Operational seasonal predictions in Australia

Neil Plummer
National Climate Centre, Bureau of Meteorology, GPO Box 1289K, Melbourne, Victoria, Australia.
Tel. : +61-3-9669-4457, Fax: +61-3-9669-4760,
E-mail: N.Plummer@BoM.GOV.AU

Following the pioneering work of E.T.Quayle, studies into providing predictions of Australian climate were being performed as early as the 1920s. Comprehensive research on the climatic effects of the El Niño Southern Oscillation phenomenon was renewed in Australia during the 1970s and 1980s and provided the foundations for the predictions in place today. The Bureau of Meteorology has provided a regular Seasonal Climate Outlook service since 1989. Initial predictions were based on simple correlations between the Southern Oscillation Index (SOI) and district rainfall totals but more sophisticated approaches were soon established. Techniques based on multiple linear regression, phases of the SOI, and linear discriminant analysis provided steady improvements. A more recent development has been the use of empirical orthogonal functions to define significant patterns of global sea surface temperature that influence rainfall over Australia.

The basis for seasonal climate outlooks for Australia will be described as well as the diagnostics and techniques on which the predictions are based. Examples of the usefulness of the service to key customer groups will be presented. Future developments will be discussed along with some of the major challenges that will need to be overcome in order to improve the effectiveness of the prediction service.