Measurement of the Total Ozone Column from Direct Solar Irradiance
Ground level solar irradiance is dependent on various atmospheric parameters such as cloud cover, total ozone and aerosol content. Most of the atmosphere’s ozone is contained in the stratosphere, providing essential protection from the Sun’s harmful UV radiation. Ground-based spectroradiometer measurements of direct solar UV irradiance can be used to determine the Total Ozone Column, TOC . This requires a spectroradiometer capable of tracking the solar zenith angle and measuring spectral irradiance within a narrow field of view. TOC can be determined by applying the Beer-Lambert law in conjunction with the known absorption characteristics of ozone over the 290-350nm wavelength range. Suitable modelling is required to minimise the influences of the other atmospheric attenuators .
The compact BTS2048-UV-S-WP weatherproof UV spectroradiometer is ideally suited for use on sun-trackers to perform direct solar irradiance measurements. During an international inter-comparison  of total ozone measurements the instrument was verified with measurements of direct solar irradiance and subsequent TOC evaluations showing deviations of less than 1.5% to most other reference instruments.
 M. Huber et al., “Total atmospheric ozone determined from spectral measurements of direct UV irradiance,” Geophys. Res. Lett.22, 1995.
 A. Vaskuri et al., “Monte Carlo method for determining uncertainty of total ozone derived from direct solar irradiance spectra: Application to Izaña results”