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Radar Polarimetry for Rain Estimation
very noisy K DP . Further understanding of polarimetric radar measurements can be
found in the literature (Straka et al. 2000; Schuur et al. 2003), which gives detailed
descriptions of the polarimetric characteristics of different scatterers.
An example of polarimetric radar measurements is shown in Figure 13.1. This
is a squall line followed by a large region of stratiform precipitation, which has a
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RH
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NR
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(a) Z H , dBZ
(b) Z DR , dB
(c) ρ HV
(e) Echo class
(d) K DP , ° km
–1
FIGURE  13.1  Example of polarimetric radar measurements (S-band KOUN, 0850UTC,
May 13, 2005, EI = 0.5°): (a) radar reflectivity; (b) differential reflectivity; (c) correlation
coefficient; (d) specific differential phase; and (e) radar echo classification (BD: big drop; RH:
rain/hail mixture; HR: heavy rain; R: moderate/light rain; NR: nonrain echo).