Tropical cyclones will become more fierce over the next few decades as aIt of global warming. Butmes are unlikely to becomefrequent or spread beyondtropics, according to areport prepared for the WorldMetrological Organization. Thert predicts that the intensityrclones will increase betweennd 20 per cent over the next,.80 years, due to more energeticnpheric convention currents@d by an increase in sea surfacewratures. The report wasared by an international group2 scientists headed by AnnJerson-Sellers, a climatologiste Royal Melbourne Institute ofnolovv, Australia.