Multiple-wavelength radar perspectives of mixed-phase convective precipitation in MC3E

During the NASA/DOE Midlatitude Continental Convective Clouds Experiment (MC3E), conducted in April-June 2011 near the Southern Great Plains (SGP) site in northern Oklahoma, multiple wavelength aircraft radar observations of a spectra of convective events were collected from ground based scanning and vertically pointing radars and airborne radars. Ground based radars ranged from W to S band (NASA NPOL dual-polarization (S), NASA D3R dual-polarization (Ku/Ka, DOE C-SAPR dual-polarization (C), DOE dual-polarization (X), DOE Ka/W-SACR dual polarization), while the NASA HIWRAP Ku/Ka band Doppler radar flew aboard the NASA ER-2 high altitude aircraft. In-situ microphysics were provided in weak convection from the University of North Dakota Citation aircraft. From an incoherent spaceborne radar perspective, in order to accurately attenuation-correct the profile of radar reflectivity and rainfall rate, it is important to distinguish amongst ice-phase, mixed-phase, and liquid precipitation in convection.

In this study, we will investigate whether height (as is done for the Tropical Rainfall Measuring Mission precipitation radar), temperature, reflectivity, dual-frequency ratio, or other assumptions are best at delineating mixed phase precipitation in convection for application in TRMM and GPM measurements. Using D3R and HIWRAP measurements as a test bed, validation data in the form of spatiotemporally matched data sets from dual-polarization radar variables and hydrometeor identification at longer wavelengths, as well as in situ microphysics data will be used to discriminate mixed phase precipitation zones and as an attenuation reference to examine dual-frequency ratio methods for identification of mixed precipitation and attenuation correction in such zones. Statistical methods for evaluating and correcting single-frequency methods and assumptions in identifying mixed precipitation for TRMM applications will also be discussed.