Data from the Total Ozone Mapping Spectrometer (TOMS) on the Nimbus 7 satellite are compared with Dobson spectrophotometer measurements from the Antarctic, where a large decrease in October total ozone has been observed over the last decade. It has hypothesized that the decrease is caused by local photochemical effects of man-made chlorofluorocarbons. The TOMS data, which start in 1978, agree well with the Dobson data, confirming the low values of recent years. However, during the southern hemisphere spring total ozone in the Antarctic is strongly affected by transport associated with the breakdown of the stratospheric vortex. The strength and timing of the vortex breakdown are highly variable and can have a large effect on monthly-mean total ozone values. The TOMS data suggest that variations in the stratospheric circulation have contributed to the long-term decrease. Large variations in total ozone are not confined to the Antarctic. Zonal-mean ozone values have also decreased in the northern hemisphere spring during the TOMS observing period.