[MITgcm-support] Bulk Force and SSS restoring

[Amato Evan]

Hi Martin,

Thanks a lot for chiming in here!

> in data.cal you can specify the 'model calendar' (see  
> global_with_exf for an example), so that should not stop you from  
> use exf instead of bulk_force. Although my experience with  
> bulk_force is very limited, the exf does have quite a few options,  
> and I think it should do what you need.
I would certainly much rather use EXF. global_with_exf has  
"TheCalendar='gregorian'". I did incorporate cal and exf into my  
current model setup, but I could not get the model to run if I had  
"TheCalendar='model'" (it did work w/gregorian though). And then I saw  
something on the mailing list where someone said that with EXF you  
have to use the gregorian calendar. Then I stopped playing with EXF  
since I don't want to deal w/leap years!

> Did you have a look at global_ocean.cs32x15/input.thsice/ for an  
> example use of bulk_force?
I did, I can get BULK_FORCE going in my model setup, I'm just trying  
to determine if I can use it w/o the model calculating freshwater  
fluxes from a rain or runoff file (only SSS restoring), which I  
couldn't deduce from the code/documentation. Not such a huge thing if  
not I suppose. I'm just trying to save myself some time.

Sincerely,
Amato



>
> Martin
> On Feb 17, 2010, at 3:58 PM, Amato Evan wrote:
>
>> Hi Stefano!
>>
>> I was hoping to use the model calendar (just b/c it's more  
>> straightforward) and as far as I can tell, if one uses EXF then  
>> calendar has to be set to "Gregorian". Is this right?
>>
>> I should say that another reason for only restoring to SSS is that  
>> this is how I have spun up the model, so I'd like to stay  
>> consistent on this front as well.
>>
>> Thanks for your time, I really appreciate it!
>>
>> Sincerely,
>> Amato
>>
>> On Feb 17, 2010, at 4:37 AM, Stefano Querin wrote:
>>
>>> Hi Amato,
>>>
>>> just a few ideas...
>>>
>>> Have you ever tried to use the EXF package for your simulations? It
>>> should be more complete and flexible than the BULK_FORCE package.  
>>> You
>>> can also restore SSS to prescribed values with it.
>>>
>>> I don't think that the computation of freshwater fluxes using runoff
>>> and precipitation input files makes the model run that slow... (but
>>> I'm just relying on my experience, I never made any test regarding
>>> this). On the contrary, if you meant that the creation and handling
>>> (offline) of runoff and precip files is somehow cumbersome and slow,
>>> then SSS restoring should be a more desirable choice.
>>>
>>> Anyway, the EXF package has many available options.
>>>
>>> Hope this helps...
>>>
>>> Cheers!
>>>
>>> S.
>>>
>>>
>>>
>>> On 16 Feb 2010, at 19:50:23, Amato Evan wrote:
>>>
>>>> Hello Everyone,
>>>>
>>>> I am trying to estimate the effect of surface forcing by volcanic-
>>>> aerosols on tropical SST. To do this I have a 1x1 degree model  
>>>> setup
>>>> w/23 vertical levels. After spining up the model for 130 years  
>>>> using
>>>> NCEP and WOA data (and SSS restoring), I would like to "turn-on"  
>>>> the
>>>> BULK_FORCE package in order to change downward lw & sw fluxes in
>>>> accordance with volcanic aerosol surface forcing (something I
>>>> calculate offline w/satellite obs. and an RT model).
>>>>
>>>> I am giving the BULK_FORCE pkg wind stress values (calcWindStress
>>>> = .FALSE.), but I would like to run w/surface salinity restoring,
>>>> and not have the model calculate freshwater fluxes using runoff and
>>>> precip input files. My motivation is just to make the model runs
>>>> complete more quickly. What I can't determine from the  
>>>> documentation
>>>> and source code is if I leave:
>>>>
>>>> RainFile= ' ',
>>>> RunoffFile= ' ',
>>>> EmPFile= ' ',
>>>>
>>>> in data.blk, will bulk_force just restore to surface salinity on  
>>>> the
>>>> time scales I define in "data"? If anyone has experience with this,
>>>> I would really appreciate input. Also, the contents of build/,
>>>> code/, and input/ for my setup can be found here:
>>>>
>>>> http://trane.evsc.virginia.edu/mitgcm/
>>>>
>>>> If anyone is so inclined to look them over.
>>>>
>>>> Thanks!
>>>>
>>>> Sincerely,
>>>> Amato

---
Amato Evan
Asst. Professor
Dept. of Environmental Sciences
University of Virginia
434.243.7711
aevan at virginia.edu
http://trane.evsc.virginia.edu