A new MODTRAN-based thermal model for accelerating PLUME TRACKER volcanic emission analysis

Alexander Berk, Vincent Realmuto, Chona Guiang, Rosemary Kennett, Prabhat Acharya, J. Maxwell Riestenberg

Abstract: Plume Tracker (PT), formerly MAP_SO2, is robust, extensively validated, analyst driven software for retrieving gaseous emissions from volcanic releases. While Plume Tracker provides very accurate results, analyzing multispectral imagery typically takes several days of analyst time. The major bottleneck in the PT processing is the relatively slow but accurate FORTRAN-based MODTRAN gas plume and atmospheric radiative transfer (RT) model. This paper describes physics/algorithm based approaches to accelerate the Thermal Infrared (TIR) data analysis of PT analysis by in excess of 100-fold. In particular, we demonstrate that thermal radiance predictions for varying spectral emissivities and surface temperature can be determined from a single MODTRAN run.