Future Stability of U.S. High Plains Land Use

Image Calibration - Airport Calibration

Determining albedo change over time requires knowledge of the sensor calibration and the local atmospheric transmission and path radiance at the time of data acquisition. The Landsat-5 Thematic Mapper sensor has been in orbit since 1984. Although there are onboard calibration lamps for the detectors, no complete optical system calibration is possible. We are investigating the use of airport concrete pads as potentially stable calibration targets for use in inter-year albedo comparisons. The steps are:

• Identify airports that have pads at least 2x2-30 m pixels in size and that exist in images from both years.
• Use the "traveling salesman" algorithm to map out flying routes.
• Contract flights.
• Make measurements using a portable spectrometer and lightsource to take at least 100 spectra of each site.

Airport Measurements: Peter McIntosh taking field measurements using a spectrometer and portable lightsouce (on his right).