Microwave Radar/radiometer for Arctic Clouds (MiRAC): first insights from the ACLOUD campaign
The Microwave Radar/radiometer for Arctic Clouds (MiRAC) is a novel instrument package developed to study the vertical structure and characteristics of clouds and precipitation on board the Polar 5 research aircraft. MiRAC combines a frequency-modulated continuous wave (FMCW) radar at 94 GHz includi...
Published in: | Atmospheric Measurement Techniques |
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Format: | Article in Journal/Newspaper |
Language: | English |
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Copernicus Publications
2019
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Online Access: | https://doi.org/10.5194/amt-12-5019-2019 https://noa.gwlb.de/receive/cop_mods_00040394 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00040018/amt-12-5019-2019.pdf https://amt.copernicus.org/articles/12/5019/2019/amt-12-5019-2019.pdf |
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ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00040394 2023-05-15T14:55:23+02:00 Microwave Radar/radiometer for Arctic Clouds (MiRAC): first insights from the ACLOUD campaign Mech, Mario Kliesch, Leif-Leonard Anhäuser, Andreas Rose, Thomas Kollias, Pavlos Crewell, Susanne 2019-09 electronic https://doi.org/10.5194/amt-12-5019-2019 https://noa.gwlb.de/receive/cop_mods_00040394 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00040018/amt-12-5019-2019.pdf https://amt.copernicus.org/articles/12/5019/2019/amt-12-5019-2019.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-12-5019-2019 https://noa.gwlb.de/receive/cop_mods_00040394 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00040018/amt-12-5019-2019.pdf https://amt.copernicus.org/articles/12/5019/2019/amt-12-5019-2019.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-12-5019-2019 2022-02-08T22:42:10Z The Microwave Radar/radiometer for Arctic Clouds (MiRAC) is a novel instrument package developed to study the vertical structure and characteristics of clouds and precipitation on board the Polar 5 research aircraft. MiRAC combines a frequency-modulated continuous wave (FMCW) radar at 94 GHz including a 89 GHz passive channel (MiRAC-A) and an eight-channel radiometer with frequencies between 175 and 340 GHz (MiRAC-P). The radar can be flexibly operated using different chirp sequences to provide measurements of the equivalent radar reflectivity with different vertical resolution down to 5 m. MiRAC is mounted for down-looking geometry on Polar 5 to enable the synergy with lidar and radiation measurements. To mitigate the influence of the strong surface backscatter the radar is mounted with an inclination of about 25∘ backward in a belly pod under the Polar 5 aircraft. Procedures for filtering ground return and range side lobes have been developed. MiRAC-P frequencies are especially adopted for low-humidity conditions typical for the Arctic to provide information on water vapor and hydrometeor content. MiRAC has been operated on 19 research flights during the ACLOUD campaign in the vicinity of Svalbard in May–June 2017 providing in total 48 h of measurements from flight altitudes >2300 m. The radar measurements have been carefully quality controlled and corrected for surface clutter, mounting of the instrument, and aircraft orientation to provide measurements on a unified, geo-referenced vertical grid allowing the combination with the other nadir-pointing instruments. An intercomparison with CloudSat shows good agreement in terms of cloud top height of 1.5 km and radar reflectivity up to −5 dBz and demonstrates that MiRAC with its more than 10 times higher vertical resolution down to about 150 m above the surface is able to show to some extent what is missed by CloudSat when observing low-level clouds. This is especially important for the Arctic as about 40 % of the clouds during ACLOUD showed cloud tops below 1000 m, i.e., the blind zone of CloudSat. In addition, with MiRAC-A 89 GHz it is possible to get an estimate of the sea ice concentration with a much higher resolution than the daily AMSR2 sea ice product on a 6.25 km grid. Article in Journal/Newspaper Arctic Sea ice Svalbard Niedersächsisches Online-Archiv NOA Arctic Svalbard Atmospheric Measurement Techniques 12 9 5019 5037 |
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Open Polar |
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Niedersächsisches Online-Archiv NOA |
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ftnonlinearchiv |
language |
English |
topic |
article Verlagsveröffentlichung |
