thomas1Daniel Jack Thomas2Benjamin Aubrey Robson3Benjamin Aubrey Robson4Adina Racoviteanu5Department of Earth Science, University of Bergen, Bergen, NorwayDepartment of Geography, University of Bergen, Bergen, NorwayBjerknes Centre for Climate Research, Bergen, NorwayDepartment of Earth Science, University of Bergen, Bergen, NorwayBjerknes Centre for Climate Research, Bergen, NorwayInstitute of Environmental Geosciences (IGE), Grenoble, FranceEvaluating glacial change and the subsequent water stores in high mountains is becoming increasingly necessary, and in order to do this, models need reliable and consistent glacier data. These often come from global inventories, usually constructed from multi-temporal satellite imagery. However, there are limitations to these datasets. While clean ice can be mapped relatively easily using spectral band ratios, mapping debris-covered ice is more difficult due to the spectral similarity of supraglacial debris to the surrounding terrain. Therefore, analysts often employ manual delineation, a time-consuming and subjective approach to map debris-covered ice extents. Given the increasing prevalence of supraglacial debris in high mountain regions, such as High Mountain Asia, a systematic, objective approach is needed. The current study presents an approach for mapping debris-covered glaciers that integrates a convolutional neural network and object-based image analysis into one seamless classification workflow, applied to freely available and globally applicable Sentinel-2 multispectral, Landsat-8 thermal, Sentinel-1 interferometric coherence, and geomorphometric datasets. The approach is applied to three different domains in the Central Himalayan and the Karakoram ranges of High Mountain Asia that exhibit varying climatic regimes, topographies and debris-covered glacier characteristics. We evaluate the performance of the approach by comparison with a manually delineated glacier inventory, achieving F-score classification accuracies of 89.2%–93.7%. We also tested the performance of this approach on declassified panchromatic 1970 Corona KH-4B satellite imagery in the Manaslu region of Nepal, yielding accuracies of up to 88.4%. We find our approach to be robust, transferable to other regions, and accurate over regional (>4,000 km2) scales. Integrating object-based image analysis with deep-learning within a single workflow overcomes shortcomings associated with convolutional neural network classifications and permits a more flexible and robust approach for mapping debris-covered glaciers. The novel automated processing of panchromatic historical imagery, such as Corona KH-4B, opens the possibility of exploiting a wealth of multi-temporal data to understand past glacier changes.https://www.frontiersin.org/articles/10.3389/frsen.2023.1161530/fullconvolutional neural network (CNN)deep learningobject-based image analysis (OBIA)debris-covered glaciershistorical imageryHigh Mountain Asia
spellingShingle Daniel Jack Thomas
Daniel Jack Thomas
Daniel Jack Thomas
Benjamin Aubrey Robson
Benjamin Aubrey Robson
Adina Racoviteanu
An integrated deep learning and object-based image analysis approach for mapping debris-covered glaciers
Frontiers in Remote Sensing
convolutional neural network (CNN)
deep learning
object-based image analysis (OBIA)
debris-covered glaciers
historical imagery
High Mountain Asia
title An integrated deep learning and object-based image analysis approach for mapping debris-covered glaciers
title_full An integrated deep learning and object-based image analysis approach for mapping debris-covered glaciers
title_fullStr An integrated deep learning and object-based image analysis approach for mapping debris-covered glaciers
title_full_unstemmed An integrated deep learning and object-based image analysis approach for mapping debris-covered glaciers
title_short An integrated deep learning and object-based image analysis approach for mapping debris-covered glaciers
title_sort integrated deep learning and object based image analysis approach for mapping debris covered glaciers
topic convolutional neural network (CNN)
deep learning
object-based image analysis (OBIA)
debris-covered glaciers
historical imagery
High Mountain Asia
url https://www.frontiersin.org/articles/10.3389/frsen.2023.1161530/full
work_keys_str_mv AT danieljackthomas anintegrateddeeplearningandobjectbasedimageanalysisapproachformappingdebriscoveredglaciers
AT danieljackthomas anintegrateddeeplearningandobjectbasedimageanalysisapproachformappingdebriscoveredglaciers
AT danieljackthomas anintegrateddeeplearningandobjectbasedimageanalysisapproachformappingdebriscoveredglaciers
AT benjaminaubreyrobson anintegrateddeeplearningandobjectbasedimageanalysisapproachformappingdebriscoveredglaciers
AT benjaminaubreyrobson anintegrateddeeplearningandobjectbasedimageanalysisapproachformappingdebriscoveredglaciers
AT adinaracoviteanu anintegrateddeeplearningandobjectbasedimageanalysisapproachformappingdebriscoveredglaciers
AT danieljackthomas integrateddeeplearningandobjectbasedimageanalysisapproachformappingdebriscoveredglaciers
AT danieljackthomas integrateddeeplearningandobjectbasedimageanalysisapproachformappingdebriscoveredglaciers
AT danieljackthomas integrateddeeplearningandobjectbasedimageanalysisapproachformappingdebriscoveredglaciers
AT benjaminaubreyrobson integrateddeeplearningandobjectbasedimageanalysisapproachformappingdebriscoveredglaciers
AT benjaminaubreyrobson integrateddeeplearningandobjectbasedimageanalysisapproachformappingdebriscoveredglaciers
AT adinaracoviteanu integrateddeeplearningandobjectbasedimageanalysisapproachformappingdebriscoveredglaciers