Summary

Description

2ADPR provides single- and dual-frequency-derived precipitation estimates from the Ku and Ka radars of the Dual-Frequency Precipitation Radar (DPR) on the core GPM spacecraft. The output consists of three main classes of precipitation products: those derived from the Ku-band frequency over a wide swath (245 km), those derived from the Ka-band frequency over a narrow swath (125 km), and those derived from the dual-frequency data over the narrow swath. The Ka-band results are further divided into the standard and high-sensitivity estimates. In the standard sensitivity mode, the fields of view within the inner swath are matched to those of the Ku-band. Data from these matched-beam Ku- and Ka-band fields of view are used to derive the dual-frequency precipitation products. The retrievals are performed at each radar range bin along the slant path of the radar instrument field of view (IFOV). The dual-frequency retrieval benefits from having co-aligned measurements at Ku- and Ka-bands. Data from these measurements are used to infer properties of the particle size distribution, which are expected to lead to improved estimates of rainfall rate and equivalent liquid water content. Dual-frequency data are expected to improve the capability to discriminate among water, ice, and mixed-phase hydrometeors as a function of height. This capability is particularly important in convective storms where a bright-band signature, associated with mixed-phase hydrometeors, is usually not detectable. In addition, the different attenuation rates of the Ku- and Ka-bands allow differential attenuation techniques to be used to estimate the path integrated attenuation. The high-sensitivity Ka-band channel is expected to have 6 dB greater sensitivity than the Ku- and standard Ka-band channels and to provide enhanced detection capabilities at the light rainfall rates. ABSTRACT