scholarly journals Effect of Natural Variations in Rain Drop Size Distributions on Rain Rate Estimators of 3 cm Wavelength Polarimetric Radar

2005 ◽  
Vol 83 (5) ◽  
pp. 871-893 ◽  
Author(s):  
Masayuki MAKI ◽  
Sang-Goon PARK ◽  
V.N. BRINGI
Keyword(s):  
Drop Size ◽  
Rain Rate ◽  
Size Distributions ◽  
Polarimetric Radar ◽  
Rain Drop ◽  
Natural Variations ◽  
Drop Size Distributions

Drop deformation estimate with multi-polarization radar

2020 ◽  
Vol 12 (9) ◽  
pp. 870-877
Author(s):  
Yuliya Averyanova ◽  
Anna Rudiakova ◽  
Felix Yanovsky
Keyword(s):  
Drop Size ◽  
Mathematical Expression ◽  
Microwave Remote Sensing ◽  
Radar Signal ◽  
Drop Deformation ◽  
Size Distributions ◽  
Polarimetric Radar ◽  
Energy Redistribution ◽  
Drop Size Distributions ◽  
Radar Antenna

AbstractThis paper considers the ability of polarization measurements for microwave remote sensing of clouds and precipitation. The simulation of reflections from liquid hydrometeors with a multi-polarization radar system is presented. The mathematical expression of energy received by a radar antenna with arbitrary polarization is obtained. The simulation of the energy redistribution of the signal reflected from liquid hydrometeors assembled over the antennas of multi-polarimetric radar for different wind conditions and different drop-size distributions is obtained and analyzed. The simulation results demonstrate the possibility to register wind and wind-related phenomena by polarimetric radar. The results of the paper can also be used to exclude an impact of drop vibration or oscillation into the radar signal to eliminate errors and underestimation during parameter measurements. The approach to segregate the reflected signal magnitude variations due to the wind-related phenomena from other factors is discussed.

Observed Bulk Hook Echo Drop Size Distribution Evolution in Supercell Tornadogenesis and Tornadogenesis Failure

2021 ◽  
Author(s):  
Kristofer S. Tuftedal ◽  
Michael M. French ◽  
Darrel M. Kingfield ◽  
Jeffrey C. Snyder
Keyword(s):  
Drop Size ◽  
Thermodynamic Characteristics ◽  
Radar Data ◽  
Number Concentration ◽  
Size Distributions ◽  
Polarimetric Radar ◽  
Dual Polarization ◽  
Near Surface ◽  
Microphysical Processes ◽  
Drop Size Distributions

AbstractThe time preceding supercell tornadogenesis and tornadogenesis “failure” has been studied extensively to identify differing attributes related to tornado production or lack thereof. Studies from the Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX) found that air in the rear-flank downdraft (RFD) regions of non- and weakly tornadic supercells had different near-surface thermodynamic characteristics than that in strongly tornadic supercells. Subsequently, it was proposed that microphysical processes are likely to have an impact on the resulting thermodynamics of the near-surface RFD region. One way to view proxies to microphysical features, namely drop size distributions (DSDs), is through use of polarimetric radar data. Studies from the second VORTEX used data from dual-polarization radars to provide evidence of different DSDs in the hook echoes of tornadic and non-tornadic supercells. However, radar-based studies during these projects were limited to a small number of cases preventing result generalizations. This study compiles 68 tornadic and 62 non-tornadic supercells using Weather Surveillance Radar–1988 Doppler (WSR-88D) data to analyze changes in polarimetric radar variables leading up to, and at, tornadogenesis and tornadogenesis failure. Case types generally did not show notable hook echo differences in variables between sets, but did show spatial hook echo quadrant DSD differences. Consistent with past studies, differential radar reflectivity factor (ZDR) generally decreased leading up to tornadogenesis and tornadogenesis failure; in both sets, estimated total number concentration increased during the same times. Relationships between DSDs and the near-storm environment, and implications of results for nowcasting tornadogenesis, also are discussed.

scholarly journals Comparison of simultaneous rain drop size distributions estimated from two surface disdrometers and a UHF profiler

2000 ◽  
Vol 27 (12) ◽  
pp. 1763-1766 ◽  
Author(s):  
Christopher R. Williams ◽  
Anton Kruger ◽  
Kenneth S. Gage ◽  
Ali Tokay ◽  
Robert Cifelli ◽  
...  
Keyword(s):  
Drop Size ◽  
Size Distributions ◽  
Rain Drop ◽  
Drop Size Distributions

scholarly journals On the Realism of the Rain Microphysics Representation of a Squall Line in the WRF Model. Part II: Sensitivity Studies on the Rain Drop Size Distributions

2019 ◽  
Vol 147 (8) ◽  
pp. 2811-2825 ◽  
Author(s):  
Céline Planche ◽  
Frédéric Tridon ◽  
Sandra Banson ◽  
Gregory Thompson ◽  
Marie Monier ◽  
...  
Keyword(s):  
Drop Size ◽  
Wrf Model ◽  
Melting Process ◽  
Squall Line ◽  
Size Distributions ◽  
Line System ◽  
Stratiform Region ◽  
Rain Drop ◽  
Vertical Evolution ◽  
Drop Size Distributions

Abstract A comparison between retrieved properties of the rain drop size distributions (DSDs) from multifrequency cloud radar observations and WRF Model results using either the Morrison or the Thompson bulk microphysics scheme is performed in order to evaluate the model’s ability to predict the rain microphysics. This comparison reveals discrepancies in the vertical profile of the rain DSDs for the stratiform region of the squall-line system observed on 12 June 2011 over Oklahoma. Based on numerical sensitivity analyses, this study addresses the bias at the top of the rain layer and the vertical evolution of the DSD properties (i.e., of Dm and N0*). In this way, the Thompson scheme is used to explore the sensitivity to the melting process. Moreover, using the Thompson and Morrison schemes, the sensitivity of the DSD vertical evolution to different breakup and self-collection parameterizations is studied. Results show that the DSDs are strongly dependent on the representation of the melting process in the Thompson scheme. In the Morrison scheme, the simulations with more efficient breakup reproduce the DSD properties with better fidelity. This study highlights how the inaccuracies in simulated Dm and N0* for both microphysics schemes can impact the evaporation rate, which is systematically underestimated in the model.

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