Biochemistry Output

[osfp19782000@yahoo_gr]

Hi guys

I would like to have biochemistry to CLM3.5 first run. How can I get biochemistry output from CLM3.5 such as CO, CO2 or NOx?

Thanks

 

[slevis]

Not sure if such output is available in clm3.5. In any case, to run with the CN model (active carbon and nitrogen), you need to set bgc=cn in your jobscript. Unfortunately CN is not documented and, therefore, not supported, yet. It will be documented in the next release (clm4.0), expected about a year from now.

You may be able to get CO output by running the clm3.5 BVOC module (biogenic volatile organic compounds). This module has not been tested in a while, so I will not guarantee that it works.

Good luck (kalh tuxh)
Sam Levis

 

[osfp19782000@yahoo_gr]

Thanks very much Sum, I appreciate your interesting and I want to ask you this. How can I switch on CN module by the script (I mean the flags...)

Thanks

Nikitas Papantoniou

 

[slevis]

In your jobscript you can set any of the following that you want:
set bgc = cn
set voc = on
set dust = on
Again, I'm not sure whether voc and dust have been tested recently. And CN works but requires a long spin up and there's no available documentation, yet, for that. Here's a summary from an email that I sent someone else (that's the extent of the help I can provide at this time):

Sam Levis wrote:

The problem with providing spun up data is not that the files may come from my own research, but that each user would need a different file depending on the spatial resolution that they were using. Clm3.5 includes a tool for mapping initial files from one resolution to another (interpinic), but I don't think that this tool works for CN. When we release clm4 (summer '09), we will probably include spun up data for CN and a version of interpinic that works for CN. For now you have to spin up the model yourself.

Sounds as though the model works for you now. Restart and initial files contain the same list of variables, so initial files are unnecessary. You can point to a restart file to do a startup, branch, or restart simulation, and all three simulations should work. As you said, atmospheric data comes from the Qian et al. data. The date on the history files depends on the start date in your namelist.

Pls read the clm documentation (available from the clm3.5 distribution page, http://www.cgd.ucar.edu/tss/clm/distribution/clm3.5/index.html). Although most of it was written for clm3.0, you will find it very helpful in answering your questions. My purpose is to help you out when you run out of ideas of how to proceed. For now, maybe while CN spins up, you should read the documentation.

Good luck with your project.

Sam

[...]

> Samuel Levis wrote:
>>
>> We do not provide spun up initial conditions for the CN model. So in the clm namelist you need to set finidat=' ' (ie, a blank string). When you do this, the model will start with initial conditions that are hardwired in the clm code, and the CN model will need about 700 years of spinup. Here is the procedure to spin up CN:
>>
>> In all these steps, CN is defined.
>> 1) define AD_SPINUP and run for about 600 yrs
>> 2) undefine AD_SPINUP, define EXIT_SPINUP, and run for 1 year
>> 3) undefine EXIT_SPINUP and run for a minimum of 50 yrs. Continue step 3 until CN looks spun up.
>>
>> Sam