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Title: Improving Estimation of Specific Differential Phase and Assessing Differential Backscattering Phase
Abstract

Polarimetric variables such as differential phase ΦDPand its range derivative, specific differential phaseKDP, contain useful information for improving quantitative precipitation estimation (QPE) and microphysics retrieval. However, the usefulness of the current operationally utilized estimation method ofKDPis limited by measurement error and artifacts resulting from the differential backscattering phaseδ. The contribution ofδcan significantly influence the ΦDPmeasurements and therefore negatively affect theKDPestimates. Neglecting the presence ofδwithin non-Rayleigh scattering regimes has also led to the adoption of incorrect terminology regarding signatures seen within current operationalKDPestimates implying associated regions of unrealistic liquid water content. A new processing method is proposed and developed to estimate bothKDPandδusing classification and linear programming (LP) to reduce bias inKDPestimates caused by theδcomponent. It is shown that by applying the LP technique specifically to the rain regions of Rayleigh scattering along a radial profile, accurate estimates of differential propagation phase, specific differential phase, and differential backscattering phase can be retrieved within regions of both Rayleigh and non-Rayleigh scattering. This new estimation method is applied to cases of reported hail and tornado debris, and the LP results are compared to the operationally utilized least squares fit (LSF) estimates. The results show the potential use of the differential backscattering phase signature in the detection of hail and tornado debris.

 
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NSF-PAR ID:
10522789
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
American Meteorological Society
Date Published:
Journal Name:
Journal of Applied Meteorology and Climatology
Volume:
63
Issue:
7
ISSN:
1558-8424
Format(s):
Medium: X Size: p. 803-819
Size(s):
p. 803-819
Sponsoring Org:
National Science Foundation
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