Apparent absence of the quasi‐biennial oscillation in sea level pressure in the south indian and south atlantic oceans

Abstract

AbstractMonthly mean sea level pressure over the Indian and South Atlantic oceans can be represented adequately by a few uncorrelated pressure fields derived using principal component analysis. Apart from a major, and general, field both zonal and meridional compensatory pressure systems appear to occur over this region of the Southern Hemisphere (approximately 10°W to 60°E and 20.5°S to 40.5°S). the time series of these fields were submitted to spectral analyses, and apart from an oscillation centred at 20 months in the third component there was no evidence suggesting the existence of the quasi‐biennial oscillation in the pressure data. This result conflicts with those for rainfall over southern Africa, and sea level pressure and sea surface temperature around Australia.