SACR-ADV-3D3C remaps the outputs of SACRCORR for cross-wind range-height indicator (CW-RHI) scans to a Cartesian grid and reports reflectivity CFAD and best-estimate domain-averaged cloud fraction.
CW-RHI scans consist of multiple consecutive horizon-to-horizon scans (elevations ~10-170°) (Kollias et al., 2014). The CW-RHI scan strategy is typically continuously operated for 25-55 min at the ARM sites.
The major inputs of this VAP are generated by the SACRCORR VAP. They include: Reflectivity corrected for gas attenuation, Unfolded mean Doppler velocity, spectral width, and linear depolarization ratio, all of which are free of noise, insects, and second-trip echo and all of which are in native radar polar coordinates. An additional input is the horizontal wind speed from the nearest (in time) sounding.
These 2D grid slices are used to estimate a reflectivity CFAD. This CFAD contains information for each height about the distribution of reflectivity observed for the duration of the scan strategy (e.g., 19 minutes). A profile of maximum observable domain is reported for user guidance. For completeness, the time coordinate is converted to distance using the sounding horizontal wind speed to provide an estimate of x-y-z cloud fraction.
The 2D grids are also used as an input to a 3D gridding technique. This technique interpolates or extrapolates the 2D grids in time.
The final output is a single NetCDF file containing all aforementioned corrected radar moments remapped on a 3D Cartesian grid, the SACR reflectivity CFAD, a profile of best-estimate cloud fraction, a profile of maximum observable x-domain size (xmax), a profile time-to-horizontal-distance estimate and a profile of minimum observable reflectivity (dBZmin).