Atmospheric visibility inferred from continuous-wave Doppler wind lidar
<p>Atmospheric visibility, or meteorological optical range (MOR), is governed by light extinction by aerosols. State-of-the-art visibility sensors, such as employed in meteorological observatories and airports, infer MOR by measuring either transmittance or scattering. While these sensors yiel...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2022-09-01
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| Series: | Atmospheric Measurement Techniques |
| Online Access: | https://amt.copernicus.org/articles/15/5527/2022/amt-15-5527-2022.pdf |
| _version_ | 1798000215513366528 |
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| author | M. Queißer M. Harris S. Knoop |
| author_facet | M. Queißer M. Harris S. Knoop |
| author_sort | M. Queißer |
| collection | DOAJ |
| description | <p>Atmospheric visibility, or meteorological optical range
(MOR), is governed by light extinction by aerosols. State-of-the-art
visibility sensors, such as employed in meteorological observatories and
airports, infer MOR by measuring either transmittance or scattering. While
these sensors yield robust measurements with reasonable accuracy (10 % to 20 %), they measure in situ. MOR from these sensors may thus not be
representative of MOR further away, for example, under conditions with
stratified aerosol types. This includes off-shore sites near the sea surface during conditions with advection fog, sea spray or mist. Elastic backscatter lidar can be used to measure light extinction and has previously
demonstrated to be a powerful method to infer visibility. Lidar can measure
visibility not just near the instrument but also further away (remotely) and
single-ended whilst also being capable of measuring profiles of MOR along atmospheric
slant paths. Continuous-wave (CW) Doppler wind lidar systems make up one of
the most widespread type of elastic backscatter lidar and are typically used in wind resource assessment. Using these existing platforms for remote and single-ended measurement of MOR profiles could allow for new and valuable applications. However, the low-light extinction associated with this type of
lidar excludes the use of the extinction coefficient for MOR retrieval but
leaves the backscatter coefficient as a possible proxy for MOR, though with
an accuracy expected to be inferior to the former method. We analysed
backscatter data from CW wind lidar and co-measured MOR from visibility
sensors from two campaigns (Cabauw, Netherlands, and Pershore, United
Kingdom) and found backscatter from CW wind lidar to be a viable proxy of
MOR if calibrated against a visibility sensor. The expected accuracy of the
method is low and of the order of few kilometres. This means MOR from CW wind
lidar could be used in safety-uncritical problems, such as assessment of
visibility of manmade objects, including wind turbines.</p> |
| first_indexed | 2024-04-11T11:16:38Z |
| format | Article |
| id | doaj.art-e4383c1d206641558fe9d72080a41885 |
| institution | Directory Open Access Journal |
| issn | 1867-1381 1867-8548 |
| language | English |
| last_indexed | 2024-04-11T11:16:38Z |
| publishDate | 2022-09-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Measurement Techniques |
| spelling | doaj.art-e4383c1d206641558fe9d72080a418852022-12-22T04:27:11ZengCopernicus PublicationsAtmospheric Measurement Techniques1867-13811867-85482022-09-01155527554410.5194/amt-15-5527-2022Atmospheric visibility inferred from continuous-wave Doppler wind lidarM. Queißer0M. Harris1S. Knoop2ZX Lidars, The Old Barns, Fairoaks Farm, Hollybush, Ledbury, HR8 1EU, UKZX Lidars, The Old Barns, Fairoaks Farm, Hollybush, Ledbury, HR8 1EU, UKRoyal Netherlands Meteorological Institute (KNMI), Utrechtseweg 297, 3731 GA, De Bilt, the Netherlands<p>Atmospheric visibility, or meteorological optical range (MOR), is governed by light extinction by aerosols. State-of-the-art visibility sensors, such as employed in meteorological observatories and airports, infer MOR by measuring either transmittance or scattering. While these sensors yield robust measurements with reasonable accuracy (10 % to 20 %), they measure in situ. MOR from these sensors may thus not be representative of MOR further away, for example, under conditions with stratified aerosol types. This includes off-shore sites near the sea surface during conditions with advection fog, sea spray or mist. Elastic backscatter lidar can be used to measure light extinction and has previously demonstrated to be a powerful method to infer visibility. Lidar can measure visibility not just near the instrument but also further away (remotely) and single-ended whilst also being capable of measuring profiles of MOR along atmospheric slant paths. Continuous-wave (CW) Doppler wind lidar systems make up one of the most widespread type of elastic backscatter lidar and are typically used in wind resource assessment. Using these existing platforms for remote and single-ended measurement of MOR profiles could allow for new and valuable applications. However, the low-light extinction associated with this type of lidar excludes the use of the extinction coefficient for MOR retrieval but leaves the backscatter coefficient as a possible proxy for MOR, though with an accuracy expected to be inferior to the former method. We analysed backscatter data from CW wind lidar and co-measured MOR from visibility sensors from two campaigns (Cabauw, Netherlands, and Pershore, United Kingdom) and found backscatter from CW wind lidar to be a viable proxy of MOR if calibrated against a visibility sensor. The expected accuracy of the method is low and of the order of few kilometres. This means MOR from CW wind lidar could be used in safety-uncritical problems, such as assessment of visibility of manmade objects, including wind turbines.</p>https://amt.copernicus.org/articles/15/5527/2022/amt-15-5527-2022.pdf |
| spellingShingle | M. Queißer M. Harris S. Knoop Atmospheric visibility inferred from continuous-wave Doppler wind lidar Atmospheric Measurement Techniques |
| title | Atmospheric visibility inferred from continuous-wave Doppler wind lidar |
| title_full | Atmospheric visibility inferred from continuous-wave Doppler wind lidar |
| title_fullStr | Atmospheric visibility inferred from continuous-wave Doppler wind lidar |
| title_full_unstemmed | Atmospheric visibility inferred from continuous-wave Doppler wind lidar |
| title_short | Atmospheric visibility inferred from continuous-wave Doppler wind lidar |
| title_sort | atmospheric visibility inferred from continuous wave doppler wind lidar |
| url | https://amt.copernicus.org/articles/15/5527/2022/amt-15-5527-2022.pdf |
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