|A Bayesian Model for Quantifying the Change in Mortality Associated with Future Ozone Exposures Under Climate Change|
Stacey Alexeeff, NSF Postdoctoral Fellow
National Center for Atmospheric Research
Monday, November 3rd 2014
Climate change is expected to have many impacts on the environment, including changes in ozone concentrations at the surface level. A key public health concern is the potential increase in ozone-related summertime mortality if surface ozone concentrations rise in response to climate change. Previous health impact studies have not incorporated the variability of ozone into their prediction models. We propose a Bayesian posterior analysis and Monte Carlo estimation method for quantifying health effects of future ozone.
The key features of our methodology are (i) the propagation of uncertainty in both the health effect and the ozone projections and (ii) use of the empirical distribution of the daily ozone projections to account for their variation. The use of interpolation to improve the accuracy of averaging over irregular shaped regions helps to derive average exposure for the regions where mortality and demographic information is reported. We also derive an analytic expression for the integral with respect to the mortality parameter, which is useful to reduce the Monte Carlo computational burden associated with this parameter. Using our proposed approach, we quantify the expected change in ozone-related summertime mortality in the contiguous United States between 2000 and 2050 under a changing climate. We also illustrate the results when using a common technique in previous work that averages ozone to reduce the size of the data, and contrast these findings with our own. g