Quantifying Tropical Cyclones impacting Australia in the late Quaternary using downscaled models

Tropical Cyclones are a dominant feature of the summertime climate over northern Australia. Their passage onto the continent brings severe winds, heavy precipitation and storm surges that have significant impacts on inhabitants lying in their path. Tropical Cyclones that impact Australia form in three genesis regions, the Coral Sea to the north-east of Australia, the western Gulf of Carpentaria, and off the north-west coast of Australia. The present-day climate of Australia experiences up to 20 Tropical Cyclones per year, with an average of 5 of these classified as severe.

The present-day climate of Tropical Cyclones impacting Australia has been widely studied. There has, however, never been analysis of Tropical Cyclones for the palaeoclimate of Australia using down-scaled climate models. Here we present the first analysis of Tropical Cyclones from such modelling. The results presented are from three time slice simulations: mid-Holocene (6 ka), the late Pleistocene (12 ka), and the Last Glacial Maximum (21 ka), compared to a pre-industrial control simulation (1850 CE). The simulations were performed with the Weather Research and Forecasting (WRF) model, downscaled from boundary and initial conditions taken from the Community Earth System Model (CESM).