“Changing weather systems over southern Africa”

The prosperity and economic growth of southern Africa is inextricably linked to its rainfall climate, and southern Africa is one of the few regions of the world where models agree that annual rainfall will decrease in response to climate change. Despite this, the weather systems that form the basic building blocks of the region’s climate are chronically understudied. In this talk, we will review recent work into key precipitating weather systems that drive rainfall over southern Africa: tropical lows and the Congo Air Boundary (CAB). By applying objective algorithms to track these systems through climate model output and reanalysis data, we can construct future projections of how these weather systems may change in the future, and how this change drives the projected precipitation decline. We will find that the CAB is projected to become more frequent and to shift northwards in a warmer climate, driving a delay in wet season onset, and that model difficulties in simulating tropical lows contributes to diversity in summer rainfall projections.