A REDUCED-ORDER PHOTOCHEMICAL AIR QUALITY MODEL

Abstract

We report on reduced-order photo-chemical model (TAPOM-Lite) designed for calculating ozone levels for varying urban scenarios and calibrated for the city of Geneva, Switzerland. The TAPOM-Lite model is an atmospheric-environmental model designed to be incorporated into a larger energy–economy–environment (E3) model and run in an optimization framework. The motivation for the TAPOM-Lite model was the design of a fast ozone calculator needed for the CPU-intensive optimization environment where many iterations are potentially required before a best solution is found. Three principal advances in this model are (1) a simplified chemical scheme for O3 production, (2) linearization of the O3 production function needed for the overseeing linear optimization program, and (3) the extraction of gradient (sensitivity) information calculated from the O3 production function which in turn is needed as “directional” information in the optimization method. Results show that the TAPOM-Lite model is consistent with the full-scale TAPOM model throughout the optimization/iteration process. The TAPOM-Lite model provides a first coupled E3 program for optimization and also provides a framework for global application such as the linking of global indicators (e.g., mean temperatures) and world energy consumption.