Vertical structure of Arctic haze observed by lidar
In the study of the Arctic Haze phenomenon, understanding the vertical structure of the haze aerosol is crucial in defining mechanisms of haze transport. Questions have also arisen concerning the representativeness of surface observations of Arctic Haze. Due to the strongly stratified nature of the...
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ftnasantrs:oai:casi.ntrs.nasa.gov:19870000902 2023-05-15T14:51:09+02:00 Vertical structure of Arctic haze observed by lidar Hoff, R. M. Unclassified, Unlimited, Publicly available Aug 1, 1986 application/pdf http://hdl.handle.net/2060/19870000902 unknown Document ID: 19870000902 Accession ID: 87N10335 http://hdl.handle.net/2060/19870000902 No Copyright CASI METEOROLOGY AND CLIMATOLOGY NASA. Langley Research Center 13th International Laser Radar Conference; 3 p 1986 ftnasantrs 2016-06-11T22:51:55Z In the study of the Arctic Haze phenomenon, understanding the vertical structure of the haze aerosol is crucial in defining mechanisms of haze transport. Questions have also arisen concerning the representativeness of surface observations of Arctic Haze. Due to the strongly stratified nature of the Arctic troposphere, the mechanisms which transport aerosol to the surface from the transport altitudes of the lower troposphere are not obvious. In order to examine these questions, a Mie scattering lidar was installed at Alert, NWT, Canada. Lidar observes atmospheric aerosols and hydrymeteors as they appear in nature, unmodified by sampling effects. As such the results obtained are more realistic of the light scattering characteristics of the in situ aerosol than are those obtained by integrating nephelometers, for example, which heat the aerosol and dry it before measurement. With this lidar, a pulse was transmitted vetically through an evacuated tube in the roof of a building at Alert. The receiver consisted of a 20cm diameter Fresnel telescope, neutral density and polarizing filters, and RCA C31000A PMT, Analog Modules LA-90-P logarithmic amplifier and a Lecroy TR8827 32 MHz digitizer. The lidar equation was solved for the backscattering coefficient of the aerosol assuming no two way transmission losses in the signal. The lidar results have shown that intercomparison between lidar obtained visibilities and observer visibilities are in much better agreement than for other optical or aerosol monitors. Three new effects were identified in the lidar profiles which contribute to the vertical transport of haze. These effects are briefly discussed. Other/Unknown Material Arctic NASA Technical Reports Server (NTRS) Arctic Canada |
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Open Polar |
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NASA Technical Reports Server (NTRS) |
op_collection_id |
ftnasantrs |
language |
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topic |
METEOROLOGY AND CLIMATOLOGY |
spellingShingle |
METEOROLOGY AND CLIMATOLOGY Hoff, R. M. Vertical structure of Arctic haze observed by lidar |
topic_facet |
METEOROLOGY AND CLIMATOLOGY |
description |
In the study of the Arctic Haze phenomenon, understanding the vertical structure of the haze aerosol is crucial in defining mechanisms of haze transport. Questions have also arisen concerning the representativeness of surface observations of Arctic Haze. Due to the strongly stratified nature of the Arctic troposphere, the mechanisms which transport aerosol to the surface from the transport altitudes of the lower troposphere are not obvious. In order to examine these questions, a Mie scattering lidar was installed at Alert, NWT, Canada. Lidar observes atmospheric aerosols and hydrymeteors as they appear in nature, unmodified by sampling effects. As such the results obtained are more realistic of the light scattering characteristics of the in situ aerosol than are those obtained by integrating nephelometers, for example, which heat the aerosol and dry it before measurement. With this lidar, a pulse was transmitted vetically through an evacuated tube in the roof of a building at Alert. The receiver consisted of a 20cm diameter Fresnel telescope, neutral density and polarizing filters, and RCA C31000A PMT, Analog Modules LA-90-P logarithmic amplifier and a Lecroy TR8827 32 MHz digitizer. The lidar equation was solved for the backscattering coefficient of the aerosol assuming no two way transmission losses in the signal. The lidar results have shown that intercomparison between lidar obtained visibilities and observer visibilities are in much better agreement than for other optical or aerosol monitors. Three new effects were identified in the lidar profiles which contribute to the vertical transport of haze. These effects are briefly discussed. |
format |
Other/Unknown Material |
author |
Hoff, R. M. |
author_facet |
Hoff, R. M. |
author_sort |
Hoff, R. M. |
title |
Vertical structure of Arctic haze observed by lidar |
title_short |
Vertical structure of Arctic haze observed by lidar |
title_full |
Vertical structure of Arctic haze observed by lidar |
title_fullStr |
Vertical structure of Arctic haze observed by lidar |
title_full_unstemmed |
Vertical structure of Arctic haze observed by lidar |
title_sort |
vertical structure of arctic haze observed by lidar |
publishDate |
1986 |
url |
http://hdl.handle.net/2060/19870000902 |
op_coverage |
Unclassified, Unlimited, Publicly available |
geographic |
Arctic Canada |
geographic_facet |
Arctic Canada |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
CASI |
op_relation |
Document ID: 19870000902 Accession ID: 87N10335 http://hdl.handle.net/2060/19870000902 |
op_rights |
No Copyright |
_version_ |
1766322217519415296 |