A Brewer spectrophotometer was installed at Scott Base in February 1989 to extend the measurements obtained from the Dobson spectrophotometer. The first full season of measurements began in mid-September the following spring. Measurements include the total amount of ozone in the vertical column of the atmosphere from mid-September until the end of February, and during the full moon periods from ... March to September (Raw data = the times and instrument settings for instrument readings, Derived data = column amounts of ozone). Measurements of the vertical distribution of ozone are also possible for six weeks each spring and autumn. The Brewer also simultaneously measures total sulphur dioxide (SO2) The data is submitted to the World Ozone and UV Data Centre, to the Network for the Detection of Atmospheric Composition Change (NDACC) database and to the World Meteorological Organisation (WMO) for use in its Antarctic ozone bulletins.