Storm tracks and cyclogenesis over the Southern Ocean: An overview with the HadGEM3‐GC3.1 model

Abstract

AbstractExtratropical cyclones play an important role in shaping the weather and climate over vast regions across the globe. To effectively understand and manage the impact of these meteorological events, it is crucial to explore deeper into their structure and behaviour. Here, we have evaluated the characteristics and spatial distribution of extratropical cyclones that had their genesis in the Southern Ocean (SO) in the present climate, based on data from the HadGEM3‐GC3.1‐MM (HG3) global model and the ERA5 reanalysis. Both in winter and summer, cyclone tracks are spatially structured, forming a belt around the entire Antarctic continent, with greater concentration in the SO sector adjacent to the southern Pacific Ocean. The regions of the Somov, Amundsen and Bellingshausen seas exhibited a higher track density of moderate and strong cyclones, indicating a correlation with the strongest baroclinicity in these areas. In both datasets, the maximum occurrence of cyclogenesis was located over the regions of the Somov Sea and the Antarctic Peninsula, making these regions very important in the general configuration of cyclones along the SO. Despite underestimating the total number of cyclones along the SO, the HG3 model showed a good ability to represent the main patterns of cyclonic activity around the Antarctic continent, as well as its average behaviour. Knowing the characteristics and the behaviour of extratropical cyclones in such an important area for global climate is essential for understanding their role in weather and future climate resulting from climate change.