Articles | Volume 19, issue 1
https://doi.org/10.5194/amt-19-211-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-19-211-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
13 Jan 2026
Research article |
| 13 Jan 2026
| 13 Jan 2026
Hydrometeor partitioning ratios for dual-frequency space-borne and polarimetric ground-based radar observations
Institute of Geosciences, Department of Meteorology, University of Bonn, Bonn, Germany
Kamil Mroz
National Center for Earth Observation, University of Leicester, Leicester, UK
Kai Mühlbauer
Institute of Geosciences, Department of Meteorology, University of Bonn, Bonn, Germany
Silke Trömel
Institute of Geosciences, Department of Meteorology, University of Bonn, Bonn, Germany
Laboratory for Clouds and Precipitation Exploration, Geoverbund ABC/J, Bonn, Germany
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A method for estimating microphysical properties of ice clouds based on radar measurements is presented. The algorithm exploits the information provided by differences in the radar response at different frequency bands in relation to changes in the snow morphology. The inversion scheme is based on a statistical relation between the radar simulations and the properties of snow calculated from in-cloud sampling.
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The article examines the relationship between the characteristics of rain and the properties of the ice cloud from which the rain originated. Our results confirm the widely accepted assumption that the mass flux through the melting zone is well preserved with an exception of extreme aggregation and riming conditions. Moreover, it is shown that the mean (mass-weighted) size of particles above and below the melting zone is strongly linked, with the former being on average larger.
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Short summary
Estimating the proportions of individual hydrometeor types (hydrometeor partitioning ratios, HPRs) in a mixture of a resolved radar volume and their evaluation is challenging. This study has three objectives, (1) to evaluate HPR retrievals, (2) to exploit the combination of dual-frequency (DF) space-borne radar (SR) and dual-polarisation (DP) ground-based radar (GR) observations for estimating HPRs based on SR DF observations and (3) to further improve HPR estimates based on DP GR observations.
Estimating the proportions of individual hydrometeor types (hydrometeor partitioning ratios,...
