equatorial Pacific Ocean temperatures have
continued to warm over the past two weeks, and are now at their highest levels
since at least the El Niño event of 2002. Similarly, the 30-day Southern
Oscillation Index is lower than at any time since 2005. Leading climate models
suggest tropical ocean temperatures will remain above El Niño thresholds into
the first quarter of 2010.
sustained weakening of the Trade Winds during October and early November
enabled central Pacific equatorial temperatures to rise up to 2°C above normal.
However, average to stronger than average Trade Winds currently over the
western Pacific may curtail any further warming during the next fortnight. The
distribution of Tropical cloud has similarities to the patterns observed in the
2002 and 2006 El Niño events, while recent rainfall patterns over Australia are
typical of mature El Niño conditions.
a warming of the oceans to Australia’s
northwest over the past week, the Indian Ocean Dipole (IOD), as measured by the
Dipole Mode Index (DMI), is neutral. The Bureau’s POAMA model suggests neutral
IOD conditions will persist over the coming months.