Community Satellite Processing Package

NOAA Clouds from AVHRR Extended (CLAVR-x) Retrieval Software Package in Support of VIIRS, MODIS and AHVRR Version 1.0

16 May 2014

First release of the US National Oceanic and Atmospheric Administration (NOAA) software for transforming direct broadcast Suomi-NPP VIIRS Sensor Data Records (SDRs), NOAA-18, NOAA-19, MetOP-A and MetOP-B AVHRR, and Aqua and Terra MODIS Level-1B (L1B) files into Level 2 cloud products. CLAVR-x is NOAA's operational cloud processing system for the AVHRR, and it's cloud algorithms are scheduled to migrate to the operational processing system for NOAA JPSS.

CLAVRx software produces single Field-of-View (FOV) cloud retrievals in HDF4 format from input AVHRR, MODIS, and VIIRS Imager calibrated/geolocated data files. A few key output parameters are listed below:

  • cloud mask,
  • cloud type (13 categories),
  • cloud height,
  • cloud top pressure,
  • cloud top temperature,
  • cloud emissivity,
  • cloud optical depth,
  • cloud effective radius,
  • cloud phase,
  • product quality flags.
Other parameters, including ocean, land and aerosol products are also retrieved. Please see the documentation provided in the package for a complete list of products and a description of the retrieval algorithms. CLAVR-x source code is included with this release.

The software is supported on 64 bit linux platforms.