Spectral measurements of surface hoar crystals
Surface hoar crystals are common on the surface of mountain snow covers. Once buried, layers of large plate-shaped surface hoar crystals are prone to releasing dangerous snow-slab avalanches. Since snow microstructure influences the optical properties of snow, remote sensors could potentially detect...
Main Authors: | , |
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Format: | Article |
Language: | English |
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Cambridge University Press
2017-06-01
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Series: | Journal of Glaciology |
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Online Access: | https://www.cambridge.org/core/product/identifier/S0022143017000065/type/journal_article |
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author | SIMON HORTON BRUCE JAMIESON |
author_facet | SIMON HORTON BRUCE JAMIESON |
author_sort | SIMON HORTON |
collection | DOAJ |
description | Surface hoar crystals are common on the surface of mountain snow covers. Once buried, layers of large plate-shaped surface hoar crystals are prone to releasing dangerous snow-slab avalanches. Since snow microstructure influences the optical properties of snow, remote sensors could potentially detect the formation of surface hoar and other snow types associated with avalanche release. The spectral reflectance of 377 snow samples was measured with a field spectrometer between 750 and 2500 nm, including 161 samples of surface hoar. Morphological snow shapes associated with critical avalanche layers (surface hoar, near-surface faceted particles and depth hoar) had lower average reflectance factors than non-critical snow shapes at infrared wavelengths. Needle-shaped surface hoar was more reflective than plate-shaped surface hoar, but there were no significant differences between different sizes of surface hoar. Normalized difference indices calculated with reflectance from two wavelength bands is presented as a potential method to classify critical snow surfaces remotely, although melt-freeze crusts near the surface complicated the classification. Accordingly, further studying on the effect of melt-freeze crusts and quantification of the bidirectional reflective properties of critical snow types is needed. |
first_indexed | 2024-04-10T04:42:13Z |
format | Article |
id | doaj.art-cf73857f4ec2429280bf513227a9bb1d |
institution | Directory Open Access Journal |
issn | 0022-1430 1727-5652 |
language | English |
last_indexed | 2024-04-10T04:42:13Z |
publishDate | 2017-06-01 |
publisher | Cambridge University Press |
record_format | Article |
series | Journal of Glaciology |
spelling | doaj.art-cf73857f4ec2429280bf513227a9bb1d2023-03-09T12:40:23ZengCambridge University PressJournal of Glaciology0022-14301727-56522017-06-016347748610.1017/jog.2017.6Spectral measurements of surface hoar crystalsSIMON HORTON0https://orcid.org/0000-0003-2936-8688BRUCE JAMIESON1Department of Civil Engineering, University of Calgary, Calgary, Alberta, T2N 1N4, CanadaDepartment of Civil Engineering, University of Calgary, Calgary, Alberta, T2N 1N4, CanadaSurface hoar crystals are common on the surface of mountain snow covers. Once buried, layers of large plate-shaped surface hoar crystals are prone to releasing dangerous snow-slab avalanches. Since snow microstructure influences the optical properties of snow, remote sensors could potentially detect the formation of surface hoar and other snow types associated with avalanche release. The spectral reflectance of 377 snow samples was measured with a field spectrometer between 750 and 2500 nm, including 161 samples of surface hoar. Morphological snow shapes associated with critical avalanche layers (surface hoar, near-surface faceted particles and depth hoar) had lower average reflectance factors than non-critical snow shapes at infrared wavelengths. Needle-shaped surface hoar was more reflective than plate-shaped surface hoar, but there were no significant differences between different sizes of surface hoar. Normalized difference indices calculated with reflectance from two wavelength bands is presented as a potential method to classify critical snow surfaces remotely, although melt-freeze crusts near the surface complicated the classification. Accordingly, further studying on the effect of melt-freeze crusts and quantification of the bidirectional reflective properties of critical snow types is needed.https://www.cambridge.org/core/product/identifier/S0022143017000065/type/journal_articleavalanchesfrostremote sensingsnow |
spellingShingle | SIMON HORTON BRUCE JAMIESON Spectral measurements of surface hoar crystals Journal of Glaciology avalanches frost remote sensing snow |
title | Spectral measurements of surface hoar crystals |
title_full | Spectral measurements of surface hoar crystals |
title_fullStr | Spectral measurements of surface hoar crystals |
title_full_unstemmed | Spectral measurements of surface hoar crystals |
title_short | Spectral measurements of surface hoar crystals |
title_sort | spectral measurements of surface hoar crystals |
topic | avalanches frost remote sensing snow |
url | https://www.cambridge.org/core/product/identifier/S0022143017000065/type/journal_article |
work_keys_str_mv | AT simonhorton spectralmeasurementsofsurfacehoarcrystals AT brucejamieson spectralmeasurementsofsurfacehoarcrystals |