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article Verlagsveröffentlichung Mech, Mario Kliesch, Leif-Leonard Anhäuser, Andreas Rose, Thomas Kollias, Pavlos Crewell, Susanne Microwave Radar/radiometer for Arctic Clouds (MiRAC): first insights from the ACLOUD campaign |
topic_facet |
article Verlagsveröffentlichung |
description |
The Microwave Radar/radiometer for Arctic Clouds (MiRAC) is a novel instrument package developed to study the vertical structure and characteristics of clouds and precipitation on board the Polar 5 research aircraft. MiRAC combines a frequency-modulated continuous wave (FMCW) radar at 94 GHz including a 89 GHz passive channel (MiRAC-A) and an eight-channel radiometer with frequencies between 175 and 340 GHz (MiRAC-P). The radar can be flexibly operated using different chirp sequences to provide measurements of the equivalent radar reflectivity with different vertical resolution down to 5 m. MiRAC is mounted for down-looking geometry on Polar 5 to enable the synergy with lidar and radiation measurements. To mitigate the influence of the strong surface backscatter the radar is mounted with an inclination of about 25∘ backward in a belly pod under the Polar 5 aircraft. Procedures for filtering ground return and range side lobes have been developed. MiRAC-P frequencies are especially adopted for low-humidity conditions typical for the Arctic to provide information on water vapor and hydrometeor content. MiRAC has been operated on 19 research flights during the ACLOUD campaign in the vicinity of Svalbard in May–June 2017 providing in total 48 h of measurements from flight altitudes >2300 m. The radar measurements have been carefully quality controlled and corrected for surface clutter, mounting of the instrument, and aircraft orientation to provide measurements on a unified, geo-referenced vertical grid allowing the combination with the other nadir-pointing instruments. An intercomparison with CloudSat shows good agreement in terms of cloud top height of 1.5 km and radar reflectivity up to −5 dBz and demonstrates that MiRAC with its more than 10 times higher vertical resolution down to about 150 m above the surface is able to show to some extent what is missed by CloudSat when observing low-level clouds. This is especially important for the Arctic as about 40 % of the clouds during ACLOUD showed cloud tops below 1000 m, i.e., the blind zone of CloudSat. In addition, with MiRAC-A 89 GHz it is possible to get an estimate of the sea ice concentration with a much higher resolution than the daily AMSR2 sea ice product on a 6.25 km grid. |
format |
Article in Journal/Newspaper |
author |
Mech, Mario Kliesch, Leif-Leonard Anhäuser, Andreas Rose, Thomas Kollias, Pavlos Crewell, Susanne |
author_facet |
Mech, Mario Kliesch, Leif-Leonard Anhäuser, Andreas Rose, Thomas Kollias, Pavlos Crewell, Susanne |
author_sort |
Mech, Mario |
title |
Microwave Radar/radiometer for Arctic Clouds (MiRAC): first insights from the ACLOUD campaign |
title_short |
Microwave Radar/radiometer for Arctic Clouds (MiRAC): first insights from the ACLOUD campaign |
title_full |
Microwave Radar/radiometer for Arctic Clouds (MiRAC): first insights from the ACLOUD campaign |
title_fullStr |
Microwave Radar/radiometer for Arctic Clouds (MiRAC): first insights from the ACLOUD campaign |
title_full_unstemmed |
Microwave Radar/radiometer for Arctic Clouds (MiRAC): first insights from the ACLOUD campaign |
title_sort |
microwave radar/radiometer for arctic clouds (mirac): first insights from the acloud campaign |
publisher |
Copernicus Publications |
publishDate |
2019 |
url |
https://doi.org/10.5194/amt-12-5019-2019 https://noa.gwlb.de/receive/cop_mods_00040394 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00040018/amt-12-5019-2019.pdf https://amt.copernicus.org/articles/12/5019/2019/amt-12-5019-2019.pdf |
geographic |
Arctic Svalbard |
geographic_facet |
Arctic Svalbard |
genre |
Arctic Sea ice Svalbard |
genre_facet |
Arctic Sea ice Svalbard |
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-12-5019-2019 https://noa.gwlb.de/receive/cop_mods_00040394 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00040018/amt-12-5019-2019.pdf https://amt.copernicus.org/articles/12/5019/2019/amt-12-5019-2019.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-12-5019-2019 |
container_title |
Atmospheric Measurement Techniques |
container_volume |
12 |
container_issue |
9 |
container_start_page |
5019 |
op_container_end_page |
5037 |
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1766327182474346496 |