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Gas Solver Problem

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New member
Hi all,

I have been having some issues trying to run an experiment. The error has been generating a *** gasodesolver_rodas failure *** error. I have attempted to troubleshoot it but no headway.

Please see the namelist file and rsl.error file.

Thank you


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  • rsl.error2.txt
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This is likely related to your time step choices - you have a meteorological time step of 5 minutes, and a chemistry timestep of 1.5 minutes. My suggestion would be to set chem_dt = 0 and/or reduce the meteorological time step to < chem time_step.

Hi Jordan,

Thank you for your reply. Does it make sense if the chem time step is zero and the meteorological time step is left as same, or you advise that I set both as same.

time_step = 100
chem_dt = 100
Setting the chem_dt = 0 just means to run chemistry at each time step, so yes, pick a shorter met time step and set chem_dt = 0.

Thank you jordan... The server was down for some days and also add some other cfl errors. However, I think it's fine now... I just set chem_dt = 0 and phot_dt = 0 so it used the met time step.

No problem. Note that calling the photolysis driver and related optical routines at each time step will increase the integration time. You can generally set this to much lower than the chemistry time step (your original choice of 30 would probably be sufficient, but you may want to run some sensitivity experiments).