The Impact of Climate Change on Road Traffic Crashes in Ghana

TL;DR

This study explores how climate change, particularly rainfall patterns, affects road traffic crashes in Ghana, emphasizing the need for weather-specific road safety measures.

Contribution

The study is the first to combine quantitative and qualitative methods to assess climate change's impact on road traffic crashes in Ghana.

Findings

Rainfall during the wet season is strongly linked to increased crash severity across all regions in Ghana.

Causal inference analysis showed rainfall has a 3.59% stronger influence on fatal crashes than temperature during the wet season.

Stakeholders reported observed changes in rainfall patterns affecting road safety, especially during the rainy season.

Abstract

Despite the substantial injuries and fatalities from Road Traffic Crashes (RTCs), evidence of climate change's impact on RTCs in Ghana is lacking. This study assessed the impact of climate change on RTCs in Ghana by combining quantitative (Mann-Kendall trend tests, Continuous Wavelet Transform analysis, causal inference analysis) and qualitative (15 key stakeholder interviews) methods. The quantitative analysis employed monthly rainfall and temperature data (1991–2021) alongside RTC data (1998–2021) across 10 regions. While rainfall trends varied regionally, the wet season (April through mid-October) showed a strong link to crash severity for all regions across Ghana. Wavelet analysis showed higher crash severity in the wet season within every 2–8 months period in a particular annual year during the study period. Causal inference analysis revealed rainfall's stronger influence (3.59%) on fatal crashes during the wet season compared to temperature (0.04%). Key stakeholder interviews highlighted perceived changes in temperature and intense rainfall patterns affecting RTCs, especially during rainy seasons suggesting an association between increased rainfall and crash severity. These findings emphasize the multifaceted role of climate change on road safety and the need to address weather-specific risks.