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  • Analysis of the microphysical properties of snowfall using scanning polarimetric and vertically pointing multi-frequency Doppler radars
Title: Analysis of the microphysical properties of snowfall using scanning polarimetric and vertically pointing multi-frequency Doppler radars
Abstract. Radar dual-wavelength ratio (DWR) measurements from the Stony Brook RadarObservatory Ka-band scanning polarimetric radar (KASPR, 35 GHz), a W-bandprofiling radar (94 GHz), and a next-generation K-band (24 GHz) micro rainradar (MRRPro) were exploited for ice particle identification using triple-frequency approaches. The results indicated that two of the radarfrequencies (K and Ka band) are not sufficiently separated; thus, thetriple-frequency radar approaches had limited success. On the other hand, ajoint analysis of DWR, mean Doppler velocity (MDV), andpolarimetric radar variables indicated potential in identifying ice particletypes and distinguishing among different ice growth processes and even inrevealing additional microphysical details. We investigated all DWR pairs in conjunction with MDV from the KASPRprofiling measurements and differential reflectivity (ZDR) and specificdifferential phase (KDP) from the KASPR quasi-vertical profiles. TheDWR-versus-MDV diagrams coupled with the polarimetric observables exhibiteddistinct separations of particle populations attributed to different rimedegrees and particle growth processes. In fallstreaks, the 35–94 GHz DWRpair increased with the magnitude of MDV corresponding to the scatteringcalculations for aggregates with lower degrees of riming. The DWR valuesfurther increased at lower altitudes while ZDR slightly decreased,indicating further aggregation. Particle populations with higher rimedegrees had a similar increase in DWR but a 1–1.5 m s−1 largermagnitude of MDV and rapid decreases in KDP and ZDR. The analysisalso depicted the early stage of riming where ZDR increased with theMDV magnitude collocated with small increases in DWR. This approach willimprove quantitative estimations of snow amount and microphysical quantitiessuch as rime mass fraction. The study suggests that triple-frequencymeasurements are not always necessary for in-depth ice microphysical studiesand that dual-frequency polarimetric and Doppler measurements cansuccessfully be used to gain insights into ice hydrometeor microphysics.  more » « less
Award ID(s):
1841246 1841215
PAR ID:
10316690
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Atmospheric Measurement Techniques
Volume:
14
Issue:
7
ISSN:
1867-8548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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