SACRCOR VAP Released to Evaluation

 
Published: 3 November 2015
Example of gaseous attenuation corrected and masked for significant detection radar reflectivity (top) and dealiased radial Doppler velocity from the Ka-SACR.
This is an example of gaseous attenuation corrected and masked for significant detection radar reflectivity (top) and dealiased radial Doppler velocity from the Ka-SACR.

The ARM Facility is pleased to announce the release of Scanning ARM Cloud Radar (SACR) Corrected Moments (SACRCOR) to evaluation. SACRCOR, developed by the Clouds Research Group at McGill University and modified and implemented by the ARM Facility, provides best-estimate moments from the ARM scanning cloud radars.

First-order corrections include:

  • Accurate separation of the range–height indicator (RHI) scans performed during each scan strategy estimation of range and height corrected for Earth’s curvature and generation of a significant feature mask that isolates cloud and precipitation echoes from instrument noise (note that insects’ echoes may remain).

More complex corrections include:

  • Reflectivity correction for gaseous attenuation, dealiasing of the radial mean Doppler velocity, and second trip echo detection and removal.

SACRCOR data are currently available for X-, Ka-, and W-band scanning radars from the Southern Great Plains, second ARM Mobile Facility deployment to Hyytiälä, Finland, and first ARM Mobile Facility deployment to Cape Cod, Massachusetts, USA.

Scanning modes include:

  • VPT: Vertically pointing.
  • HS-RHI: A sequence of six horizon-to-horizon RHI scans every 30° azimuth that cover the hemispherical sky (360°).
  • CW-RHI: A sequence of multiple horizon-to-horizon range–height indicator (RHI) scans at fixed azimuth perpendicular to the climatological wind direction at the cloud level.
  • AW-RHI: A sequence of multiple horizon-to-horizon range–height indicator (RHI) scans at fixed azimuth parallel to the climatological wind direction at the cloud level.
  • BL-RHI: A sequence of 0-90° elevation range–height indicator (RHI) scans every 2° azimuth to cover a 60° sector.

Note that scanning mode availability varies with site and period of data collection. Also note that scanning mode specification may vary with the site or period of data collection; all relevant information is contained within the VAP file.

All files are made available in CF-radial-complaint netCDF, which can be used with Matlab, IDL, Py-ART, RSL and LROSE/TITAN, and other NCAR tools.

Feedback and use of the data are welcomed and encouraged. For questions or to report data problems, please contact Pavlos Kollias, Jonathan Helmus, or Katia Lamer. Browse the data set here or log in to the ARM Data Archive. (Go here to request an account).

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The ARM Climate Research Facility is a national scientific user facility funded through the U.S. Department of Energy’s Office of Science. The ARM Facility is operated by nine Department of Energy national laboratories.