search

metno / emep-ctm

Open Source EMEP/MSC-W model
GNU General Public License v3.0
30 stars 20 forks source link

Turn off dry deposition for testing purposes? #101

Closed rubenww closed 1 year ago

rubenww commented 2 years ago

Hello, I'm looking for a way to completely turn off dry deposition for a specific component (e.g. NH3) for testing purposes. I'm using EMEP v4.36. I didn't find any parameter in the USES list in Config_module.f90 that could be used to do this.

I've looked in DryDep_mod.f90 and it seems there is no option in there either. Would it be enough to set

cfac(nadv,i,j) = 1.0   
DepLoss(nadv) = 0.0

Inside the DDEPLOOP and then in the DCMPLOOP (starting on line 796) for the case that icmp = idcmpNH3 or do I need to change the deposition velocities as well?

Any help/insights would be greatly appreciated. If useful, I can turn it into an option and create a pull request. Thanks!

mifads commented 2 years ago

Hi! I think that your suggestion should be fine, and not cause any problems as long as the change is inside the DCMPLOOP. This makes the change applicable to just that one species (with nadv), and not to anything else with the same "icmp". My only suggestion here would be to use the simpler test:

if ( ntot == NH3) then
   cfac(nadv,i,j) = 1.0   
   DepLoss(nadv) = 0.0
end if

since this is more easily extended to other gases if this is of interest.

rubenww commented 2 years ago

Thanks a lot! I'll try it and report back if it works. Would you be interested in a PR, possibly using some option like USES%NO_DRYDEP = 'NH3'?

mifads commented 2 years ago

As soon as we have sorted out some technical issues we will be releasing a new open-source version of the model. So, no pull requests before then please, but after that would be fine! I'd suggest using DEBUG%NO_DRYDEP though, since this is really a special type of sensitivity test, not a "normal-usage" model option. Thanks!

rubenww commented 2 years ago

I have implemented the option here: https://github.com/rubenww/emep-ctm/tree/my_f_no_drydep I have also performed some test runs with it, everything works as expected. I'll create a PR once the new version becomes available.

mifads commented 1 year ago

Nothing happened here, and a new emep-ct is also on the way in the next week or so (I hope). I'll close for now. Just re-open if interested.