Data User Advisory

Data User Advisory

UPDATE: ENVI HotFix now available. Visit www.exelisvis.com for download instructions.
+ ENVI 5 SP3 Hotfix for Landsat 8
Note: NASA and USGS do not endorse the use of any particular image processing software.
Landsat 8July 24, 2013 • This is a notice for Landsat data users who use ENVI software to process Landsat 8 data. ENVI 5.0 Service Pack 3 (SP3) gives Landsat data users the necessary tools to process Landsat 8 data to TOA reflectance (bands 1–9) and at-satellite brightness temperature (bands 10 and 11). However, due to a metadata file reading issue, ENVI 5.0 SP3 cannot read in the K1 and K2 constants for the Landsat 8 thermal bands; it therefore defaults to Landsat 7 coefficients resulting in brightness temperatures that are slightly off. Additionally, TOA reflectance is currently not accounting for the solar elevation angle. Both of these issues will be corrected via patch to ENVI 5.0 SP3 in the upcoming weeks.
For the thermal bands, the source of the file read error is a change in metadata file format made by USGS. The constants used to be given in the following format: “K1_Constant_Band10 = 774.89” but an extra underscore was added to the Landsat 8 metadata files between “Band” and the thermal band number: “K1_Constant_Band_10 = 774.89”.
At-satellite brightness temperature work around: If you edit the Landsat 8 metadata and remove the extra underscore, ENVI 5.0 SP3 is able to correctly read in the coefficient information and use the correct values. This needs to be done for both the K1 and K2 coefficients. The gain and bias for the Landsat 8 thermal bands work correctly in ENVI 5.0 SP3.
TOA reflectance work around: Use Band Math to divide the TOA Reflectance result by sin(SolarElevationAngle).
Note: NASA and USGS do not endorse the use of any particular image processing software.


On Key

Related Posts

HLS webinar banner

Webinar Recording Available: Advancing Science Capabilities with Data Harmonization & NASA’s Harmonized Landsat Sentinel-2 (HLS) Products

This webinar provides an introduction to HLS data, services, and tools and shows you how to find resources to work with the data; visualize, search for, and access the data through NASA Worldview and Earthdata Search; it also demonstrates how to use the Fire Information for Resource Management System (FIRMS) tool to visualize HLS data to monitor fires and floods.

Read More »
On Key

Related Posts

HLS webinar banner

Webinar Recording Available: Advancing Science Capabilities with Data Harmonization & NASA’s Harmonized Landsat Sentinel-2 (HLS) Products

This webinar provides an introduction to HLS data, services, and tools and shows you how to find resources to work with the data; visualize, search for, and access the data through NASA Worldview and Earthdata Search; it also demonstrates how to use the Fire Information for Resource Management System (FIRMS) tool to visualize HLS data to monitor fires and floods.

Read More »