Geometric Calibration Updates to Landsat 7 ETM+ Instrument for Landsat Collection 2 Products

The Landsat 7 (L7) spacecraft and its instrument, the enhanced thematic mapper plus (ETM+), have been consistently characterized calibrated since launch in April of 1999. These performance metrics calibration updates are determined through U. S. Geological Survey (USGS) image assessment system (IAS), which has performing this function launch. Starting 2016, USGS adopted a tiered collection management structure for data products that ensures consistent method processing archive within given while allowing set to be performed between any two collections. time frame 2016 end 2020 was part Collection 1, middle start 2 products. initiates reprocessing archive, may involve one or more updated parameters, improvements support needed product generation, improved algorithms used both flow along with characterization instruments spacecraft. This paper discusses only ETM+ geometric instrument 2. Three were made ETM+; thermal band odd-to-even detector alignment, sensor attitude control (ACS) cold-to-warm focal plane alignment adjustment. impact accuracy systematic terrain (L1GT), generated before applying corrections based on ground registration. changes impacted bands 5, 6, plane. Other updates, such as scan mirror done routine basis not due their dynamic characteristics.