The El Niño event that commenced during 2002 was closely monitored by the Australian Bureau of Meteorology, just as it was throughout the world. Its progress was noted to the public via weekly updates on the Bureau of Meteorology’s climate web pages (www.bom.gov.au/climate), and through formal monthly press releases to the Australian media.

By the end of the Austral winter (June-August 2002), atmospheric and oceanic conditions in the equatorial Pacific had evolved into what many would regard as a weakly warm ENSO (El Niño-Southern Oscillation) state. This gradual progression into warm conditions is supported, for instance, by the Multivariate ENSO index routinely issued by the Climate Diagnostics Center. This index remained below +1 throughout the period, and its value sat well below those observed during the El Niño events of 1997/98 and 1982/83.

Despite this relatively weak beginning to the 2002 El Niño event, the impact upon Australian rainfall and temperature during the same period would appear to have been very strong. Severe rainfall deficiencies were recorded throughout vast tracts of the continent for the 5-months to the end of August. These deficiencies contributed to widespread hydrological drought which wiped an estimated $A6 billion from the annual gross value of Australian farm production.

Comparisons with Australian rainfall patterns from previous El Niño events are presented, along with a general synopsis and analysis of the 2002 El Niño event and its impact upon the Australian climate.