A Global Climatology of Total Ozone from the Nimbus-7 Total Ozone Mapping Spectrometer

Summary

A global climatology of total column ozone was computed from four years of daily observations by the Total Ozone Mapping Spectrometer (TOMS) aboard the NIMBUS-7 satellite. The precision of the TOMS retrievals with respect to well-maintained Dobson instruments is ~2% (1). The TOMS retrievals average 6% lower than the Dobson measurements. The bias is largely explained by differences in the ozone absorption coefficients used with the different instruments (1). Global maps of the time-mean total ozone and the amplitude, phase, and fraction of the variance explained by the annual and semiannual harmonics were prepared. Similar analyses of the zonal-mean total ozone were carried out.