Plume in Grid (PinG) is a subgrid-scale treatment of the plumes from large point emissions sources. PinG is a technique to resolve the chemistry and dynamics of the plumes from selected point sources at a finer spatial resolution than the grid being modeled. Additional information about the PinG formulation in CMAQ is available in Byun and Ching (1999) and Byun and Schere (2006). The Plume Dynamics Model (PDM) is the PinG preprocessor in CMAQ that prepares special emissions files with information about sources selected for PinG treatment for input to the CCTM. The PDM simulates plume rise, horizontal and vertical plume growth, and transport of each plume section during the subgrid scale phase of the plume cycle. The PDM outputs an active plume file that is input to the CCTM along with the major elevated point source emissions (MEPSE) file from an emissions processing system to simulate selected point sources with the PinG treatment. Figure 2-7 is a schematic that relates PDM to other components in the CMAQ modeling system.
Figure 2.7