CANCELED – [PAOCQ] Dan Westervelt (Columbia LDEO)

In Africa, air pollution exposure has been linked to 1.1 million premature deaths annually and, without intervention, these numbers are likely to climb. Sparse pollutant monitoring across the continent makes these estimates uncertain and also hinders the development of mitigation policies and regulations. Additionally, some of the most severe climate impacts are also felt in Africa, despite the continent’s relatively small contribution to global greenhouse gas emissions. This talk will highlight some recent efforts to close the air pollution data gap in Africa using a variety of methods spanning from traditional reference monitors, to consumer-grade low-cost sensors, to satellite retrievals, and to air quality and climate models. In particular we demonstrate the effectiveness of well-calibrated low cost particulate matter sensors in several previously-unmonitored megacities including Kinshasa (DRC), Lomé (Togo), Accra (Ghana), Nairobi (Kenya), and more. These well-calibrated sensors form the basis of dense urban networks of PM2.5 monitors in several African megacities, for example in Kinshasa (DRC), where the annual mean PM2.5 in 2019 was approximately 45 µg m-3, or ~8 times the WHO annual guideline. Finally, I will present climate modeling results that quantify how both local and remote aerosol emissions changes can have a substantial impact on African climate, in particular rainfall in the drought-stricken Sahel region of Africa.