USGS EROS Archive - Landsat Archives - Landsat 7 ETM Plus Collection 2 Level-2 Science Products

Science Center Objects

Landsat Collection 2 Level-2 Science Products at a 30-meter spatial resolution can be ordered for Landsat 7 Enhanced Thematic Mapper Collection 2 scenes. (1999-Present)

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Example of the Landsat 7 ETM+ Collection 2 level-2 science products

Example of the Landsat 7 ETM+ Collection 2 level-2 science products. Left: Landsat 7 level-2 surface reflectance image. Right: Landsat 7 level-2 surface temperature image. The data was acquired on August 19, 2020 (path 179 row 28).

(Public domain.)

The U.S. Geological Survey (USGS) offers on-demand production of Landsat 7 Enhanced Thematic Mapper Plus (ETM+) Level-2 Science Products (L2SP) through EarthExplorer. The L2SP include Surface Reflectance (SR) and Surface Temperature (ST) scene-based products.

Surface Reflectance (SR)

Surface Reflectance products provide an estimate of the surface spectral reflectance as it would be measured at ground level in the absence of atmospheric scattering or absorption. The Surface Reflectance products are generated at the Earth Resources Observation and Science (EROS) Center at a 30-meter spatial resolution.

Landsat 7 Surface Reflectance data are generated from the Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS), specialized software originally developed through a National Aeronautics and Space Administration (NASA) Making Earth System Data Records for Use in Research Environments (MEaSUREs) grant by NASA Goddard Space Flight Center (GSFC) and the University of Maryland (Masek et al., 2006). The code applies radiometric calibration and atmospheric correction algorithms to Level-1 Landsat data. Details about Landsat 4-5 Surface Reflectance can be found in the Landsat 4-7 Surface Reflectance Product Guide.

Visit the Landsat Surface Reflectance webpage for documentation and more information

Surface Temperature (ST)

Surface Temperature measures the temperature of the surface of the Earth in Kelvin (K). The Surface Temperature products are generated at the Earth Resources Observation and Science (EROS) Center at a 30-meter spatial resolution.

The Landsat Surface Temperature product is generated from the Landsat Collection 2 Level-1 thermal infrared bands, Top of Atmosphere (TOA) Reflectance, TOA Brightness temperature, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Emissivity Database (GED) data, ASTER Normalized Difference Vegetation Index (NDVI) data, and atmospheric profiles of geopotential height, specific humidity, and air temperature extracted from reanalysis data.

Visit the Landsat Surface Temperature webpage for documentation and more information

Product Availability

The following date ranges apply to the availability of L2SP:

  • Landsat 7 ETM+: July 1999 to Present

Most Landsat 7 Collection 2 Level-2 scenes in the USGS archive can be processed to L2SP If ST cannot be produced, a SR only product is attempted. Landsat Science Products inherit characteristics of the Landsat Collection 1 Level-1 data products. Please note the following caveats:

  • Surface Reflectance is not run for a scene with a solar zenith angle greater than 76°.
  • Users are cautioned against processing data acquired over high latitudes (> 65º) to Surface Reflectance.
  • Due to missing auxiliary input data and/or necessary thermal data, Landsat 7 ETM+ scenes processed May 30 through June 12, 2016, cannot be processed to Surface Reflectance. The order status will be updated with this action and the remaining scenes will continue processing.
  • Landsat 7 ETM+ inputs are not gap-filled in the surface reflectance production. Users can refer to the quality assurance (QA) layers for pixel-level condition and validity flags.
  • Efficacy of Surface Reflectance correction will be likely reduced in areas where atmospheric correction is affected by adverse conditions:
    • Hyper-arid or snow-covered regions
    • Low sun angle conditions
    • Coastal regions where land area is small relative to adjacent water
    • Areas with extensive cloud contamination
  • Landsat atmospheric correction and surface reflectance retrieval algorithms are not ideal for water bodies due to the inherently low level of water leaving radiance, and the consequential very low signal to noise ratio. Similarly, surface reflectance values greater than 1.0 can be encountered over bright targets such as snow and playas.
  • A known error exists in the Landsat Surface Temperature retrievals relative to clouds and possibly cloud shadows. The characterization of these issues has been documented by Cook et al., 2014 (see the Landsat Surface Temperature page for more details).

Additional Information

Algorithm Citation

Access Data

The Landsat Collection 2 Landsat 7 Enhanced Thematic Mapper Plus (ETM+) Level-2 Science Products (Surface Reflectance and Surface Temperature) are available for download from EarthExplorer.

The data are located under the Landsat category, Landsat Collection 2 Level-2 subcategory, as “Landsat 7 ETM+ C2 L2”.

After reviewing the search results and selecting a scene, users will be able to download all bands or select and download selected bands.  The original Landsat scene mapping grid, Universal Transverse Mercator (UTM) or Polar Stereographic (PS), is retained for the L2SP. Note: A compressed .tar file will automatically be created when two or more individual bands are selected.

Digital Object Identifier (DOI)

Collection 2 Landsat 7 Enhanced Thematic Mapper Plus (ETM+) Level-2 Science Product Digital Object Identifier (DOI) number: /10.5066/P9C7I13B