Future Changes in the Occurrence of Hybrid Cyclones: The Added Value of Cyclone Classification for the East Australian Low‐Pressure Systems.

Several regions of the world, including the east coast of Australia, are characterized by the occurrence of low-pressure systems with a range of different dynamical structures, including tropical, extratropical, and hybrid cyclones. Future changes in the occurrence of cyclones are better understood if storms are classified according to their dynamical structure. Therefore, we apply a classification of cyclones according to their cold-core or warm-core structure to an ensemble of regional climate model simulations. First, we show that historical simulations reproduce well the reanalysis results in terms of cyclone classification. We then show that once cyclone classification is applied, projections of future cyclone activity become more robust, including a decrease in the occurrence of both cold-core and warm-core cyclones. Finally, we show that in a warmer climate warm-core hybrid cyclone activity could increase close to the coast, while the associated rainfall and wind are projected to increase.

Figure 4. Composites at the time of the cyclone lowest central pressure of rainfall and 10-m wind speed fields change between future and historical simulations for all cyclones detected in NARCliM.