The scanning Atmospheric Radiation Measurement (ARM) cloud radars (SACRs)provide continuous atmospheric observations aspiring to capture the 3-Dcloud-scale structure. Sampling clouds in 3-D is challenging due to theirtemporal–spatial scales, the need to sample the sky at high elevations andcloud radar limitations. Thus, a suggested scan strategy is to repetitivelyslice the atmosphere from horizon to horizon as clouds advect over the radar(Cross-Wind Range-Height Indicator – CW-RHI). Here, the processing andgridding of the SACR CW-RHI scans are presented. First, the SACR sampleobservations from the ARM Southern Great Plains and Cape Cod sites arepost-processed (detection mask, gaseous attenuation correction, insectfiltering and velocity de-aliasing). The resulting radial Doppler momentfields are then mapped to Cartesian coordinates with time as one of thedimensions. Next the Cartesian-gridded Doppler velocity fields are decomposedinto the horizontal wind velocity contribution and the vertical Dopplervelocity component. For validation purposes, all gridded and retrieved fieldsare compared to collocated zenith-pointing ARM cloud radar measurements. Weconsider that the SACR sensitivity loss with range, the cloud type observedand the research purpose should be considered in determining the griddeddomain size. Our results also demonstrate that the gridded SACR observationsresolve the main features of low and high stratiform clouds. It isestablished that the CW-RHI observations complemented with processingtechniques could lead to robust 3-D cloud dynamical representations up to25–30 degrees off zenith. The proposed gridded products are expected toadvance our understanding of 3-D cloud morphology, dynamics and anisotropyand lead to more realistic 3-D radiative transfer calculations.
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