Find majority county coverage in model grid cells

Question

How do I figure out which grid cells (x, y) contain any part of the Chicago ozone nonattainment area?

Approach

Use a GIS to find the counties that intersect the model grid cells.

Details

1. Create a shapefile of the 12US2 modeling grid (396x246)

Use the [Spatial Allocator] raster tools to create the shapefile. See generateGridShapefile.csh script as an example.

  setenv GRID_PROJ "+proj=lcc +a=6370000.0 +b=6370000.0 +lat_1=33 +lat_2=45 +lat_0=40 +lon_0=-97"

  setenv GRID_ROWS 299
  setenv GRID_COLUMNS 459

  setenv GRID_XMIN  -2556000.0
  setenv GRID_YMIN  -1728000.0

  setenv GRID_XCELLSIZE 12000
  setenv GRID_YCELLSIZE 12000
 
  setenv GRID_SHAPEFILE_NAME ../output/conus_cmaq12km.shp