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Landsat-7 ETM+ on-orbit reflective-band radiometric stability and absolute calibration

December 1, 2004

Launched in April 1999, the Landsat-7 Enhanced Thematic Mapper Plus (ETM+) instrument is in its sixth year of operation. The ETM+ instrument has been the most stable of any of the Landsat instruments. To date, the best onboard calibration source for the reflective bands has been the Full Aperture Solar Calibrator, a solar-diffuser-based system, which has indicated changes of between 1% to 2% per year in the ETM+ gain for bands 1-4 and 8 and less than 0.5%/year for bands 5 and 7. However, most of this change is believed to be caused by changes in the solar diffuser panel, as opposed to a change in the instrument's gain. This belief is based partially on vicarious calibrations and observations of "invariant sites", hyperarid sites of the Sahara and Arabia. Weighted average slopes determined from these datasets suggest changes of 0.0% to 0.4% per year for bands 1-4 and 8 and 0.4% to 0.5% per year for bands 5 and 7. Absolute calibration of the reflective bands of the ETM+ is consistent with vicarious observations and other sensors generally at the 5% level, though there appear to be some systematic differences.

Publication Year 2004
Title Landsat-7 ETM+ on-orbit reflective-band radiometric stability and absolute calibration
DOI 10.1109/TGRS.2004.836389
Authors B. L. Markham, K. J. Thome, J. A. Barsi, E. Kaita, Dennis L. Helder, J. L. Barker, Pat Scaramuzza
Publication Type Article
Publication Subtype Journal Article
Series Title IEEE Transactions on Geoscience and Remote Sensing
Index ID 70157498
Record Source USGS Publications Warehouse
USGS Organization Earth Resources Observation and Science (EROS) Center