An objective technique for Arctic cloud analysis using multispectral AVHRR satellite imagery
An established cloud analysis routine has been modified for use in the Arctic. The separation of clouds from the snow and sea ice backgrounds is accomplished through a multispectral technique which utilizes VHRR channel 2 (visible), channel 3 (near infrared) and channel 4 (infrared) data. The primar...
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Monterey, California. Naval Postgraduate School
1988
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ftnavalpschool:oai:calhoun.nps.edu:10945/23335 2024-06-09T07:43:26+00:00 An objective technique for Arctic cloud analysis using multispectral AVHRR satellite imagery Barron, John P. Durkee, Philip A. Wash, Carlyle H. 1988-03 80 p. application/pdf https://hdl.handle.net/10945/23335 en_US eng Monterey, California. Naval Postgraduate School https://hdl.handle.net/10945/23335 This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States. arctic cloud analysis AVHRR channel 3 snow/cloud discrimination Meteorology Thesis 1988 ftnavalpschool 2024-05-15T00:18:56Z An established cloud analysis routine has been modified for use in the Arctic. The separation of clouds from the snow and sea ice backgrounds is accomplished through a multispectral technique which utilizes VHRR channel 2 (visible), channel 3 (near infrared) and channel 4 (infrared) data. The primary means of cloud identification is based on a derived channel 3 reflectance image. At this wavelength, a significant contrast exists between liquid clouds and the arctic backgrounds, unlike in the standard visible and infrared images. The channel 3 reflectance is obtained by first using the channel 4 emission temperature to estimate the thermal emission component of the total channel 3 radiance. This thermal emission component is subsequently removed from the total radiance, leaving only the solar reflectance component available for analysis. Since many ice clouds do not exhibit a substantially greater reflectance is channel 3, the routine exploits differences in transmissive characteristics between channels 3 and 4 for identification. The routine was applied to six case studies which had been analyzed by three independent experts to establish 'ground truth'. Verification of the cloud analysis results, through a comparison to the subjective analyses, yielded impressive statistics. A success rate of 77.9% was obtained with an arguably small data base of 131 undisputed scenes Approved for public release; distribution is unlimited. Lieutenant, United States Navy http://archive.org/details/anobjectivetechn1094523335 Thesis Arctic Sea ice Naval Postgraduate School: Calhoun Arctic |
institution |
Open Polar |
collection |
Naval Postgraduate School: Calhoun |
op_collection_id |
ftnavalpschool |
language |
English |
topic |
arctic cloud analysis AVHRR channel 3 snow/cloud discrimination Meteorology |
spellingShingle |
arctic cloud analysis AVHRR channel 3 snow/cloud discrimination Meteorology Barron, John P. An objective technique for Arctic cloud analysis using multispectral AVHRR satellite imagery |
topic_facet |
arctic cloud analysis AVHRR channel 3 snow/cloud discrimination Meteorology |
description |
An established cloud analysis routine has been modified for use in the Arctic. The separation of clouds from the snow and sea ice backgrounds is accomplished through a multispectral technique which utilizes VHRR channel 2 (visible), channel 3 (near infrared) and channel 4 (infrared) data. The primary means of cloud identification is based on a derived channel 3 reflectance image. At this wavelength, a significant contrast exists between liquid clouds and the arctic backgrounds, unlike in the standard visible and infrared images. The channel 3 reflectance is obtained by first using the channel 4 emission temperature to estimate the thermal emission component of the total channel 3 radiance. This thermal emission component is subsequently removed from the total radiance, leaving only the solar reflectance component available for analysis. Since many ice clouds do not exhibit a substantially greater reflectance is channel 3, the routine exploits differences in transmissive characteristics between channels 3 and 4 for identification. The routine was applied to six case studies which had been analyzed by three independent experts to establish 'ground truth'. Verification of the cloud analysis results, through a comparison to the subjective analyses, yielded impressive statistics. A success rate of 77.9% was obtained with an arguably small data base of 131 undisputed scenes Approved for public release; distribution is unlimited. Lieutenant, United States Navy http://archive.org/details/anobjectivetechn1094523335 |
author2 |
Durkee, Philip A. Wash, Carlyle H. |
format |
Thesis |
author |
Barron, John P. |
author_facet |
Barron, John P. |
author_sort |
Barron, John P. |
title |
An objective technique for Arctic cloud analysis using multispectral AVHRR satellite imagery |
title_short |
An objective technique for Arctic cloud analysis using multispectral AVHRR satellite imagery |
title_full |
An objective technique for Arctic cloud analysis using multispectral AVHRR satellite imagery |
title_fullStr |
An objective technique for Arctic cloud analysis using multispectral AVHRR satellite imagery |
title_full_unstemmed |
An objective technique for Arctic cloud analysis using multispectral AVHRR satellite imagery |
title_sort |
objective technique for arctic cloud analysis using multispectral avhrr satellite imagery |
publisher |
Monterey, California. Naval Postgraduate School |
publishDate |
1988 |
url |
https://hdl.handle.net/10945/23335 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Sea ice |
genre_facet |
Arctic Sea ice |
op_relation |
https://hdl.handle.net/10945/23335 |
op_rights |
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States. |
_version_ |
1801372203554439168 |