Spectral Calibration for SO2 Cameras with Light Dilution Effect Correction

The detection ability of SO2 cameras has been improved effectively, while the calibration is still main factor that limits their measurement accuracy. This paper presents a nonlinear theory by considering effect light dilution due to path radiance as well dependence plume aerosol on scattering wavelength. new spectral method used retrieve column density and emission rate Etna volcano. Results show that, compared with DOAS approach, inversion error can be reduced 13% if adopted. superiority proposed will become more obvious for long-distance optically thick plumes.