Can liquid cloud microphysical processes be used for vertically pointing cloud radar calibration?
Cloud radars are unique instruments for observing cloud processes, but uncertainties in radar calibration have frequently limited data quality. Thus far, no single robust method exists for assessing the calibration of past cloud radar data sets. Here, we investigate whether observations of microphys...
Published in: | Atmospheric Measurement Techniques |
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Online Access: | https://doi.org/10.5194/amt-12-3151-2019 https://noa.gwlb.de/receive/cop_mods_00001687 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00001646/amt-12-3151-2019.pdf https://amt.copernicus.org/articles/12/3151/2019/amt-12-3151-2019.pdf |
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ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00001687 2023-05-15T17:40:15+02:00 Can liquid cloud microphysical processes be used for vertically pointing cloud radar calibration? Maahn, Maximilian Hoffmann, Fabian Shupe, Matthew D. de Boer, Gijs Matrosov, Sergey Y. Luke, Edward P. 2019-06 electronic https://doi.org/10.5194/amt-12-3151-2019 https://noa.gwlb.de/receive/cop_mods_00001687 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00001646/amt-12-3151-2019.pdf https://amt.copernicus.org/articles/12/3151/2019/amt-12-3151-2019.pdf eng eng Copernicus Publications Atmospheric Measurement Techniques -- http://www.bibliothek.uni-regensburg.de/ezeit/?2505596 -- http://www.atmospheric-measurement-techniques.net/ -- 1867-8548 https://doi.org/10.5194/amt-12-3151-2019 https://noa.gwlb.de/receive/cop_mods_00001687 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00001646/amt-12-3151-2019.pdf https://amt.copernicus.org/articles/12/3151/2019/amt-12-3151-2019.pdf https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess CC-BY article Verlagsveröffentlichung article Text doc-type:article 2019 ftnonlinearchiv https://doi.org/10.5194/amt-12-3151-2019 2022-02-08T23:01:41Z Cloud radars are unique instruments for observing cloud processes, but uncertainties in radar calibration have frequently limited data quality. Thus far, no single robust method exists for assessing the calibration of past cloud radar data sets. Here, we investigate whether observations of microphysical processes in liquid clouds such as the transition of cloud droplets to drizzle drops can be used to calibrate cloud radars. Specifically, we study the relationships between the radar reflectivity factor and three variables not affected by absolute radar calibration: the skewness of the radar Doppler spectrum (γ), the radar mean Doppler velocity (W), and the liquid water path (LWP). For each relation, we evaluate the potential for radar calibration. For γ and W, we use box model simulations to determine typical radar reflectivity values for reference points. We apply the new methods to observations at the Atmospheric Radiation Measurement (ARM) sites North Slope of Alaska (NSA) and Oliktok Point (OLI) in 2016 using two 35 GHz Ka-band ARM Zenith Radars (KAZR). For periods with a sufficient number of liquid cloud observations, we find that liquid cloud processes are robust enough for cloud radar calibration, with the LWP-based method performing best. We estimate that, in 2016, the radar reflectivity at NSA was about 1±1 dB too low but stable. For OLI, we identify serious problems with maintaining an accurate calibration including a sudden decrease of 5 to 7 dB in June 2016. Article in Journal/Newspaper north slope Alaska Niedersächsisches Online-Archiv NOA Atmospheric Measurement Techniques 12 6 3151 3171 |
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Open Polar |
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Niedersächsisches Online-Archiv NOA |
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ftnonlinearchiv |
language |
English |
topic |
article Verlagsveröffentlichung |
spellingShingle |
article Verlagsveröffentlichung Maahn, Maximilian Hoffmann, Fabian Shupe, Matthew D. de Boer, Gijs Matrosov, Sergey Y. Luke, Edward P. Can liquid cloud microphysical processes be used for vertically pointing cloud radar calibration? |
topic_facet |
article Verlagsveröffentlichung |
description |
Cloud radars are unique instruments for observing cloud processes, but uncertainties in radar calibration have frequently limited data quality. Thus far, no single robust method exists for assessing the calibration of past cloud radar data sets. Here, we investigate whether observations of microphysical processes in liquid clouds such as the transition of cloud droplets to drizzle drops can be used to calibrate cloud radars. Specifically, we study the relationships between the radar reflectivity factor and three variables not affected by absolute radar calibration: the skewness of the radar Doppler spectrum (γ), the radar mean Doppler velocity (W), and the liquid water path (LWP). For each relation, we evaluate the potential for radar calibration. For γ and W, we use box model simulations to determine typical radar reflectivity values for reference points. We apply the new methods to observations at the Atmospheric Radiation Measurement (ARM) sites North Slope of Alaska (NSA) and Oliktok Point (OLI) in 2016 using two 35 GHz Ka-band ARM Zenith Radars (KAZR). For periods with a sufficient number of liquid cloud observations, we find that liquid cloud processes are robust enough for cloud radar calibration, with the LWP-based method performing best. We estimate that, in 2016, the radar reflectivity at NSA was about 1±1 dB too low but stable. For OLI, we identify serious problems with maintaining an accurate calibration including a sudden decrease of 5 to 7 dB in June 2016. |
format |
Article in Journal/Newspaper |
author |
Maahn, Maximilian Hoffmann, Fabian Shupe, Matthew D. de Boer, Gijs Matrosov, Sergey Y. Luke, Edward P. |
author_facet |
Maahn, Maximilian Hoffmann, Fabian Shupe, Matthew D. de Boer, Gijs Matrosov, Sergey Y. Luke, Edward P. |
author_sort |
Maahn, Maximilian |
title |
Can liquid cloud microphysical processes be used for vertically pointing cloud radar calibration? |
title_short |
Can liquid cloud microphysical processes be used for vertically pointing cloud radar calibration? |
title_full |
Can liquid cloud microphysical processes be used for vertically pointing cloud radar calibration? |
title_fullStr |
Can liquid cloud microphysical processes be used for vertically pointing cloud radar calibration? |
title_full_unstemmed |
Can liquid cloud microphysical processes be used for vertically pointing cloud radar calibration? |
title_sort |
can liquid cloud microphysical processes be used for vertically pointing cloud radar calibration? |
publisher |
Copernicus Publications |
publishDate |
2019 |
url |
https://doi.org/10.5194/amt-12-3151-2019 https://noa.gwlb.de/receive/cop_mods_00001687 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00001646/amt-12-3151-2019.pdf https://amt.copernicus.org/articles/12/3151/2019/amt-12-3151-2019.pdf |
genre |
north slope Alaska |
genre_facet |
north slope Alaska |
op_relation |
Atmospheric Measurement Techniques -- http://www.bibliothek.uni-regensburg.de/ezeit/?2505596 -- http://www.atmospheric-measurement-techniques.net/ -- 1867-8548 https://doi.org/10.5194/amt-12-3151-2019 https://noa.gwlb.de/receive/cop_mods_00001687 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00001646/amt-12-3151-2019.pdf https://amt.copernicus.org/articles/12/3151/2019/amt-12-3151-2019.pdf |
op_rights |
https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/amt-12-3151-2019 |
container_title |
Atmospheric Measurement Techniques |
container_volume |
12 |
container_issue |
6 |
container_start_page |
3151 |
op_container_end_page |
3171 |
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1766141135485403136 |