Kalisa Egide, Sudmant Andrew
Department of Epidemiology and Biostatistics, Schulich School of Medicine and Dentistry, Western University, London, ON, N6G 2M1, Canada.
Edinburgh Climate Change Institute, University of Edinburgh, High School Yards, Edinburgh, UK.
Sci Rep. 2025 Jul 21;15(1):26448. doi: 10.1038/s41598-025-12210-4.
Mounting evidence demonstrates that heatwaves aggravate urban air pollution, with substantial impacts on public health, but comparatively little research has addressed Sub-Saharan African contexts. In this study, we focused on Kigali, Rwanda, to assess the relationship between extreme heat events and concentrations of fine particulate matter (PM), nitrogen dioxide (NO), and ozone (O) from 2021 to 2024. Using low-cost sensors for dense spatiotemporal coverage, our analysis finds that O concentrations increased significantly during 6 heatwave events with peak values up to 40% higher during heatwaves. Heatwaves also resulted in spikes in PM and NO, however the diurnal and seasonal analyses showed that PM and NO dynamics were shaped more by local emissions than temperature alone. These results highlight the compound risks of heat and air pollution in sub-Saharan African cities, underscoring the importance of early-warning systems and robust urban policies that account for both heat and air pollution. In addition, the atmospheric dynamics identified in this research differ from those observed in many high-income countries, highlighting a critical need for more research exploring the intersection of heat and air pollution in Sub-Saharan Africa.
越来越多的证据表明，热浪会加剧城市空气污染，对公众健康产生重大影响，但针对撒哈拉以南非洲地区情况的研究相对较少。在本研究中，我们聚焦于卢旺达基加利，评估2021年至2024年期间极端高温事件与细颗粒物（PM）、二氧化氮（NO）和臭氧（O）浓度之间的关系。通过使用低成本传感器实现密集的时空覆盖，我们的分析发现，在6次热浪事件期间，O浓度显著增加，热浪期间峰值高达40%。热浪还导致PM和NO浓度飙升，然而，日变化和季节分析表明，PM和NO的动态变化更多地受当地排放影响，而非仅受温度影响。这些结果凸显了撒哈拉以南非洲城市高温和空气污染的复合风险，强调了预警系统和兼顾高温与空气污染的稳健城市政策的重要性。此外，本研究中确定的大气动力学与许多高收入国家观察到的不同，凸显了迫切需要开展更多研究，探索撒哈拉以南非洲地区高温与空气污染的交叉问题。
