I plan to run CMAQ in a high spatial resolution (e.g., 1 km resolution). I was wondering if there are any specific flags that I need to set in the CMAQ run script that is required for such a high spatial resolution simulation.
I don’t believe there are any specific flags that you need to run higher resolution grids using CMAQ. You will need inputs from meteorology, emissions, boundary conditions, and initial conditions. Boundary conditions conditions are typically obtained from nesting down from a coarser domain.
An example for CMAQ is to obtain boundary conditions from the Hemispheric CMAQ run, then run 12km for the CONUS US then 4km for a region then 1.33 km (dividing each grid resolution by a factor of 3) for a city.
An alternative to running CMAQ for the coarser domains is to obtain the data from the CMAS Data Warehouse.
Data for the 2018 12km CONUS domain can be obtained from the Google Drive
AWS Open Data Registry: CMAS Data Warehouse - Registry of Open Data on AWS