Use of Ensembles in Tropical Cyclone Forecasting (#249)
Tropical cyclones are a major natural hazard that affects Australian communities, emergency services, and industries. Ensemble guidance is an integral tool that allows Australian Bureau of Meteorology (ABoM) forecasters, whilst under tight time constraints, to provide skillful and reliable track and intensity forecasts for tropical cyclones.
Ensembles are used in a variety of modes in the tropical cyclone forecast process. One of the more valuable uses of ensembles is to characterise the uncertainty in the position of a tropical system on a particular day. Another is to utilise ensembles to forecast the probability of a system developing into a tropical cyclone. The ensemble forecast track maps are useful tools that allow forecasters to provide alternate scenarios to key stakeholders, thus providing them with information that allows them to make the best decisions.
Tropical cyclone track forecasting is a manual process that can be time intensive. In the future the ABoM forecasters are interested in automating the track and uncertainty area forecasting processes in the tropical cyclone warning centre. The automation of the track and uncertainty forecast process is likely to be a function of the ensemble spread. Investigations will determine the merit of an ensemble, lagged ensemble, or multi-model ensemble approaches.