S. Kalicharran et al., TRENDS IN TOTAL OZONE OVER SOUTHERN AFRICAN STATIONS BETWEEN 1979 AND1991, Geophysical research letters, 20(24), 1993, pp. 2877-2880
Trends in total ozone for the period 1979 to 1991 over the southern Af
rican subcontinent and the southern ocean islands of Marion and Gough
and the South African Antarctic base of SANAE are examined. Version 6
TOMS data are used. With the exception of the low latitude stations (N
airobi and Harare), where a marginally increasing trend (+0.2% and +0.
3%, respectively) was observed, the other stations all exhibited a dec
reasing trend in total ozone over the 13 year period, ranging between
-1.1 and -2.6% over most of South Africa, increasing with latitude to
reach -20.6% at SANAE. Inter-annual fluctuations at Nairobi are domina
ted by a QBO, with maximum ozone occurring during the westerly phase o
f the QBO. At the extratropical locations, ozone peaks and troughs are
anti-correlated with those at Nairobi and the QBO signal is less well
developed and modulated by the seasonal cycle.