Multispectral sensor data simulation modeling based on the multiple scattering LOWTRAN code

Abstract

A method for simulating satellite channel radiances is described which would be useful for sensor response evaluation and channel optimization studies. Emergent radiance spectra are calculated for wavelengths between 0.4 and 13.0 μm using a modified version of the AFGL LOWTRAN transmittance/radiance code which includes the effects of multiple scattering. These radiance spectra, calculated for a sensor's specific solar illumination condition, are channel bandpass weighted to simulate sensor channel radiance sensitivities to surface—atmosphere properties. This method can produce channel radiances of most earth resources and cloud field multispectral imagers including the Landsat Thematic Mapper (TM) and Multispectral Scanner (MSS), the NOAA Advanced Very High Resolution Radiometer (AVHRR), the GOES Visible Infrared Spin Scan Radiometer (VISSR), the Defense Meteorological Satellite Program's (DMSP) Operational Linescan System (OLS), and Multispectral Operational Linescan System (MSOLS). A variety of realistic remote sensing scenarios are illustrated for selected instruments and fields-of-view containing hazes, fogs, and water and ice clouds observed against surface backgrounds including the ocean surface, land, vegetation, and snow cover. Actual Landsat TM and MSS visible and near infrared data obtained for clear and cloudy fields-of-view are compared to simulated channel radiances to assess the model's accuracy and representativeness.