Uncertainty of atmospheric microwave absorption model: impact on ground-based radiometer simulations and retrievals
This paper presents a general approach to quantify absorption model uncertainty due to uncertainty in the underlying spectroscopic parameters. The approach is applied to a widely used microwave absorption model (Rosenkranz, 2017) and radiative transfer calculations in the 20–60 GHz range, which are...
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ftdoajarticles:oai:doaj.org/article:7035191438114782ba012904578e8d4f 2023-05-15T18:28:18+02:00 Uncertainty of atmospheric microwave absorption model: impact on ground-based radiometer simulations and retrievals D. Cimini P. W. Rosenkranz M. Y. Tretyakov M. A. Koshelev F. Romano 2018-10-01T00:00:00Z https://doi.org/10.5194/acp-18-15231-2018 https://doaj.org/article/7035191438114782ba012904578e8d4f EN eng Copernicus Publications https://www.atmos-chem-phys.net/18/15231/2018/acp-18-15231-2018.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 doi:10.5194/acp-18-15231-2018 1680-7316 1680-7324 https://doaj.org/article/7035191438114782ba012904578e8d4f Atmospheric Chemistry and Physics, Vol 18, Pp 15231-15259 (2018) Physics QC1-999 Chemistry QD1-999 article 2018 ftdoajarticles https://doi.org/10.5194/acp-18-15231-2018 2022-12-31T01:09:02Z This paper presents a general approach to quantify absorption model uncertainty due to uncertainty in the underlying spectroscopic parameters. The approach is applied to a widely used microwave absorption model (Rosenkranz, 2017) and radiative transfer calculations in the 20–60 GHz range, which are commonly exploited for atmospheric sounding by microwave radiometer (MWR). The approach, however, is not limited to any frequency range, observing geometry, or particular instrument. In the considered frequency range, relevant uncertainties come from water vapor and oxygen spectroscopic parameters. The uncertainty of the following parameters is found to dominate: (for water vapor) self- and foreign-continuum absorption coefficients, line broadening by dry air, line intensity, the temperature-dependence exponent for foreign-continuum absorption, and the line shift-to-broadening ratio; (for oxygen) line intensity, line broadening by dry air, line mixing, the temperature-dependence exponent for broadening, zero-frequency line broadening in air, and the temperature-dependence coefficient for line mixing. The full uncertainty covariance matrix is then computed for the set of spectroscopic parameters with significant impact. The impact of the spectroscopic parameter uncertainty covariance matrix on simulated downwelling microwave brightness temperatures ( T B ) in the 20–60 GHz range is calculated for six atmospheric climatology conditions. The uncertainty contribution to simulated T B ranges from 0.30 K (subarctic winter) to 0.92 K (tropical) at 22.2 GHz and from 2.73 K (tropical) to 3.31 K (subarctic winter) at 52.28 GHz. The uncertainty contribution is nearly zero at 55–60 GHz frequencies. Finally, the impact of spectroscopic parameter uncertainty on ground-based MWR retrievals of temperature and humidity profiles is discussed. Article in Journal/Newspaper Subarctic Directory of Open Access Journals: DOAJ Articles Atmospheric Chemistry and Physics 18 20 15231 15259 |
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English |
topic |
Physics QC1-999 Chemistry QD1-999 |
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Physics QC1-999 Chemistry QD1-999 D. Cimini P. W. Rosenkranz M. Y. Tretyakov M. A. Koshelev F. Romano Uncertainty of atmospheric microwave absorption model: impact on ground-based radiometer simulations and retrievals |
topic_facet |
Physics QC1-999 Chemistry QD1-999 |
description |
This paper presents a general approach to quantify absorption model uncertainty due to uncertainty in the underlying spectroscopic parameters. The approach is applied to a widely used microwave absorption model (Rosenkranz, 2017) and radiative transfer calculations in the 20–60 GHz range, which are commonly exploited for atmospheric sounding by microwave radiometer (MWR). The approach, however, is not limited to any frequency range, observing geometry, or particular instrument. In the considered frequency range, relevant uncertainties come from water vapor and oxygen spectroscopic parameters. The uncertainty of the following parameters is found to dominate: (for water vapor) self- and foreign-continuum absorption coefficients, line broadening by dry air, line intensity, the temperature-dependence exponent for foreign-continuum absorption, and the line shift-to-broadening ratio; (for oxygen) line intensity, line broadening by dry air, line mixing, the temperature-dependence exponent for broadening, zero-frequency line broadening in air, and the temperature-dependence coefficient for line mixing. The full uncertainty covariance matrix is then computed for the set of spectroscopic parameters with significant impact. The impact of the spectroscopic parameter uncertainty covariance matrix on simulated downwelling microwave brightness temperatures ( T B ) in the 20–60 GHz range is calculated for six atmospheric climatology conditions. The uncertainty contribution to simulated T B ranges from 0.30 K (subarctic winter) to 0.92 K (tropical) at 22.2 GHz and from 2.73 K (tropical) to 3.31 K (subarctic winter) at 52.28 GHz. The uncertainty contribution is nearly zero at 55–60 GHz frequencies. Finally, the impact of spectroscopic parameter uncertainty on ground-based MWR retrievals of temperature and humidity profiles is discussed. |
format |
Article in Journal/Newspaper |
author |
D. Cimini P. W. Rosenkranz M. Y. Tretyakov M. A. Koshelev F. Romano |
author_facet |
D. Cimini P. W. Rosenkranz M. Y. Tretyakov M. A. Koshelev F. Romano |
author_sort |
D. Cimini |
title |
Uncertainty of atmospheric microwave absorption model: impact on ground-based radiometer simulations and retrievals |
title_short |
Uncertainty of atmospheric microwave absorption model: impact on ground-based radiometer simulations and retrievals |
title_full |
Uncertainty of atmospheric microwave absorption model: impact on ground-based radiometer simulations and retrievals |
title_fullStr |
Uncertainty of atmospheric microwave absorption model: impact on ground-based radiometer simulations and retrievals |
title_full_unstemmed |
Uncertainty of atmospheric microwave absorption model: impact on ground-based radiometer simulations and retrievals |
title_sort |
uncertainty of atmospheric microwave absorption model: impact on ground-based radiometer simulations and retrievals |
publisher |
Copernicus Publications |
publishDate |
2018 |
url |
https://doi.org/10.5194/acp-18-15231-2018 https://doaj.org/article/7035191438114782ba012904578e8d4f |
genre |
Subarctic |
genre_facet |
Subarctic |
op_source |
Atmospheric Chemistry and Physics, Vol 18, Pp 15231-15259 (2018) |
op_relation |
https://www.atmos-chem-phys.net/18/15231/2018/acp-18-15231-2018.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 doi:10.5194/acp-18-15231-2018 1680-7316 1680-7324 https://doaj.org/article/7035191438114782ba012904578e8d4f |
op_doi |
https://doi.org/10.5194/acp-18-15231-2018 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
18 |
container_issue |
20 |
container_start_page |
15231 |
op_container_end_page |
15259 |
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1766210706002149376 |