SCIENCE OF SEASONAL CLIMATE PREDICTION

Climate change and seasonal predictions
by Ian Smith, CSIRO Marine and Atmospheric Research, Water for a Healthy Country Flagship Program

Dr Ian Smith is a Principal Research Scientist within the CSIRO Climate, Weather and Ocean Prediction Theme. His research includes modelling and diagnostic studies of Australian climate drivers, seasonal and multi-seasonal forecasting using a variety of methods, and the assessment of skill and value of forecasts. He is a coordinator of CSIRO’s contribution to the Indian Ocean Climate Initiative (IOCI) research program, coordinator of the South East Australian Climate Initiative (SEACI) program on seasonal predictions, contributor to the Antarctic Climate and Ecosystems Cooperative Research Centre and an Honorary Research Fellow with The University of Melbourne.

The main source of seasonal predictability in the Australian region is related to variability associated with ENSO (El Niño Southern Oscillation) events. Climate change may affect these events in terms of frequency, duration, amplitude, phase locking to the seasonal cycle and the response of the hydrological cycle (Smith et al. 1997). A brief overview is presented of recent studies (eg. Cane, 2005) which address this issue. These studies also indicate deficiencies in our understanding and ability to model ENSO events and point to priority research areas that need attention. Finally, the existence of significant trends in Australian seasonal rainfall over recent years (Smith, 2004) suggests that current baselines are likely to be inappropriate. An example is presented which indicates how this could affect current seasonal
rainfall outlooks.

References