A summary of the broadscale tropical circulation from 70°E to 180°, for the six months May to October 2000, is presented. Weak La Niña conditions persisted throughout the season. Evidence for this includes continuation of an enhanced upward branch of the Walker circulation over the Australian region, below average atmospheric pressure and above average convection over the summer hemisphere of the region, near-neutral values of the southern oscillation index, a weak and narrow zone of cool sea-surface temperatures in the equatorial eastern Pacific, weak warm sea-surface temperature anomalies in the northwestern Pacific and northern Australia, as well as an active monsoon over Asia. Four major active phases of the 30 to 60-day intraseasonal oscillation were observed, with periodicity apparently fluctuating between about 30 and 50 days. A total of 22 tropical cyclones developed during the period, less than the mean for the area. No cyclones formed in the south Pacific and south Indian Ocean (mean 2.8 ) for the season.
Shaik et al. (Fri,) studied this question.