3.3.8. Layalloc

3.3.8.1. Description
3.3.8.2. Processing Order
3.3.8.3. Files and Environment Variables

3.3.8.1. Description

The Layalloc program calculates 3-D emissions from a 2-D pre-gridded emissions file. Layalloc is used to reallocate single layer 2-D surface layer emissions into multiple model layers. This approach is useful for processing pre-gridded or industrial area source inventories that do not contain stack information for plume rise treatment but represent elevated sources.

Layalloc reads in a gridded 2-D pre-gridded emissions file (either output from the Smkmerge program or from a pregridded global emission inventory (EDGAR/RCP/HTAP)) and redistributes the emissions into multiple model layers based on a user-defined vertical profile. The vertical profiles that are input to Layalloc consist of a layer bottom height, layer top height, and the fraction of emissions to allocate to the layer. SMOKE willl interpolate from the layer heights (in meters) to the model layers (in sigma-pressure). This approach assumes that the vertical factors are uniformly applied over all horizontal grid cells. The resulting hourly, gridded, speciated 3-D emissions data are output to a new I/O API file with the same temporal resolution and the same model species as the original 2-D emissions file.

3.3.8.2. Processing Order

This optional program can be run after Smkmerge and before either Mrggrid (if it is being used to merge several Smkmerge output files together) or the AQM of interest.

3.3.8.3. Files and Environment Variables

3.3.8.3.1. Input Files
File Name Format Description
INFILE I/O API NetCDF 2-D hourly, gridded, speciated inputs from Smkmerge. INFILE should be set to logical file name AGTS_[L|S], BGTS_[L|S], MGTS_[L|S], PGTS_[L|S], or EGTS_[L|S], which are the output files from Smkmerge.
MET_CRO_3D I/O API NetCDF Meteorology file contains a variable “ZF” which is full-layer height above ground (m)
LAYER_FRACTION ASCII

File that lists the layer top and bottom heights in meter(s) along with a percentage factor. For example, the following LAYER_FRACTION file sample would distribute 2-D emissions into multiple model layers based upon five user-defined layers.

No., Bottom Ht(m), Top Ht(m), Fraction
1,         0,        100,        0.60
2,       100,        200,        0.20
3,       200,        400,        0.10
4,       400,        600,        0.07
5,       600,       1000,        0.03
3.3.8.3.2. Input Environment Variables

None

3.3.8.3.3. Output Files
File Name Format Description
LOGFILE ASCII Log generated from executing Layalloc
OUTFILE I/O API NetCDF 3-D hourly, gridded, speciated emissions, adjusted based on LAYER_FRACTION.