Return to Landsat Surface Reflectance Quality Assessment Overview
During Landsat 8-9 OLI/TIRS Surface Reflectance generation, LaSRC assesses the following quality conditions and expresses them using the bands described below. Specific attributes for each band described below are available in the Landsat 8 Surface Reflectance (LaSRC) Product Guide.
sr_aerosol band
LaSRC’s quality conditions are expressed as a confidence level or as either true or false.
- Fill – There are no data values in this pixel.
- Aerosol Retrieval – The retrieval of aerosol measurements was valid in this pixel.
- Water – LaSRC identified this pixel as water.
- Cloud or Cirrus - LaSRC identified this pixel as cloud or cirrus cloud.
- Cloud shadow - LaSRC identified this pixel as cloud shadow.
- Aerosol Retrieval - The retrieval of aerosol measurements was invalid and interpolated from nearby observations.
- Aerosol Content – LaSRC determined the amount of aerosol in this pixel to be climatology-grade, low, medium, or high.
pixel_qa band
This alternative quality assessment algorithm, containing cloud, cloud confidence, cirrus cloud confidence, cloud shadow, snow/ice and water, is generated by the CFMask algorithm and is likely to present more accurate results than the internal tests LaSRC uses for cloud, cloud shadow, snow/ice and water. The Pixel QA band’s quality conditions are expressed as a confidence level or as either true or false.
radsat_qa band
This band is a bit-packed representation of which sensor bands were saturated during data capture, yielding unusable data. The Radiometric Saturation band's quality conditions are expressed as either true or false.
