GIS Ag Maps.org

Southwest Iowa, USA; Landsat 8; path 21 / row 31; July 9, 2017.

Anyone can easily learn how to convert free Landsat 8 imagery to surface reflectance (SR), which can then be used for numerous applications. Simply following the steps in the SR Tutorials on this website, which can be used with GIS software, such as ArcGIS, or free QGIS which can be downloaded off this website. Information necessary to convert the downloads to SR is included on this page is a brief format; the imagery can be easier converted to SR after first completing or reviewing the Landsat 8 ArGIS SR Tutorial or Landsat 8 QGIS SR Tutorial.

LandsatLook Image (RGB 654) for Corresponding Downloads (counties are orange; state boundary is black)

Downloads Background:

The Landsat 8 digital number (DN) downloads below can be converted to the surface reflectance and compared to the USGS SR downloads. This is a simple process after completing or reviewing the Landsat 8 ArGIS SR Tutorial or Landsat 8 QGIS SR Tutorial. USGS Landsat 8 SR is not purely based on dark object subtraction (DOS), it includes landcover, for example - there will be differences.

Graphics are included below the downloads that show the Arc GIS Frequency 50 and QGIS Bin 5 Value. Corresponding USGS Landsat 8 SR Algorithm imagery is included for comparison purposes. Surface reflectance files are in integer format; divide by 10,000 for surface reflectance (for example, 500 = .05 or 5%; 5000 = .5 or 50%). You can convert the DN imagery to SR by applying the steps in the Tutorial and including the image specific Frequency 50 and solar elevation values included below. The extent of the data is the extent of USGS Landsat 8 SR, which is slightly smaller than original DN imagery. Make sure to check for clouds with the Cloud Detection downloads, as well as the QB image. Band 5 can be used for cloud shadow detection.

IMPORTANT: MAJOR INTERNET BROWSERS HAVE RECENTLY UPGRADED SECURITY FOR DOWNLOADING DATA FROM WEBSITES. If your browser has a security risk message when attempting to download a file below (or any file on this website), you can complete a download security risk check by: 1) copying the download URL by right-clicking on the download then clicking Copy Link, 2) accessing virustotal.com (parent company is Google; opens in new tab) then clicking the URL tab, 3) pasting the download URL into the search box then clicking the magnifying glass to start the download security risk search. Of course, use the download security check website or tool of your choice.