Due to larger multiple scattering effects in the troposphere compared to that in the stratosphere, the optical path of tropospheric ozone is markedly enhanced (as compared with that of stratospheric ozone) in the Huggins bands from 310 to 345 nm. Model study of the direct and diffuse solar fluxes on the ground shows differences between tropospheric and stratospheric ozone. The characteristic signature of tropospheric ozone enables us to distinguish a change in troposheric ozone from that of stratospheric ozone. A simple retrieval algorithm is used to recover the tropospheric column ozone from simulated data.