Thermal remote sensing observations and their use in estimating the impact of landscape fire emissions on air quality and population mortality Seminar

Airborne fine particulate matter (PM _2.5 ) represents the greatest ambient air pollution risk to health and ‘landscape’ fires are a significant PM _2.5 source in many regions worldwide. This talk discusses the application of satellite thermal measurements of actively burning fires to estimate smoke emissions and their use in the Copernicus Atmospheric Monitoring System (CAMS). The latter is used to investigate patterns of global population exposure to ambient surface level PM _2.5 , and to the contribution estimated from landscape fires. The air quality impact and annual average mortality are calculated at national level, which highlights both the burden of poor air quality and the significance of landscape fire sources in developing nations in particular.

Over 140 countries to have an average population weighted (PW) total PM _2.5 surface level concentration exceeding the 10 µg.m ^-3 guideline recommended by WHO, with 67.2 million people annually exposed to PM _2.5 levels classed as ‘hazardous’ (> 250.5 µg.m ^-3 ) according to the US Environmental Protection Agency (EPA) air quality index (AQI). Landscape fires alone result in 44 million people annually being exposed to air quality considered unhealthy (PM _2.5 > 55 µg.m ^-3 ), and 4 million to that considered ‘hazardous’ to health (> 250.5 µg.m ^-3 ). Populations in central and west Africa and south and south east Asia are most affected by the landscape fire smoke. Combining published dose-response functions with these landscape-fire PM _2.5 contributions, it is estimated that 670,000 premature deaths annually result from exposure to fire smoke, with a large percentage being children under five. This represents between 8 and 21% of the estimated 3.2 to 8.9 million people dying annually from outdoor air pollution exposure, highlighting landscape fires as a significant contributor.

Speaker Information

Dr Gareth Roberts - Lecturer in Remote Sensing within Geography and Environmental Science at the University of Southampton.