4.15. Smkmerge

4.15.1. Description
4.15.2. Processing Order
4.15.3. Files and Environment Variables

4.15.1. Description

Processing categories: area, biogenic, mobile, point

The Smkmerge program combines the matrices produced by the other SMOKE programs to produce the emissions files for input to the AQM. The Smkmerge program may be run on any combination of source types and may incorporate temporal, speciation, projection, and spatial processing.

If Smkmerge is run to produce the input files to the AQM, all the other SMOKE programs must already have been run. However, you can also run Smkmerge to produce specialized reports. In that instance, only the required subset of SMOKE programs must have been run prior to Smkmerge.

Smkmerge can be used to create 2-D or 3-D gridded, hourly, speciated files. It also outputs the hourly emissions file for PinG sources needed by CMAQ. Finally, it outputs an ASCII elevated point sources file, suitable for postprocessing with the Ptsrce program of EPS2.0/EPS2.5. If PinG sources have been selected and an ASCII elevated sources file is output, then SMOKE will set the stack diameters to negative values for the PinG sources.

4.15.1.1. By-day processing

Smkmerge can use a by-day processing approach, to read in one-day hourly files for each day of the week. When the MRG_BYDAY environment variable is set to A, M, P, or any combination of those letters, Smkmerge reads a different logical file name for each day of the week for the hourly emission input files for the indicated sources.

For example, if the MRG_SOURCE environment variable is set to AMBP, Smkmerge will expect the following hourly input files: ATMP, BGTS_[S|L], MTMP, and PTMP, for area, biogenic, mobile, and point source types respectively. If, in addition, MRG_BYDAY is set to “A”, then the hourly input files expected by Smkmerge for area sources would be the ATMP_{day} files. The files for the other source types would remain the same.

The MRG_BYDAY option is useful for implementing a Monday-weekday-Saturday-Sunday (MWSS) approach to save processing time for long episodes. This approach is applicable when weekly temporal profiles used by an inventory do not have variation between the five weekdays. In the MWSS approach, Monday is processed separately, because time zone differences across a large domain cause some Sunday emissions for some time zones to be in the Monday file. Additional environment variables other than the defaults in the Assigns file need to be set when this option is applied. Smkmerge will prompt for a different file for each day of the week, but the logical file names for Tuesday through Friday can be defined as the same file when implementing the MWSS approach.