Correlation between the specific surface area and the short wave infrared (SWIR) reflectance of snow
International audience The albedo of snow is determined in part by the size and shape of snow crystals, especially in the short wave infrared (SWIR). Many models of snow albedo represent snow crystals by spheres of surface/volume (S/V) ratio equal to that of snow crystals. However, the actual S/V ra...
Published in: | Cold Regions Science and Technology |
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Main Authors: | , , , , , |
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Format: | Article in Journal/Newspaper |
Language: | English |
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HAL CCSD
2006
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Online Access: | https://insu.hal.science/insu-00375443 https://doi.org/10.1016/j.coldregions.2006.06.002 |
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Institut national des sciences de l'Univers: HAL-INSU |
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English |
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Snow Specific surface area Albedo Reflectance Short wave infrared [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology |
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Snow Specific surface area Albedo Reflectance Short wave infrared [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology Domine, Florent Salvatori, Rosamaria Legagneux, Loic Salzano, Roberto Fily, Michel Casacchia, Ruggero Correlation between the specific surface area and the short wave infrared (SWIR) reflectance of snow |
topic_facet |
Snow Specific surface area Albedo Reflectance Short wave infrared [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology |
description |
International audience The albedo of snow is determined in part by the size and shape of snow crystals, especially in the short wave infrared (SWIR). Many models of snow albedo represent snow crystals by spheres of surface/volume (S/V) ratio equal to that of snow crystals. However, the actual S/V ratio of snow has never been measured simultaneously with the albedo, for a thorough test of models. Using CH4 adsorption at 77 K, we have measured the specific surface area (SSA) of snow samples, i.e. its ratio S/(V · ρ), where ρ is the density of ice, together with the snow spectral albedo using a field radiometer with nadir viewing, at Ny-Ålesund, Svalbard. Tests are performed at 1310, 1629, 1740 and 2260 nm, and we find a good correlation between the SSA and the snow spectral albedo in the SWIR (linear correlation coefficient R2 > 0.98 for the last 3 wavelengths). Snow samples having varied crystals shapes such as rounded crystals in windpacks and hollow faceted crystals in depth hoar were studied and crystal shape did not affect the correlation in a detectable manner. An interest in using SSA rather than crystal size to predict SWIR albedo is that the reflectance of large hollow crystals such as depth hoar or surface hoar will be correctly predicted from their SSA, while considering their large dimensions would underestimate reflectance. We compare these correlations to those predicted by commonly used optical models. The best agreement is found when we compare our data to the modeled hemispheric reflectance, corrected by an adjustable factor that shows a small wavelength dependence. We propose that, once these results have been confirmed by more studies, it may be possible to design a rapid and simple optical method to measure snow SSA in the field. Our results may also allow a more detailed use of remote sensing data to study snow metamorphism, air–snow exchanges of gases, and climate. |
author2 |
Laboratoire de glaciologie et géophysique de l'environnement (LGGE) Observatoire des Sciences de l'Univers de Grenoble (OSUG) Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Institute of Atmospheric Pollution Research (IIA) National Research Council of Italy |
format |
Article in Journal/Newspaper |
author |
Domine, Florent Salvatori, Rosamaria Legagneux, Loic Salzano, Roberto Fily, Michel Casacchia, Ruggero |
author_facet |
Domine, Florent Salvatori, Rosamaria Legagneux, Loic Salzano, Roberto Fily, Michel Casacchia, Ruggero |
author_sort |
Domine, Florent |
title |
Correlation between the specific surface area and the short wave infrared (SWIR) reflectance of snow |
title_short |
Correlation between the specific surface area and the short wave infrared (SWIR) reflectance of snow |
title_full |
Correlation between the specific surface area and the short wave infrared (SWIR) reflectance of snow |
