Sensitivity Studies on Sulfur Dioxide Measurements with Satellite-Borne Solar Backscattered Ultraviolet Spectrometer

The Ozone and Pollution measuring Ultraviolet Spectrometer (OPUS) is scheduled to launch on board the GCOM A I satellite, to measure ozone, sulfur dioxide (SO2), nitrogen dioxide (NO2) and other chemical species including aerosols. OPUS measures the backscattered ultraviolet radiance with the wavelength step of 0.5nm in ultraviolet - near infrared regions. This wavelength step is coarse compared with that of GOME, but it was found that this difference do not substantially affect the uncertainty in SO2 estimation. Simulation study using the radiative transfer code of MODTRAN reveals that the wavelength range of 310-320 nm was found to be sensitive for SO2 detection in case of solar backscattered radiation measurements from space. We wilt present the estimation method of total column SO2 amount from the backscattered radiance observed with the OPUS, using the fine structure Of SO2 absorption spectrum.