Laboratory Studies of the Optical Properties of Young Sea Ice
Abstract Laboratory experiments were performed to determine the optical properties of young salt ice and to examine correlations between the optical properties and the state of the ice. Ice was grown at different temperatures (–10, –20, –30, and –37°C) from water of different salinities (0, 16, and...
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Cambridge University Press (CUP)
1981
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Online Access: | http://dx.doi.org/10.1017/s0022143000015410 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000015410 |
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crcambridgeupr:10.1017/s0022143000015410 2024-03-03T08:46:09+00:00 Laboratory Studies of the Optical Properties of Young Sea Ice Perovich, Donald K. Grenfell, Thomas C. 1981 http://dx.doi.org/10.1017/s0022143000015410 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000015410 en eng Cambridge University Press (CUP) Journal of Glaciology volume 27, issue 96, page 331-346 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 1981 crcambridgeupr https://doi.org/10.1017/s0022143000015410 2024-02-08T08:40:37Z Abstract Laboratory experiments were performed to determine the optical properties of young salt ice and to examine correlations between the optical properties and the state of the ice. Ice was grown at different temperatures (–10, –20, –30, and –37°C) from water of different salinities (0, 16, and 31‰). The experiments were conducted in a cylindrical tank 1 m in diameter designed to approximate natural ice growth and to permit in situ optical measurements. Observed incident, reflected, and transmitted irradiances were used in conjunction with a modified Dunkle and Bevans photometric model to determine spectral albedos and extinction coefficients. Cold ice only 0.25 m thick had albedos which were comparable to the values for 2 to 3 m multi-year ice examined by previous researchers during the summer melt season; extinction coefficients were 1.5 to 15 times greater. As the ice temperature and hence brine volume decreased, both albedo and extinction coefficient increased; when the ice temperature dropped below the eutectic point, they increased sharply. In addition, ice grown at lower air temperatures had greater albedos and extinction coefficients even when ice temperatures were the same. Variations in the optical properties of the ice are determined by changes in the amount of brine and its distribution; thus the optical properties of salt ice depend not only on ice temperature but on initial growth rate. Variations in ice salinity over the range 4‰ to 14‰ produced no detectable changes in the optical properties. Article in Journal/Newspaper Journal of Glaciology Sea ice Cambridge University Press Journal of Glaciology 27 96 331 346 |
institution |
Open Polar |
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Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
spellingShingle |
Earth-Surface Processes Perovich, Donald K. Grenfell, Thomas C. Laboratory Studies of the Optical Properties of Young Sea Ice |
topic_facet |
Earth-Surface Processes |
description |
Abstract Laboratory experiments were performed to determine the optical properties of young salt ice and to examine correlations between the optical properties and the state of the ice. Ice was grown at different temperatures (–10, –20, –30, and –37°C) from water of different salinities (0, 16, and 31‰). The experiments were conducted in a cylindrical tank 1 m in diameter designed to approximate natural ice growth and to permit in situ optical measurements. Observed incident, reflected, and transmitted irradiances were used in conjunction with a modified Dunkle and Bevans photometric model to determine spectral albedos and extinction coefficients. Cold ice only 0.25 m thick had albedos which were comparable to the values for 2 to 3 m multi-year ice examined by previous researchers during the summer melt season; extinction coefficients were 1.5 to 15 times greater. As the ice temperature and hence brine volume decreased, both albedo and extinction coefficient increased; when the ice temperature dropped below the eutectic point, they increased sharply. In addition, ice grown at lower air temperatures had greater albedos and extinction coefficients even when ice temperatures were the same. Variations in the optical properties of the ice are determined by changes in the amount of brine and its distribution; thus the optical properties of salt ice depend not only on ice temperature but on initial growth rate. Variations in ice salinity over the range 4‰ to 14‰ produced no detectable changes in the optical properties. |
format |
Article in Journal/Newspaper |
author |
Perovich, Donald K. Grenfell, Thomas C. |
author_facet |
Perovich, Donald K. Grenfell, Thomas C. |
author_sort |
Perovich, Donald K. |
title |
Laboratory Studies of the Optical Properties of Young Sea Ice |
title_short |
Laboratory Studies of the Optical Properties of Young Sea Ice |
title_full |
Laboratory Studies of the Optical Properties of Young Sea Ice |
title_fullStr |
Laboratory Studies of the Optical Properties of Young Sea Ice |
title_full_unstemmed |
Laboratory Studies of the Optical Properties of Young Sea Ice |
title_sort |
laboratory studies of the optical properties of young sea ice |
publisher |
Cambridge University Press (CUP) |
publishDate |
1981 |
url |
http://dx.doi.org/10.1017/s0022143000015410 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000015410 |
genre |
Journal of Glaciology Sea ice |
genre_facet |
Journal of Glaciology Sea ice |
op_source |
Journal of Glaciology volume 27, issue 96, page 331-346 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000015410 |
container_title |
Journal of Glaciology |
container_volume |
27 |
container_issue |
96 |
container_start_page |
331 |
op_container_end_page |
346 |
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1792502131744309248 |