forcing routines in pop2

[bitz]

I noticed a bunch of routines in the pop2 directory for forcing the model with freshwater and other parameters. The manual says that they are only meant to be used for uncoupled integrations. However, as I have delved into the code, there does not appear to be anything preventing the code from working in coupled mode. Has anyone used these routines in coupled mode? It looks like we just turn on some namelist variables and make a forcing input file. Is this right? 
I'd also be grateful to see an example of a forcing file, so I can use it as a template for my own input file. Any type of forcing would do. I realize that there are many options that will require the input to be custom made, but it would still be helpful to see a sample. Thanks!

 

[njn01]

There are many forcing options available in the CESM version of POP2, as you have discovered from reading the manual and examining the code and namelist options.The interactions between the various namelist variables and settings that control the forcing are very complex, and we recommend against setting them "by hand." It is for this reason that the behind-the-sceens CESM scripts automatically set the forcing options for you, based upon standard CESM compsets.
You are correct that a developer could modify the forcing options, variables, code, and files in order to create a customized experiment, but without a deep understanding of the CESM POP2 forcing code and its interactions with the entire model, you may end up with something that appears to be working, but is incorrect.In the past, there was a CESM ocean science liaison dedicated to working with our user community when questions like your arose. Unfortunately, this position has been eliminated, with the result that complicated issues such as yours cannot be resolved as promptly and completely as we would want.

 

[njn01]

If you are interested in modifying the freshwater forcing routines for a "hosing" experiment, you may find some additional information in the recently updated CESM1.2 POP2 FAQhttp://www.cesm.ucar.edu/models/cesm1.2/pop2/doc/faq/

 

[bitz]

Thanks for the information! I'll try out the suggestion that was added to the FAQ. I also can answer my own second question. There are examples of input files in the inputdata directory, such as inputdata/ocn/pop/gx1v5/forcing/

 

[matthew_thomas@yale_edu]

Dear bitzI recently came across this thread, and was wondering if you eventually got the freshwater hosing to work in CESM according to the method outlined in the FAQ's? If you did, would you mind informing me of your approach?I also want to apply hosing, but by reading in and adding on an additional surface freshwater flux that I have saved on file. I am not sure, however, of the best way to geographically split up the fluxes among the various different processors. I outlined the problem in more detail here: https://bb.cgd.ucar.edu/freshwater-hosingI would be very happy to hear about the method you eventually applied, should you be able to recall/access what you did. Thanks very much and all the best,Matthew 

 

[bitz]

Yes I did manage to get it to work, and I'm happy to point you to my code. I wrote a README, but it is not the most impressive documentation (or coding for that matter). If you still want it, feel free to email me. I'm easy to find on the internet. My user name is my last name. Also you may like to see our paper on hosing the Southern Ocean that just came out at http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0501.1Cecilia