The Guy Carpenter Asia-Pacific Climate Impact Centre (GCACIC) at City University of Hong Kong has embarked on the development of real-time predictions of the annual number of tropical cyclones (TCs) affecting the Australian region (90°E-160°E, 40°S-0°N) (NA) and its subregion (western Australian region, 90°E-135°E, 40°S-0°N) (NWA). Hindcasts for the period of 1983-2008 have shown that the predictions are mostly correct within the error bars.
These are all statistical predictions with predictors drawn from a large group of indices that represent the atmospheric and oceanographic conditions during the pre-season. The most prominent ones include the proxies for the El Niño/Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD). It should also be noted that predictions for the eastern Australian region are not made at this point because of the difficulty in identifying significant predictors. Further investigation will be necessary in this area and results will be reported in the future.
Starting from the 2009/10 season, we will attempt to issue real-time forecasts of NA and NWA. These should be considered as experimental forecasts and verifications will be made after each season. A more thorough evaluation of the performance of the prediction equation will be made in a few years.