Estimating Ice Water Content for Winter Storms from Millimeter-Wavelength Radar Measurements Using a Synthesis of Polarimetric and Dual-Frequency Radar Observations

Journal Article · Wed Jan 01 00:00:00 EST 2025 · Journal of Atmospheric and Oceanic Technology

DOI:https://doi.org/10.1175/JTECH-D-23-0143.1· OSTI ID:3012675

Oue, Mariko ^[1]; Ryzhkov, Alexander V. ^[2]; Matrosov, Sergey Y. ^[3]; Bukovčić, Petar ^[2]; Kollias, Pavlos ^[4]

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1. Stony Brook University, NY (United States)
2. NOAA National Severe Storms Laboratory, Norman, OK (United States); University of Oklahoma, Norman, OK (United States)
3. University of Colorado, Boulder, CO (United States); NOAA Physical Sciences Laboratory, Boulder, CO (United States)
4. Stony Brook University, NY (United States); Brookhaven National Laboratory (BNL), Upton, NY (United States)

The potential of millimeter-wavelength radar-based ice water content (IWC) estimation is demonstrated using a Ka-band Scanning Polarimetric Radar (KASPR) for the U.S. northeast coast winter storms. Two IWC relations for Ka-band polarimetric radar measurements are proposed: one that uses a combination of the radar reflectivity Z and the estimated total number concentration of snow particles N_t and the other based on the joint use of Z, specific differential phase K _DP, and the degree of riming f _rim. A key element of the algorithms is to obtain the “Rayleigh-equivalent” value of Z measured at the Ka band, i.e., the corresponding Z at a longer radar wavelength for which Rayleigh scattering takes place. This is achieved via polarimetric retrieval of the mean volume diameter D_m and incorporating the relationship between the dual-wavelength ratio DWR_S/Ka and D_m. Those techniques allow for retrievals from single millimeter-wavelength radar measurements and do not necessarily require the dual-wavelength ratio (DWR) measurements, if the DWR–D_m relation and Rayleigh assumption for Ka-band K _DP are valid. Comparison between the quasivertical profile product obtained from KASPR and the columnar vertical profile product generated from the nearby WSR-88D S-band radar measurements demonstrates that the DWR_S/Ka can be estimated from the two close radars without the need for collocated radar beams and synchronized antenna scanning and can be used for determining the Rayleigh-equivalent value of Z. As a result, the performance of the suggested techniques is evaluated for seven winter storms using surface disdrometer and snow accumulation measurements.

• Research Organization: University of Colorado, Boulder, CO (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: SC0021160; SC0022163
• OSTI ID: 3012675
• Journal Information: Journal of Atmospheric and Oceanic Technology, Journal Name: Journal of Atmospheric and Oceanic Technology Journal Issue: 1 Vol. 42; ISSN 0739-0572; ISSN 1520-0426
• Publisher: American Meteorological Society
• Country of Publication: United States
• Language: English

Related Subjects

Cloud retrieval
Radars/Radar observations
Snow