Climate and Atmospheric Science (ICAS) PhD Projects
Quantifying public health risk from European air pollution under future climate change
Supervisors: Dr Steve Arnold (SEE) & Dr Dominick Spracklen
Surface ozone and particulate matter (PM) are two major contributors to poor air quality worldwide. Ozone is formed in-situ in the atmosphere from nitrogen oxides (primarily emitted from motor vehicles and power generation) and volatile organic compounds (emitted from both man-made industrial sources and naturally by vegetation). PM has a myriad of both primary emission sources (e.g., motor vehicles, industry), but it can also be produced in-situ in the atmosphere from gas-phase precursors, such as sulphur & nitrogen oxides and organic compounds. Studies suggest that climate warming in an enhanced CO2 future may lead to increases in abundance of ozone and PM pollutants in Europe, offsetting efforts to reduce their concentrations through local emission controls. Under a warmer climate, there are a number of processes that may lead to poorer air quality. A warmer climate may increase the incidence of high pressure events and stagnation of air masses (e.g. Mickley et al., 2000), natural emissions from vegetation increase non-linearly with temperature (Guenther et al., 1995), warmer temperatures change chemical reaction rates in the atmosphere, a warmer climate may increase the frequency and intensity of wildfires (e.g. Spracklen et al., 2009), and changes in temperature and precipitation affect the loss of gas-phase species (such as ozone) to the surface in dry deposition. The European heatwave of 2003 has been viewed as a proxy for European summertime conditions under a warmer climate. During this event, it is estimated that ozone and PM exposure resulted in between 423 and 769 excess deaths in England over 14 days (Stedman, 2004), representing up to 40% of the excess mortality, and between 400-600 excess deaths in the Netherlands (Fischer et al., 2004). An increase in the incidence and intensity of such events may have potentially serious implications for human health and mortality, however the likelihood of their occurrence and the associated risks are poorly understood.
In this project you will use a coupled Earth system model to investigate intensity and frequency of air quality standard violations in Europe under different future emission scenarios from the IPCC AR5 RCP projections. Using data from the 2003 European heatwave, you will investigate the processes controlling high ozone and PM loadings in Europe during these types of event. You will then characterise the mechanisms controlling severe episodes of reduced air quality and regions most at risk on time horizons from near future (~2030) through to far future (2100). Of particular interest is the interaction between natural processes (such as emissions from and deposition to vegetation) and anthropogenic emission and land-use changes. Using existing exposure metrics for human health, you will quantify health risks from your projections of future ozone and PM in different regions of Europe under the different scenarios.
References
- Fischer, P.H, B. Brunekreef and E. Lebret, (2004), Air pollution related deaths during the 2003 heat wave in the Netherlands, Atmos. Environ., 38, 1083-1085.Guenther, A., et al., (1995), A global model of natural volatile organic compound emissions, Journal of Geophysical Research, 100, pp. 8873–8892.
- Mickley, L. J., D. J. Jacob, B. D. Field, and D. Rind (2004), Effects of future climate change on regional air pollution episodes in the United States, Geophys. Res. Lett., 31, L24103, doi:10.1029/2004GL021216
- Spracklen, et al., (2009), Impacts of climate change from 2000 to 2050 on wildfire activity and carbonaceous aerosol concentrations in the western United States, J. Geophys. Res., 114, D20301, doi:10.1029/2008JD010966.
- Stedman, J.R., (2004), The predicted number of air pollution related deaths in the UK during the August 2003 heat wave. Atmos Environ., 38, 1087-1090.