Performance of Kriging and EWPM for Relative Air Pollution Exposure Risk Assessment

This study investigates the effectiveness of the Kriging interpolation model and the Emission Weighted Proximity Model (EWPM) in assessing relative exposure risk of air pollution using results from the American Meteorological Society/EPA Regulatory Model (AERMOD) as benchmarks. We used simulated exposure risk to SO2 in the Dallas area in Texas in this evaluation. Results suggest that the relative exposure risks to SO2 at different locations in the study area as estimated by EWMP are closer to estimated risks from AERMOD when compared with the results calculated by Kriging. In addition, study results also indicate that the relative exposure risks calculated by Kriging are similar to those from AERMOD when the density of emission sources in the area in question is high. It is therefore concluded that relative exposure risks determined by both the Kriging interpolation method and the EWPM are acceptable when it is not possible to use AERMOD. In situations when the density of emission sources is low in the study area, EWPM is a better choice than Kriging.