Video3_What Can Thermal Imagery Tell Us About Glacier Melt Below Rock Debris?.MP4
Rock debris on the surface of a glacier can dramatically reduce the local melt rate, where the primary factor governing melt reduction is debris layer thickness. Relating surface temperature to debris thickness is a recurring approach in the literature, yet demonstrations of reproducibility have bee...
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ftfrontimediafig:oai:figshare.com:article/16532598 2023-05-15T16:20:38+02:00 Video3_What Can Thermal Imagery Tell Us About Glacier Melt Below Rock Debris?.MP4 Sam Herreid 2021-08-30T05:40:15Z https://doi.org/10.3389/feart.2021.681059.s004 https://figshare.com/articles/media/Video3_What_Can_Thermal_Imagery_Tell_Us_About_Glacier_Melt_Below_Rock_Debris_MP4/16532598 unknown doi:10.3389/feart.2021.681059.s004 https://figshare.com/articles/media/Video3_What_Can_Thermal_Imagery_Tell_Us_About_Glacier_Melt_Below_Rock_Debris_MP4/16532598 CC BY 4.0 CC-BY Solid Earth Sciences Climate Science Atmospheric Sciences not elsewhere classified Exploration Geochemistry Inorganic Geochemistry Isotope Geochemistry Organic Geochemistry Geochemistry not elsewhere classified Igneous and Metamorphic Petrology Ore Deposit Petrology Palaeontology (incl. Palynology) Structural Geology Tectonics Volcanology Geology not elsewhere classified Seismology and Seismic Exploration Glaciology Hydrogeology Natural Hazards Quaternary Environments Earth Sciences not elsewhere classified Evolutionary Impacts of Climate Change thermal infrared glacier melt modeling ASTER thermal infrared debris covered glaciers cryosphere mountain glaciers thermal image processing Dataset Media 2021 ftfrontimediafig https://doi.org/10.3389/feart.2021.681059.s004 2021-09-01T23:00:00Z Rock debris on the surface of a glacier can dramatically reduce the local melt rate, where the primary factor governing melt reduction is debris layer thickness. Relating surface temperature to debris thickness is a recurring approach in the literature, yet demonstrations of reproducibility have been limited. Here, I present the results of a field experiment conducted on the Canwell Glacier, Alaska, United States to constrain how thermal data can be used in glaciology. These datasets include, 1) a measured sub-daily “Østrem curve” time-series; 2) a time-series of high resolution thermal images capturing several segments of different debris thicknesses including the measurements from 1); 3) a thermal profile through a 38 cm debris cover; and 4) two Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite thermal images acquired within 2 and 3 min of a field-based thermal camera image. I show that, while clear sky conditions are when space-borne thermal sensors can image a glacier, this is an unfavorable time, limiting the likelihood that different thicknesses of debris will have a unique thermal signature. I then propose an empirical approach to estimate debris thickness and compare it to two recently published methods. I demonstrate that instantaneous calibration is essential in the previously published methods, where model parameters calibrated only 1 h prior to a repeat thermal image return diminished debris thickness estimates, while the method proposed here remains robust through time and does not appear to require re-calibration. I then propose a method that uses a time-series of surface temperature at one location and debris thickness to estimate bare-ice and sub-debris melt. Results show comparable cumulative melt estimates to a recently published method that requires an explicit/external estimate of bare ice melt. Finally, I show that sub-pixel corrections to ASTER thermal imagery can enable a close resemblance to high resolution, field-based thermal imagery. These results offer a ... Dataset glacier glaciers Alaska Frontiers: Figshare Østrem ENVELOPE(8.681,8.681,63.387,63.387) |
institution |
Open Polar |
collection |
Frontiers: Figshare |
op_collection_id |
ftfrontimediafig |
language |
unknown |
topic |
Solid Earth Sciences Climate Science Atmospheric Sciences not elsewhere classified Exploration Geochemistry Inorganic Geochemistry Isotope Geochemistry Organic Geochemistry Geochemistry not elsewhere classified Igneous and Metamorphic Petrology Ore Deposit Petrology Palaeontology (incl. Palynology) Structural Geology Tectonics Volcanology Geology not elsewhere classified Seismology and Seismic Exploration Glaciology Hydrogeology Natural Hazards Quaternary Environments Earth Sciences not elsewhere classified Evolutionary Impacts of Climate Change thermal infrared glacier melt modeling ASTER thermal infrared debris covered glaciers cryosphere mountain glaciers thermal image processing |
spellingShingle |
