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How to re-initialized a simulation?


Dear all,
I have a question about the WRF-Chem setup. I recently read a paper that stated " All the simulations are initialized at 15 UTC 24 April 2016, and the first six-day results are not used for analysis. Note that the simulations are re-initialized at 15 UTC on 23 May 2016 to better capture the meteorology during 24–26 May, especially for clouds. "
(check the attached screenshot)
Now I wonder how it would be possible to re-initialize a simulation at a specific time, please?

Would you please help me in this regard?
Thanks in advance.


  • Screen Shot 1402-07-27 at 15.40.33.png
    Screen Shot 1402-07-27 at 15.40.33.png
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Dear seti,
Without further information from the rest of the article (or the supplement), I assume the authors mean that they have started a new WRF-Chem simulation on 15 UTC, 23 May (that uses the met_em files from WPS) and so the meteorology is re-initialized with the input data at that time step.
Usually this simulation is run for a couple of hours to spin-up, after which a restart file is written (however, the spin-up time is not specified here). Then a restart simulation is started from this timestep, while all chemical fields from the previous run (those that started in April) are copied into the corresponding fields of the restart file. As such, the meteorology is split in two runs, while the chemistry runs continuously. I have experience with doing such re-initialization using the passive tracer option (17), however I am not sure if the method is the same for other options.
To be sure if that is what the authors did, I would suggest to contact the authors of this publication directly.
Hope this helps,
Kind regards
Dear callewaerts,
Thanks for your explanations. I attached the article. would you please have a look at the paper and make sure of their method? The method is explained on page 2.

Kind regards,


  • 1-s2.0-S1352231022001388-main.pdf
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It is not entirely clear from the paragraph in the article. If you want more detail on how exactly they implemented it, I would suggest to contact the authors.