Topography, SST anomalies, and precipitation: Unveiling Cyclogenesis in South America

In South America, the extratropical cyclones with the highest destructive potential typically manifest in the southeastern quadrant of the continent—a region encompassing some of the most densely populated centers globally. This study delves into the general characteristics of cyclones developing in the leeward regions of the Andes and those forming near the Atlantic coast, examining their correlation with precipitation in these areas. Our findings indicates that the development of cyclones in these diverse contexts is influenced by topography, local atmospheric circulations, and basin-wide climate oscillations. Furthermore, the analysis uncovers a low-frequency seesaw of coastal and leeward cyclogenesis, wherein ocean temperature differences between basins play a pivotal teleconnectional role.