Mind the gap – Part 1: Accurately locating warm marine boundary layer clouds and precipitation using spaceborne radars
Ground-based radar observations show that, over the eastern North Atlantic, 50 % of warm marine boundary layer (WMBL) hydrometeors occur below 1.2 km and have reflectivities of < −17 dBZ, thus making their detection from space susceptible to the extent of surface clutter and radar sensitivity. Su...
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ftdoajarticles:oai:doaj.org/article:b2a548959b4e48cab0fc6c885845b269 2023-05-15T17:35:15+02:00 Mind the gap – Part 1: Accurately locating warm marine boundary layer clouds and precipitation using spaceborne radars K. Lamer P. Kollias A. Battaglia S. Preval 2020-05-01T00:00:00Z https://doi.org/10.5194/amt-13-2363-2020 https://doaj.org/article/b2a548959b4e48cab0fc6c885845b269 EN eng Copernicus Publications https://www.atmos-meas-tech.net/13/2363/2020/amt-13-2363-2020.pdf https://doaj.org/toc/1867-1381 https://doaj.org/toc/1867-8548 doi:10.5194/amt-13-2363-2020 1867-1381 1867-8548 https://doaj.org/article/b2a548959b4e48cab0fc6c885845b269 Atmospheric Measurement Techniques, Vol 13, Pp 2363-2379 (2020) Environmental engineering TA170-171 Earthwork. Foundations TA715-787 article 2020 ftdoajarticles https://doi.org/10.5194/amt-13-2363-2020 2023-01-08T01:34:18Z Ground-based radar observations show that, over the eastern North Atlantic, 50 % of warm marine boundary layer (WMBL) hydrometeors occur below 1.2 km and have reflectivities of < −17 dBZ, thus making their detection from space susceptible to the extent of surface clutter and radar sensitivity. Surface clutter limits the ability of the CloudSat cloud profiling radar (CPR) to observe the true cloud base in ∼52 % of the cloudy columns it detects and true virga base in ∼80 %, meaning the CloudSat CPR often provides an incomplete view of even the clouds it does detect. Using forward simulations, we determine that a 250 m resolution radar would most accurately capture the boundaries of WMBL clouds and precipitation; that being said, because of sensitivity limitations, such a radar would suffer from cloud cover biases similar to those of the CloudSat CPR. Observations and forward simulations indicate that the CloudSat CPR fails to detect 29 %–43 % of the cloudy columns detected by ground-based sensors. Out of all configurations tested, the 7 dB more sensitive EarthCARE CPR performs best (only missing 9.0 % of cloudy columns) indicating that improving radar sensitivity is more important than decreasing the vertical extent of surface clutter for measuring cloud cover. However, because 50 % of WMBL systems are thinner than 400 m, they tend to be artificially stretched by long sensitive radar pulses, hence the EarthCARE CPR overestimation of cloud top height and hydrometeor fraction. Thus, it is recommended that the next generation of space-borne radars targeting WMBL science should operate interlaced pulse modes including both a highly sensitive long-pulse mode and a less sensitive but clutter-limiting short-pulse mode. Article in Journal/Newspaper North Atlantic Directory of Open Access Journals: DOAJ Articles Atmospheric Measurement Techniques 13 5 2363 2379 |
institution |
Open Polar |
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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 |
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Environmental engineering TA170-171 Earthwork. Foundations TA715-787 K. Lamer P. Kollias A. Battaglia S. Preval Mind the gap – Part 1: Accurately locating warm marine boundary layer clouds and precipitation using spaceborne radars |
topic_facet |
Environmental engineering TA170-171 Earthwork. Foundations TA715-787 |
description |
Ground-based radar observations show that, over the eastern North Atlantic, 50 % of warm marine boundary layer (WMBL) hydrometeors occur below 1.2 km and have reflectivities of < −17 dBZ, thus making their detection from space susceptible to the extent of surface clutter and radar sensitivity. Surface clutter limits the ability of the CloudSat cloud profiling radar (CPR) to observe the true cloud base in ∼52 % of the cloudy columns it detects and true virga base in ∼80 %, meaning the CloudSat CPR often provides an incomplete view of even the clouds it does detect. Using forward simulations, we determine that a 250 m resolution radar would most accurately capture the boundaries of WMBL clouds and precipitation; that being said, because of sensitivity limitations, such a radar would suffer from cloud cover biases similar to those of the CloudSat CPR. Observations and forward simulations indicate that the CloudSat CPR fails to detect 29 %–43 % of the cloudy columns detected by ground-based sensors. Out of all configurations tested, the 7 dB more sensitive EarthCARE CPR performs best (only missing 9.0 % of cloudy columns) indicating that improving radar sensitivity is more important than decreasing the vertical extent of surface clutter for measuring cloud cover. However, because 50 % of WMBL systems are thinner than 400 m, they tend to be artificially stretched by long sensitive radar pulses, hence the EarthCARE CPR overestimation of cloud top height and hydrometeor fraction. Thus, it is recommended that the next generation of space-borne radars targeting WMBL science should operate interlaced pulse modes including both a highly sensitive long-pulse mode and a less sensitive but clutter-limiting short-pulse mode. |
format |
Article in Journal/Newspaper |
author |
K. Lamer P. Kollias A. Battaglia S. Preval |
author_facet |
K. Lamer P. Kollias A. Battaglia S. Preval |
author_sort |
K. Lamer |
title |
Mind the gap – Part 1: Accurately locating warm marine boundary layer clouds and precipitation using spaceborne radars |
title_short |
Mind the gap – Part 1: Accurately locating warm marine boundary layer clouds and precipitation using spaceborne radars |
title_full |
Mind the gap – Part 1: Accurately locating warm marine boundary layer clouds and precipitation using spaceborne radars |
title_fullStr |
Mind the gap – Part 1: Accurately locating warm marine boundary layer clouds and precipitation using spaceborne radars |
title_full_unstemmed |
Mind the gap – Part 1: Accurately locating warm marine boundary layer clouds and precipitation using spaceborne radars |
title_sort |
mind the gap – part 1: accurately locating warm marine boundary layer clouds and precipitation using spaceborne radars |
publisher |
Copernicus Publications |
publishDate |
2020 |
url |
https://doi.org/10.5194/amt-13-2363-2020 https://doaj.org/article/b2a548959b4e48cab0fc6c885845b269 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Atmospheric Measurement Techniques, Vol 13, Pp 2363-2379 (2020) |
op_relation |
https://www.atmos-meas-tech.net/13/2363/2020/amt-13-2363-2020.pdf https://doaj.org/toc/1867-1381 https://doaj.org/toc/1867-8548 doi:10.5194/amt-13-2363-2020 1867-1381 1867-8548 https://doaj.org/article/b2a548959b4e48cab0fc6c885845b269 |
op_doi |
https://doi.org/10.5194/amt-13-2363-2020 |
container_title |
Atmospheric Measurement Techniques |
container_volume |
13 |
container_issue |
5 |
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2363 |
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2379 |
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