Development and application of a backscatter lidar forward operator for quantitative validation of aerosol dispersion models and future data assimilation
A new backscatter lidar forward operator was developed which is based on the distinct calculation of the aerosols' backscatter and extinction properties. The forward operator was adapted to the COSMO-ART ash dispersion simulation of the Eyjafjallajökull eruption in 2010. While the particle numb...
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ftdoajarticles:oai:doaj.org/article:f7ef740ed2f046c889891b20965799c6 2023-05-15T16:09:39+02:00 Development and application of a backscatter lidar forward operator for quantitative validation of aerosol dispersion models and future data assimilation A. Geisinger A. Behrendt V. Wulfmeyer J. Strohbach J. Förstner R. Potthast 2017-12-01T00:00:00Z https://doi.org/10.5194/amt-10-4705-2017 https://doaj.org/article/f7ef740ed2f046c889891b20965799c6 EN eng Copernicus Publications https://www.atmos-meas-tech.net/10/4705/2017/amt-10-4705-2017.pdf https://doaj.org/toc/1867-1381 https://doaj.org/toc/1867-8548 doi:10.5194/amt-10-4705-2017 1867-1381 1867-8548 https://doaj.org/article/f7ef740ed2f046c889891b20965799c6 Atmospheric Measurement Techniques, Vol 10, Pp 4705-4726 (2017) Environmental engineering TA170-171 Earthwork. Foundations TA715-787 article 2017 ftdoajarticles https://doi.org/10.5194/amt-10-4705-2017 2022-12-31T01:12:59Z A new backscatter lidar forward operator was developed which is based on the distinct calculation of the aerosols' backscatter and extinction properties. The forward operator was adapted to the COSMO-ART ash dispersion simulation of the Eyjafjallajökull eruption in 2010. While the particle number concentration was provided as a model output variable, the scattering properties of each individual particle type were determined by dedicated scattering calculations. Sensitivity studies were performed to estimate the uncertainties related to the assumed particle properties. Scattering calculations for several types of non-spherical particles required the usage of T-matrix routines. Due to the distinct calculation of the backscatter and extinction properties of the models' volcanic ash size classes, the sensitivity studies could be made for each size class individually, which is not the case for forward models based on a fixed lidar ratio. Finally, the forward-modeled lidar profiles have been compared to automated ceilometer lidar (ACL) measurements both qualitatively and quantitatively while the attenuated backscatter coefficient was chosen as a suitable physical quantity. As the ACL measurements were not calibrated automatically, their calibration had to be performed using satellite lidar and ground-based Raman lidar measurements. A slight overestimation of the model-predicted volcanic ash number density was observed. Major requirements for future data assimilation of data from ACL have been identified, namely, the availability of calibrated lidar measurement data, a scattering database for atmospheric aerosols, a better representation and coverage of aerosols by the ash dispersion model, and more investigation in backscatter lidar forward operators which calculate the backscatter coefficient directly for each individual aerosol type. The introduced forward operator offers the flexibility to be adapted to a multitude of model systems and measurement setups. Article in Journal/Newspaper Eyjafjallajökull Directory of Open Access Journals: DOAJ Articles Atmospheric Measurement Techniques 10 12 4705 4726 |
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Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
language |
English |
topic |
Environmental engineering TA170-171 Earthwork. Foundations TA715-787 |
spellingShingle |
Environmental engineering TA170-171 Earthwork. Foundations TA715-787 A. Geisinger A. Behrendt V. Wulfmeyer J. Strohbach J. Förstner R. Potthast Development and application of a backscatter lidar forward operator for quantitative validation of aerosol dispersion models and future data assimilation |
topic_facet |
Environmental engineering TA170-171 Earthwork. Foundations TA715-787 |
description |
A new backscatter lidar forward operator was developed which is based on the distinct calculation of the aerosols' backscatter and extinction properties. The forward operator was adapted to the COSMO-ART ash dispersion simulation of the Eyjafjallajökull eruption in 2010. While the particle number concentration was provided as a model output variable, the scattering properties of each individual particle type were determined by dedicated scattering calculations. Sensitivity studies were performed to estimate the uncertainties related to the assumed particle properties. Scattering calculations for several types of non-spherical particles required the usage of T-matrix routines. Due to the distinct calculation of the backscatter and extinction properties of the models' volcanic ash size classes, the sensitivity studies could be made for each size class individually, which is not the case for forward models based on a fixed lidar ratio. Finally, the forward-modeled lidar profiles have been compared to automated ceilometer lidar (ACL) measurements both qualitatively and quantitatively while the attenuated backscatter coefficient was chosen as a suitable physical quantity. As the ACL measurements were not calibrated automatically, their calibration had to be performed using satellite lidar and ground-based Raman lidar measurements. A slight overestimation of the model-predicted volcanic ash number density was observed. Major requirements for future data assimilation of data from ACL have been identified, namely, the availability of calibrated lidar measurement data, a scattering database for atmospheric aerosols, a better representation and coverage of aerosols by the ash dispersion model, and more investigation in backscatter lidar forward operators which calculate the backscatter coefficient directly for each individual aerosol type. The introduced forward operator offers the flexibility to be adapted to a multitude of model systems and measurement setups. |
format |
Article in Journal/Newspaper |
author |
A. Geisinger A. Behrendt V. Wulfmeyer J. Strohbach J. Förstner R. Potthast |
author_facet |
A. Geisinger A. Behrendt V. Wulfmeyer J. Strohbach J. Förstner R. Potthast |
author_sort |
A. Geisinger |
title |
Development and application of a backscatter lidar forward operator for quantitative validation of aerosol dispersion models and future data assimilation |
title_short |
Development and application of a backscatter lidar forward operator for quantitative validation of aerosol dispersion models and future data assimilation |
title_full |
Development and application of a backscatter lidar forward operator for quantitative validation of aerosol dispersion models and future data assimilation |
title_fullStr |
Development and application of a backscatter lidar forward operator for quantitative validation of aerosol dispersion models and future data assimilation |
title_full_unstemmed |
Development and application of a backscatter lidar forward operator for quantitative validation of aerosol dispersion models and future data assimilation |
title_sort |
development and application of a backscatter lidar forward operator for quantitative validation of aerosol dispersion models and future data assimilation |
publisher |
Copernicus Publications |
publishDate |
2017 |
url |
https://doi.org/10.5194/amt-10-4705-2017 https://doaj.org/article/f7ef740ed2f046c889891b20965799c6 |
genre |
Eyjafjallajökull |
genre_facet |
Eyjafjallajökull |
op_source |
Atmospheric Measurement Techniques, Vol 10, Pp 4705-4726 (2017) |
op_relation |
https://www.atmos-meas-tech.net/10/4705/2017/amt-10-4705-2017.pdf https://doaj.org/toc/1867-1381 https://doaj.org/toc/1867-8548 doi:10.5194/amt-10-4705-2017 1867-1381 1867-8548 https://doaj.org/article/f7ef740ed2f046c889891b20965799c6 |
op_doi |
https://doi.org/10.5194/amt-10-4705-2017 |
container_title |
Atmospheric Measurement Techniques |
container_volume |
10 |
container_issue |
12 |
container_start_page |
4705 |
op_container_end_page |
4726 |
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1766405501579427840 |