Trends Between Climate and Lightning Activity and the Impact on Transmission infrastructure

This paper presents an analysis of lightning data from the South African lightning detection network spanning over 15 years from 2009 - 2023. The research consensus is that higher atmospheric temperatures are linked to increased lightning activity. The aim is to investigate correlations between average local temperatures and both lightning stroke density and peak return stroke current. Rising lightning activity and temperature was found to be strongly correlated and is important to consider when designing new infrastructure to meet desired performance targets. Average lightning exposure over long periods (~ 10 years) should be used with caution as this does not capture the significant excursions that were found during the period of analysis due to weather cycles, such as El Niño, in lightning exposure that could result in unexpectedly poor line performance in certain years of high lightning incidence. Lightning data can also be used within a buffer zone around a particular line asset to prioritise remedial and preventative action based on the risk of line faults.