AERMOD became the US EPA-required regulatory short-range dispersion model in November 2005, replacing ISCST3, which was the recommended model for the previous two decades. The South Coast Air Quality Management District (SCAQMD) needed a standard set of meteorological inputs to perform regulatory AERMOD model runs.
EnviroComp was asked to develop these meteorological input files to fill the same role for AERMOD as those currently maintained by AQMD for use with ISCST3, to be downloadable by modelers for regulatory applications of AERMOD within the AQMD.
To develop the input files for AERMOD we first surveyed available meteorological station data (Figure 1) throughout the Southern California area and incorporated these data into "pre-processed" input files for AERMET, one for each of the AQMD sub-areas within the district. We then ran AERMET for each sub-area, which created the *.sfc (surface) and *.pfl (profile) AERMOD input files for each district sub-area. A flowchart of the methodology is presented in Figure 2.