Total ozone from NOAA satellites in the Australian region

High Resolution Infrared Radiation Sounder (HIRS) radiance measurements from the TIROS-N/NOAA series satellites have been used to calculate total ozone amounts in real time for the Australian region. The method used to calculate ozone amount has been developed from that of Ma, Smith and Woolf, which is the basis of the algorithms used in the International TOVS Processing Package (ITPP). The method described here employs the radiative transfer equation and uses the statistical relationships between HIRS channel 1 to 4 radiances and ozone amount to establish a first-guess profile. Several changes have been made to the Ma et al., algorithm to improve the estimation of total ozone. Results from the new algorithm are compared with those from the original and with surface-based observations of total ozone taken using Dobson spectrophotometers.