Landsat Collection 2 Level-2 Surface Reflectance

Landsat Collection 2 Level-2 Surface Reflectance (C2 L2 SR) is the USGS-published atmospherically corrected reflectance product derived from the Landsat 4 through 9 sensor series, spanning a continuous archive from 1982 to present.^[1] The 30 m GSD and 7-band spectral coverage (430 to 2350 nm for OLI/OLI-2; 6 bands 450 to 2350 nm for earlier TM and ETM+) make it the primary input for long-term multispectral land surface change analysis.^[2]

Atmospheric correction uses LEDAPS for Landsat 4 to 7 and LaSRC for Landsat 8 and 9.^[1] This algorithm discontinuity must be accounted for in cross-sensor time series. Landsat 7 ETM+ scenes acquired after May 2003 contain approximately 22 percent data gaps due to the scan line corrector failure; gap-fill is the user's responsibility. The OLI SR product distributes the 7 reflective bands only; panchromatic, cirrus, and thermal bands are excluded.^[2]

Two STAC endpoints provide Collection 2 L2 SR access: the USGS official endpoint at landsatlook.usgs.gov/stac-server (collection id landsat-c2-l2)^[3] and the Microsoft Planetary Computer mirror at planetarycomputer.microsoft.com/api/stac/v1 (same collection id).^[4] All data are freely available under the USGS public domain with no restrictions on use or redistribution.^[5] Processing is constrained to scenes with solar zenith angles below 76 degrees, limiting high-latitude winter coverage.