title_fullStr |
Correlation between the specific surface area and the short wave infrared (SWIR) reflectance of snow |
title_full_unstemmed |
Correlation between the specific surface area and the short wave infrared (SWIR) reflectance of snow |
title_sort |
correlation between the specific surface area and the short wave infrared (swir) reflectance of snow |
publisher |
HAL CCSD |
publishDate |
2006 |
url |
https://insu.hal.science/insu-00375443 https://doi.org/10.1016/j.coldregions.2006.06.002 |
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Ny Ålesund Ny-Ålesund Svalbard |
genre_facet |
Ny Ålesund Ny-Ålesund Svalbard |
op_source |
ISSN: 0165-232X Cold Regions Science and Technology https://insu.hal.science/insu-00375443 Cold Regions Science and Technology, 2006, 46 (1), pp.60 à 68. ⟨10.1016/j.coldregions.2006.06.002⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.coldregions.2006.06.002 insu-00375443 https://insu.hal.science/insu-00375443 doi:10.1016/j.coldregions.2006.06.002 |
op_doi |
https://doi.org/10.1016/j.coldregions.2006.06.002 |
container_title |
Cold Regions Science and Technology |
container_volume |
46 |
container_issue |
1 |
container_start_page |
60 |
op_container_end_page |
68 |
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1797591064183308288 |
spelling |
ftinsu:oai:HAL:insu-00375443v1 2024-04-28T08:34:23+00:00 Correlation between the specific surface area and the short wave infrared (SWIR) reflectance of snow Domine, Florent Salvatori, Rosamaria Legagneux, Loic Salzano, Roberto Fily, Michel Casacchia, Ruggero Laboratoire de glaciologie et géophysique de l'environnement (LGGE) Observatoire des Sciences de l'Univers de Grenoble (OSUG) Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Institute of Atmospheric Pollution Research (IIA) National Research Council of Italy 2006 https://insu.hal.science/insu-00375443 https://doi.org/10.1016/j.coldregions.2006.06.002 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.coldregions.2006.06.002 insu-00375443 https://insu.hal.science/insu-00375443 doi:10.1016/j.coldregions.2006.06.002 ISSN: 0165-232X Cold Regions Science and Technology https://insu.hal.science/insu-00375443 Cold Regions Science and Technology, 2006, 46 (1), pp.60 à 68. ⟨10.1016/j.coldregions.2006.06.002⟩ Snow Specific surface area Albedo Reflectance Short wave infrared [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology info:eu-repo/semantics/article Journal articles 2006 ftinsu https://doi.org/10.1016/j.coldregions.2006.06.002 2024-04-05T00:31:43Z International audience The albedo of snow is determined in part by the size and shape of snow crystals, especially in the short wave infrared (SWIR). Many models of snow albedo represent snow crystals by spheres of surface/volume (S/V) ratio equal to that of snow crystals. However, the actual S/V ratio of snow has never been measured simultaneously with the albedo, for a thorough test of models. Using CH4 adsorption at 77 K, we have measured the specific surface area (SSA) of snow samples, i.e. its ratio S/(V · ρ), where ρ is the density of ice, together with the snow spectral albedo using a field radiometer with nadir viewing, at Ny-Ålesund, Svalbard. Tests are performed at 1310, 1629, 1740 and 2260 nm, and we find a good correlation between the SSA and the snow spectral albedo in the SWIR (linear correlation coefficient R2 > 0.98 for the last 3 wavelengths). Snow samples having varied crystals shapes such as rounded crystals in windpacks and hollow faceted crystals in depth hoar were studied and crystal shape did not affect the correlation in a detectable manner. An interest in using SSA rather than crystal size to predict SWIR albedo is that the reflectance of large hollow crystals such as depth hoar or surface hoar will be correctly predicted from their SSA, while considering their large dimensions would underestimate reflectance. We compare these correlations to those predicted by commonly used optical models. The best agreement is found when we compare our data to the modeled hemispheric reflectance, corrected by an adjustable factor that shows a small wavelength dependence. We propose that, once these results have been confirmed by more studies, it may be possible to design a rapid and simple optical method to measure snow SSA in the field. Our results may also allow a more detailed use of remote sensing data to study snow metamorphism, air–snow exchanges of gases, and climate. Article in Journal/Newspaper Ny Ålesund Ny-Ålesund Svalbard Institut national des sciences de l'Univers: HAL-INSU Cold Regions Science and Technology 46 1 60 68 |