Solid Earth Sciences Climate Science Atmospheric Sciences not elsewhere classified Exploration Geochemistry Inorganic Geochemistry Isotope Geochemistry Organic Geochemistry Geochemistry not elsewhere classified Igneous and Metamorphic Petrology Ore Deposit Petrology Palaeontology (incl. Palynology) Structural Geology Tectonics Volcanology Geology not elsewhere classified Seismology and Seismic Exploration Glaciology Hydrogeology Natural Hazards Quaternary Environments Earth Sciences not elsewhere classified Evolutionary Impacts of Climate Change thermal infrared glacier melt modeling ASTER thermal infrared debris covered glaciers cryosphere mountain glaciers thermal image processing Sam Herreid Video3_What Can Thermal Imagery Tell Us About Glacier Melt Below Rock Debris?.MP4 |
topic_facet |
Solid Earth Sciences Climate Science Atmospheric Sciences not elsewhere classified Exploration Geochemistry Inorganic Geochemistry Isotope Geochemistry Organic Geochemistry Geochemistry not elsewhere classified Igneous and Metamorphic Petrology Ore Deposit Petrology Palaeontology (incl. Palynology) Structural Geology Tectonics Volcanology Geology not elsewhere classified Seismology and Seismic Exploration Glaciology Hydrogeology Natural Hazards Quaternary Environments Earth Sciences not elsewhere classified Evolutionary Impacts of Climate Change thermal infrared glacier melt modeling ASTER thermal infrared debris covered glaciers cryosphere mountain glaciers thermal image processing |
description |
Rock debris on the surface of a glacier can dramatically reduce the local melt rate, where the primary factor governing melt reduction is debris layer thickness. Relating surface temperature to debris thickness is a recurring approach in the literature, yet demonstrations of reproducibility have been limited. Here, I present the results of a field experiment conducted on the Canwell Glacier, Alaska, United States to constrain how thermal data can be used in glaciology. These datasets include, 1) a measured sub-daily “Østrem curve” time-series; 2) a time-series of high resolution thermal images capturing several segments of different debris thicknesses including the measurements from 1); 3) a thermal profile through a 38 cm debris cover; and 4) two Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite thermal images acquired within 2 and 3 min of a field-based thermal camera image. I show that, while clear sky conditions are when space-borne thermal sensors can image a glacier, this is an unfavorable time, limiting the likelihood that different thicknesses of debris will have a unique thermal signature. I then propose an empirical approach to estimate debris thickness and compare it to two recently published methods. I demonstrate that instantaneous calibration is essential in the previously published methods, where model parameters calibrated only 1 h prior to a repeat thermal image return diminished debris thickness estimates, while the method proposed here remains robust through time and does not appear to require re-calibration. I then propose a method that uses a time-series of surface temperature at one location and debris thickness to estimate bare-ice and sub-debris melt. Results show comparable cumulative melt estimates to a recently published method that requires an explicit/external estimate of bare ice melt. Finally, I show that sub-pixel corrections to ASTER thermal imagery can enable a close resemblance to high resolution, field-based thermal imagery. These results offer a ... |
format |
Dataset |
author |
Sam Herreid |
author_facet |
Sam Herreid |
author_sort |
Sam Herreid |
title |
Video3_What Can Thermal Imagery Tell Us About Glacier Melt Below Rock Debris?.MP4 |
title_short |
Video3_What Can Thermal Imagery Tell Us About Glacier Melt Below Rock Debris?.MP4 |
title_full |
Video3_What Can Thermal Imagery Tell Us About Glacier Melt Below Rock Debris?.MP4 |
title_fullStr |
Video3_What Can Thermal Imagery Tell Us About Glacier Melt Below Rock Debris?.MP4 |
title_full_unstemmed |
Video3_What Can Thermal Imagery Tell Us About Glacier Melt Below Rock Debris?.MP4 |
title_sort |
video3_what can thermal imagery tell us about glacier melt below rock debris?.mp4 |
publishDate |
2021 |
url |
https://doi.org/10.3389/feart.2021.681059.s004 https://figshare.com/articles/media/Video3_What_Can_Thermal_Imagery_Tell_Us_About_Glacier_Melt_Below_Rock_Debris_MP4/16532598 |
long_lat |
ENVELOPE(8.681,8.681,63.387,63.387) |
geographic |
Østrem |
geographic_facet |
Østrem |
genre |
glacier glaciers Alaska |
genre_facet |
glacier glaciers Alaska |
op_relation |
doi:10.3389/feart.2021.681059.s004 https://figshare.com/articles/media/Video3_What_Can_Thermal_Imagery_Tell_Us_About_Glacier_Melt_Below_Rock_Debris_MP4/16532598 |
op_rights |
CC BY 4.0 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.3389/feart.2021.681059.s004 |
_version_ |
1766008563580272640 |