How CCTM interpolate meteorology data for the run?

Hi
I have a question about running the CMAQ model. We have WRF output in 1-hour time step. How CCTM interpolate MCIP output to run the model? because the max sync time step is 300 sec.
Thank you

I/O API routine INTERP3: see https://www.cmascenter.org/ioapi/documentation/all_versions/html/INTERP3.html

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Hi Carlie
Thank you for your reply. Suppose we have meteorology for 1 and 2 o’clock. Could you guide me on how to interpolate data for 1:05, 1:10, 1:15, 1:20, …, 1:45, and 1:55 from data of 1 and 2 o’clock?
I saw the link you sent, but I couldn’t solve my problem. Could you help me, please?
Thank you

INTERP3 maintains double buffer arrays for this variable (let’s call it V) and (for this example) times 1:00 and 2:00 – V1 at 1:00 and V2 at 2:00, respectively. Then at 1:05, let
P = (2:00-1:05)(2:00-1:00) = 55.0/60.0
and
Q = 5.0/60.0
be the linear-interpolating-fraction coefficients to interpolate from 1:00 to 2:00 (note that P+Q=1). To get V at 1:05, do the array-arithmetic P*V1 + Q*V2.

And similarly, at 1:10, P = 50.0/60.0 and Q = 10.0/60.0. etc.

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