What exactly is Dual Polarization Radar ? Target (water drop) Vertical Polarization Horizontal Polarization Polarimetric Radars (Dual-Pol) transmit radio wave pulses that have both horizontal and vertical orientations. The additional information from vertical pulses will provide new radar products that will improve forecasts and warnings for hazardous weather.
Dual Polarization RadarMedia Training ZDR ~New Base Radar Products~ Differential Reflectivity (ZDR) -7.9<ZDR<7.9dB Ratio between the reflectivity of the Horizontal pulse and the Vertical pulse. ZDR depends on the shape, and the falling behavior of the particle being sampled. ZDR is positive for rain drops, zero or slightly negative for hail.
Dual Polarization RadarMedia Training CC ~New Base Radar Products~ Correlation Coefficient (CC) 0.0 < CC < 1.0 A statistical correlation between reflected and vertical power returns. Applications include the determination of meteorological vs. non-meteorological echoes. Rain vs. Snow targets, Melting Layer and Tornadic debris.
Dual Polarization Radar Media Training Correlation Coefficient (CC) • 0.0 < CC < 1.0 • Fraction of “perfect” consistency between H & V
Dual Polarization RadarMedia Training KDP ~New Base Radar Products~ Specific Differential Phase (KDP) -2<KDP<10deg/km Comparison of the returned phase difference between the horizontal and vertical pulses. Applications include Heavy Rain determination, Heavy Rain mixed with Hail and Cold vs. Warm Rain processes. KDP really high
Dual Polarization RadarMedia Training ML Antenna wobble and Algorithm error ~New Derived Radar Products~ Melting Layer (ML)
Dual Polarization RadarMedia Training HCA ~New Derived Radar Products~ Hydrometeor Classification Algorithm (HCA)
Dual Polarization RadarMedia Training ~New Derived Radar Products~ Quantitative Precipitation Estimation (QPE) Digital Precipitation Rate (DPR): Displays instantaneous precipitation rates. Gives a good idea of where there is heavy rain falling right now. Digital Accumulation Array (DAA): Similar to the Legacy OHP but with no bias applied. Digital Storm Total Accumulation (DSA): Similar to the Legacy STP product but at a higher resolution but no bias applied (more accurate rainfall accumulation).
Dual Polarization RadarMedia Training Can Dual Pol really show us Tornado Debris?
Dual Polarization RadarMedia Training Dual Polarization is expected to be installed in the NWS Doppler Radar in January, 2013. Training for our media partners is provided by the Warning Decision Training Branch (WDTB) in Norman, OK. Training consists of going through 13 modules on a web site provided to you. The 13 modules cover the 6 new products that Dual Polarization Radar provides.
Dual Polarization RadarMedia Training The training should be completed about 1 month prior to the installation of Dual Polarization at NWS Shreveport Doppler Radar. The web site for the training modules is: http://www.wdtb.noaa.gov/courses/dualpol/ outreach/