An uncontrolled thermographic mosaic, which covers most of the area of Yellowstone National Park, has been compiled. The recording of aerial thermographic data on videotape is established as one of the prerequisites for the preparation of more accurate mosaics. Post-mission processing of the videotape record can rectify the nadir line to a topographic map base, correct for v/h variations in adjacent flight lines, correct for yaw distortions, rectify distortions caused by pitch, and rectify distortions produced by non-linearity of the side-wise scan. Installation of a thermal infrared scanning radiometer in a gyrostabilized mount and post-mission processing of the videotape record (principally rectification of side-wise scan distortion) would yield a controlled, photogrammetrically accurate thermographic mosaic. However, the techniques used in the preparation of the uncontrolled thermographic mosaic of Yellowstone National Park can be immediately applied to the preparation of regional thermographic mosaics, important to geologists and other scientists and engineers in studies of geothermal and volcanic areas, and to other types of environmental investigations such as pollution studies of large water bodies (e.g., harbors, estuaries, lakes, etc.), where a precise planimetric image is not critical.
