Variability and Uncertainty in Ambient Air Quality

Quantification of Variability and Uncertainty in Ambient Air Quality

This research extends the probabilistic and uncertainty analysis methodologies to the field of ambient air quality modeling. The work focused on quantifying how uncertainties in key model inputs, such as hourly utility nitrogen oxide (NOx) emissions, propagate through complex photochemical grid models to affect predictions of ozone concentrations. By analyzing the uncertainties in these predictions, this research provided policymakers with a more reliable understanding of the effectiveness of air quality management strategies and the sensitivity of air quality outcomes to different emission sources, making it a methodological contribution to air quality science.

Illustrative papers (selected examples): 

Hanna, S.R., Z. Lu, H.C. Frey, N. Wheeler, J. Vukovich, S. Arunachalam, M. Fernau, and D.A. Hansen, “Uncertainties in Predicted Ozone Concentrations due to Input Uncertainties for the UAM-V Photochemical Grid Model Applied to the July 1995 OTAG Domain,” Atmospheric Environment, 35(5):891-903 (2001).

Abdel-Aziz, A., and H.C. Frey, “Propagation of Uncertainty in Hourly Utility NO_x Emissions Through a Photochemical Grid Air Quality Model:  A Case Study for the Charlotte, NC Modeling Domain,” Environmental Science and Technology, 38(7):2153-2160 (2004).