Does CMAQ use the emissions of 25th hour?

Hi all,
As we know that CMAQ area source emission file generally has 25 hour timestep (from 0AM to 0AM of the next day) and there are 24 hours in ACONC and 25 hours in CONC files, I wonder whether the emission of 0 AM of the next day (which is the 25th hour in emission file) is used in CMAQ simulations?
Any clarifications would be appreciated!


Hi Ryan,

Yes, all 25 hours are used from the emission files. The rates provided by the emission files are instantaneous rates and they are interpolated to each model time step as the simulation proceeds. So the 25th hour of the file is used to interpolate emissions from 23:00 on Day 1 to 00:00 on Day 2.

Best regards,

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Hi Ben,
Thanks for the clarification which makes it clear.