How do winter-time extratropical cyclones change in the future over South Africa?

Extratropical cyclones (ETCs) in South Africa usually occur during the winter (June to August), specifically influencing the Western Cape, causing extreme rain and strong winds. We investigate future changes in these winter-time ETCs using the simulations from three CORDEX-CORE Africa models. Each of these models was driven by three Coupled Model Intercomparison Project phase 5 (CMIP5) General Circulation Models (GCMs), resulting in nine sets of simulations. The simulations are from 1970-2100, with scenarios starting from 2006. We identified the cyclone tracks using the Hodges tracking algorithm, which used 6-hourly relative vorticity data at 850 hPa level. We chose a 20-year historical period from 1986 to 2005 for comparison with a future period of the same length from 2080 to 2099, focusing on the Representative Concentration Pathway (RCP) 8.5 scenario for the future projections. We observed a projected decrease in the number of ETCs in the future. The average track distance and duration are also projected to reduce. These reductions are statistically significant. We explored the future changes in the ETC-associated rainfall, which is also projected to be reduced in the future. We are currently looking at extending our analysis with the high-resolution 4 km gridded Climate Predictions for Africa (CP4A) data and see how our earlier results compare with the high-resolution data.