Minimize Build L2P Flags Variable

The SLSTR l2p_flags variable, included in SLSTR Level-2 product, holds a code for the SST algorithm used for each pixel:

  • Summary flags, which in most cases are a composite of the nadir and oblique confidence word flags
  • An SST overflow flag, which is set if the SST calculation is valid, but the result exceeds the netCDF range
  • And an exception flag, which is set if any of the contributing brightness temperature pixels are invalid.

The choice of algorithm depends on the atmospheric state and the instrument and solar geometry. In some cases in the product wings, where aerosol or dust contamination is present and only a single view can be used, there is not enough information in the brightness temperatures to fully correct for the contamination signal and no retrieval is attempted.