Synergistic radar and radiometer retrievals of ice hydrometeors
<p>Remote sensing observations at sub-millimeter wavelengths provide higher sensitivity to small hydrometeors and low water content than observations at millimeter wavelengths, which are traditionally used to observe clouds and precipitation. They are employed increasingly in field campaigns t...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2020-08-01
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| Series: | Atmospheric Measurement Techniques |
| Online Access: | https://amt.copernicus.org/articles/13/4219/2020/amt-13-4219-2020.pdf |
| _version_ | 1828398055038124032 |
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| author | S. Pfreundschuh P. Eriksson S. A. Buehler M. Brath D. Duncan D. Duncan R. Larsson R. Ekelund |
| author_facet | S. Pfreundschuh P. Eriksson S. A. Buehler M. Brath D. Duncan D. Duncan R. Larsson R. Ekelund |
| author_sort | S. Pfreundschuh |
| collection | DOAJ |
| description | <p>Remote sensing observations at sub-millimeter wavelengths provide higher
sensitivity to small hydrometeors and low water content than observations at
millimeter wavelengths, which are traditionally used to observe clouds and
precipitation. They are employed increasingly in field campaigns to study cloud
microphysics and will be integrated into the global meteorological observing
system to measure the global distribution of ice in the atmosphere with the
launch of the Ice Cloud Imager (ICI) radiometer on board the second generation
of European operational meteorological satellites (Metop-SG). Observations at
these novel wavelengths provide valuable information not only on their own but
also in combination with complementary observations at other wavelengths. This
study investigates the potential of combining passive sub-millimeter radiometer
observations with a hypothetical W-band cloud radar for the retrieval of frozen
hydrometeors. An idealized cloud model is used to investigate the information
content of the combined observations and establish their capacity to constrain the
microphysical properties of ice hydrometeors. A synergistic retrieval algorithm
for airborne observations is proposed and applied to simulated observations from
a cloud-resolving model. Results from the synergistic retrieval are compared to
equivalent radar- and passive-only implementations in order to assess the
benefits of the synergistic sensor configuration. The impact of the assumed ice
particle shape on the retrieval results is assessed for all retrieval
implementations. We find that the combined observations better constrain the
microphysical properties of ice hydrometeors, which reduces uncertainties in
retrieved ice water content and particle number concentrations for suitable
choices of the ice particle model. Analysis of the retrieval information content
shows that, although the radar contributes the largest part of the information in the
combined retrieval, the radiometer observations provide complementary
information over a wide range of atmospheric states. Furthermore, the combined
observations yield slightly improved retrievals of liquid cloud water in
mixed-phase clouds, pointing towards another potential application of combined
radar–radiometer observations.</p> |
| first_indexed | 2024-12-10T08:55:37Z |
| format | Article |
| id | doaj.art-f50748aacfb24be3a78225763b6c0b7c |
| institution | Directory Open Access Journal |
| issn | 1867-1381 1867-8548 |
| language | English |
| last_indexed | 2024-12-10T08:55:37Z |
| publishDate | 2020-08-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Measurement Techniques |
| spelling | doaj.art-f50748aacfb24be3a78225763b6c0b7c2022-12-22T01:55:26ZengCopernicus PublicationsAtmospheric Measurement Techniques1867-13811867-85482020-08-01134219424510.5194/amt-13-4219-2020Synergistic radar and radiometer retrievals of ice hydrometeorsS. Pfreundschuh0P. Eriksson1S. A. Buehler2M. Brath3D. Duncan4D. Duncan5R. Larsson6R. Ekelund7Department of Space, Earth and Environment, Chalmers University of Technology, 41296 Gothenburg, SwedenDepartment of Space, Earth and Environment, Chalmers University of Technology, 41296 Gothenburg, SwedenMeteorologisches Institut, Fachbereich Geowissenschaften, Centrum für Erdsystem und Nachhaltigkeitsforschung (CEN), Universität Hamburg, Bundesstraße 55, 20146 Hamburg, GermanyMeteorologisches Institut, Fachbereich Geowissenschaften, Centrum für Erdsystem und Nachhaltigkeitsforschung (CEN), Universität Hamburg, Bundesstraße 55, 20146 Hamburg, GermanyDepartment of Space, Earth and Environment, Chalmers University of Technology, 41296 Gothenburg, Swedennow at: European Centre for Medium-Range Weather Forecasts, Shinfield Park, Reading RG2 9AX, UKMax Planck Institute for Solar System Research, Justus-von-Liebig-Weg 3, 37077 Göttingen, GermanyDepartment of Space, Earth and Environment, Chalmers University of Technology, 41296 Gothenburg, Sweden<p>Remote sensing observations at sub-millimeter wavelengths provide higher sensitivity to small hydrometeors and low water content than observations at millimeter wavelengths, which are traditionally used to observe clouds and precipitation. They are employed increasingly in field campaigns to study cloud microphysics and will be integrated into the global meteorological observing system to measure the global distribution of ice in the atmosphere with the launch of the Ice Cloud Imager (ICI) radiometer on board the second generation of European operational meteorological satellites (Metop-SG). Observations at these novel wavelengths provide valuable information not only on their own but also in combination with complementary observations at other wavelengths. This study investigates the potential of combining passive sub-millimeter radiometer observations with a hypothetical W-band cloud radar for the retrieval of frozen hydrometeors. An idealized cloud model is used to investigate the information content of the combined observations and establish their capacity to constrain the microphysical properties of ice hydrometeors. A synergistic retrieval algorithm for airborne observations is proposed and applied to simulated observations from a cloud-resolving model. Results from the synergistic retrieval are compared to equivalent radar- and passive-only implementations in order to assess the benefits of the synergistic sensor configuration. The impact of the assumed ice particle shape on the retrieval results is assessed for all retrieval implementations. We find that the combined observations better constrain the microphysical properties of ice hydrometeors, which reduces uncertainties in retrieved ice water content and particle number concentrations for suitable choices of the ice particle model. Analysis of the retrieval information content shows that, although the radar contributes the largest part of the information in the combined retrieval, the radiometer observations provide complementary information over a wide range of atmospheric states. Furthermore, the combined observations yield slightly improved retrievals of liquid cloud water in mixed-phase clouds, pointing towards another potential application of combined radar–radiometer observations.</p>https://amt.copernicus.org/articles/13/4219/2020/amt-13-4219-2020.pdf |
| spellingShingle | S. Pfreundschuh P. Eriksson S. A. Buehler M. Brath D. Duncan D. Duncan R. Larsson R. Ekelund Synergistic radar and radiometer retrievals of ice hydrometeors Atmospheric Measurement Techniques |
| title | Synergistic radar and radiometer retrievals of ice hydrometeors |
| title_full | Synergistic radar and radiometer retrievals of ice hydrometeors |
| title_fullStr | Synergistic radar and radiometer retrievals of ice hydrometeors |
| title_full_unstemmed | Synergistic radar and radiometer retrievals of ice hydrometeors |
| title_short | Synergistic radar and radiometer retrievals of ice hydrometeors |
| title_sort | synergistic radar and radiometer retrievals of ice hydrometeors |
| url | https://amt.copernicus.org/articles/13/4219/2020/amt-13-4219-2020.pdf |
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