Accuracy of atmospheric correction algorithm using ATM data

Abstract

An atmospheric correction algorithm has been formulated for remotely sensed data collected from a variable altitude of the sensor. Thus, the algorithm is applicable to the satellite-borne sensor data as well as to the airborne sensor data. It has been applied to the airborne thematic mapper (ATM) data collected from two altitudes over a pre-selected test site and the data from two altitudes (from 4000 m and 800 m during the Spring phase and from 3600 m and 800 m during the Autumn phase) were aquired within 15min time interval. The aim of this project was to assess the accuracy of atmospheric correction algorithm by comparing surface spectral reflectances resulting form two altitudes data. If the atmospheric effects are ignored then within the visible domain the refleclanccs of the Earth-atmosphere system from two altitudes differ by as much as 400 per cent. After the application of atmospheric correction the differences in spectral reflectances from two altitudes are mostly within 15 to 20 per cent, the reflectances from higher latitudes data being consistently lower than the reflectances from lower altitude (800 m) data.