Assessing the Spatio-Temporal Effects of Climate-Related Extreme Weather Events on South African Railway Infrastructure

The consequences of changing climate conditions and associated extreme weather are increasingly discussed in the global railway transport sector, as infrastructure damage and service disruptions are more widely reported. The Passenger Rail Agency of South Africa (PRASA) is a critical component of the national passenger rail service that provides safe, reliable and affordable rail services to millions of passengers annually. However, the increasing recorded frequencies of extreme weather events in the country means that PRASA’s operations and infrastructure are not exempt from these emerging hazards. This provided an opportunity for the study to assess the spatio-temporal exposure and climate risk of climate-related extreme weather events to PRASA infrastructure and operations. The study drew on the strengths of a mixed-methods approach, integrating quantitative and qualitative techniques. It combined recorded historical extreme-weather event data from the South African Weather Service (SAWS) with expert-based focus group discussions to address the research questions. Findings show an increase in the recorded frequency of extreme weather events over a period of 103 years (1920–2022) in both areas. These hazards indicate exposure that can lead to damage to physical rail infrastructure and to train service disruptions. In both areas, Kendall’s tau indicated significant positive monotonic trends in the frequency of several weather-related hazards over time. Focus group findings identified coastal flooding, flash floods and sea-level rise as the top priority climate-related risks for PRASA along other key infrastructure vulnerabilities. On this basis, the study recommends both rail infrastructure and operational adaptations.