Tropical cyclones are influenced by a number of environmental conditions. Cyclones in the Australian region specifically are impacted by the phase of ENSO. Generally, more cyclones make landfall during La Niña years, and fewer during El Niño years.
Analysis of Australian cyclones have limitation due to the short record and the number of changes that has occurred in observing practices. Despite this short record, significant changes have been observed. The number of strong TCs has increased and the storm lifetime peak intensity has migrated southward. If this southward shift continues cities along Eastern and Western Australian coasts could experience tropical TCs more often than in the past, with extratropical transitioning storms also extending their impacts to higher latitudes.
In this paper we investigate how cyclones have changed along the Australian South East coast from Southeast Queensland to the northern parts of New South Wales in recent climate, and what the projected changes are for the next decade. To do this we will examine the changes as simulated by NCAR’s CESM Decadal Prediction Large Ensemble Project (DPLE), which provides more than 20,000 years of simulated data.
We will also use clustering techniques (like Weather Typing) to identify the large-scale environments that are responsible for above average, average, and below average number of tropical cyclones, and investigate how these large-scale environments have changed in the past and will change in the next decade.