Improvement of airborne retrievals of cloud droplet number concentration of trade wind cumulus using a synergetic approach
In situ measurements of cloud droplet number concentration N are limited by the sampled cloud volume. Satellite retrievals of N suffer from inherent uncertainties, spatial averaging, and retrieval problems arising from the commonly assumed strictly adiabatic vertical profiles of cloud properties. To...
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ftcopernicus:oai:publications.copernicus.org:amt70804 2023-05-15T18:50:43+02:00 Improvement of airborne retrievals of cloud droplet number concentration of trade wind cumulus using a synergetic approach Wolf, Kevin Ehrlich, André Jacob, Marek Crewell, Susanne Wirth, Martin Wendisch, Manfred 2019-03-26 application/pdf https://doi.org/10.5194/amt-12-1635-2019 https://amt.copernicus.org/articles/12/1635/2019/ eng eng doi:10.5194/amt-12-1635-2019 https://amt.copernicus.org/articles/12/1635/2019/ eISSN: 1867-8548 Text 2019 ftcopernicus https://doi.org/10.5194/amt-12-1635-2019 2020-07-20T16:22:54Z In situ measurements of cloud droplet number concentration N are limited by the sampled cloud volume. Satellite retrievals of N suffer from inherent uncertainties, spatial averaging, and retrieval problems arising from the commonly assumed strictly adiabatic vertical profiles of cloud properties. To improve retrievals of N it is suggested in this paper to use a synergetic combination of passive and active airborne remote sensing measurement, to reduce the uncertainty of N retrievals, and to bridge the gap between in situ cloud sampling and global averaging. For this purpose, spectral solar radiation measurements above shallow trade wind cumulus were combined with passive microwave and active radar and lidar observations carried out during the second Next Generation Remote Sensing for Validation Studies (NARVAL-II) campaign with the High Altitude and Long Range Research Aircraft (HALO) in August 2016. The common technique to retrieve N is refined by including combined measurements and retrievals of cloud optical thickness τ , liquid water path (LWP), cloud droplet effective radius r eff , and cloud base and top altitude. Three approaches are tested and applied to synthetic measurements and two cloud scenarios observed during NARVAL-II. Using the new combined retrieval technique, errors in N due to the adiabatic assumption have been reduced significantly. Text narval narval Copernicus Publications: E-Journals Atmospheric Measurement Techniques 12 3 1635 1658 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
In situ measurements of cloud droplet number concentration N are limited by the sampled cloud volume. Satellite retrievals of N suffer from inherent uncertainties, spatial averaging, and retrieval problems arising from the commonly assumed strictly adiabatic vertical profiles of cloud properties. To improve retrievals of N it is suggested in this paper to use a synergetic combination of passive and active airborne remote sensing measurement, to reduce the uncertainty of N retrievals, and to bridge the gap between in situ cloud sampling and global averaging. For this purpose, spectral solar radiation measurements above shallow trade wind cumulus were combined with passive microwave and active radar and lidar observations carried out during the second Next Generation Remote Sensing for Validation Studies (NARVAL-II) campaign with the High Altitude and Long Range Research Aircraft (HALO) in August 2016. The common technique to retrieve N is refined by including combined measurements and retrievals of cloud optical thickness τ , liquid water path (LWP), cloud droplet effective radius r eff , and cloud base and top altitude. Three approaches are tested and applied to synthetic measurements and two cloud scenarios observed during NARVAL-II. Using the new combined retrieval technique, errors in N due to the adiabatic assumption have been reduced significantly. |
format |
Text |
author |
Wolf, Kevin Ehrlich, André Jacob, Marek Crewell, Susanne Wirth, Martin Wendisch, Manfred |
spellingShingle |
Wolf, Kevin Ehrlich, André Jacob, Marek Crewell, Susanne Wirth, Martin Wendisch, Manfred Improvement of airborne retrievals of cloud droplet number concentration of trade wind cumulus using a synergetic approach |
author_facet |
Wolf, Kevin Ehrlich, André Jacob, Marek Crewell, Susanne Wirth, Martin Wendisch, Manfred |
author_sort |
Wolf, Kevin |
title |
Improvement of airborne retrievals of cloud droplet number concentration of trade wind cumulus using a synergetic approach |
title_short |
Improvement of airborne retrievals of cloud droplet number concentration of trade wind cumulus using a synergetic approach |
title_full |
Improvement of airborne retrievals of cloud droplet number concentration of trade wind cumulus using a synergetic approach |
title_fullStr |
Improvement of airborne retrievals of cloud droplet number concentration of trade wind cumulus using a synergetic approach |
title_full_unstemmed |
Improvement of airborne retrievals of cloud droplet number concentration of trade wind cumulus using a synergetic approach |
title_sort |
improvement of airborne retrievals of cloud droplet number concentration of trade wind cumulus using a synergetic approach |
publishDate |
2019 |
url |
https://doi.org/10.5194/amt-12-1635-2019 https://amt.copernicus.org/articles/12/1635/2019/ |
genre |
narval narval |
genre_facet |
narval narval |
op_source |
eISSN: 1867-8548 |
op_relation |
doi:10.5194/amt-12-1635-2019 https://amt.copernicus.org/articles/12/1635/2019/ |
op_doi |
https://doi.org/10.5194/amt-12-1635-2019 |
container_title |
Atmospheric Measurement Techniques |
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12 |
container_issue |
3 |
container_start_page |
1635 |
op_container_end_page |
1658 |
_version_ |
1766244471394009088 |