[MITgcm-support] river runoff

[Andrea Cimatoribus]

Certainly not the most expert around here, but I have been dealing with 
this lately, so I can try an answer.

The neatest way to do it is with obcs package, that is, the open 
boundary package. In data.obcs you can define the (vertical) grid faces 
through which you want to apply the discharge (see manual). Using the 
correct grid metric, you can set the discharge velocity to match the 
total volume discharge (and you can easily check if you are doing it 
right using the diagnostic output). The simplest way to impose a 
time-variable discharge and temperature is via the exf package, in a new 
namelist which is provided by the OBCS package, something along these lines:
  &EXF_NML_OBCS
# OBCS prescribe
  obcsEstartdate1   = 20080101,
  obcsEstartdate2   = 010000,
  obcsEperiod       = 3600.,
  obcsWstartdate1   = 20080101,
  obcsWstartdate2   = 010000,
  obcsWperiod       = 3600.,
  &
As far as I understand, the temperature of the discharge must span 
exactly the same time interval and have the same periodicity as the 
velocity.
The file names containing the data are defined in the data.obcs (again, 
see manual).

Hope this helps, best,

Andrea Cimatoribus
postdoctoral researcher
EPFL ENAC IIE ECOL
https://people.epfl.ch/andrea.cimatoribus

On 09/11/16 03:26, 钱钰坤 wrote:
> Hi
>
> I am using mitgcm to simulate SST variation in coastal area with large
> runoff. Does anyone tell me how to set up the river? How mitgcm deal
> with river mouth?
>
> I've known that the runoff should be added to the freshwater flux EmPmR,
> but how to represent the effect of a river by gridded runoff data is not
> clear to me (should the river grid point be contacted with ocean
> interior or boundary?).
>
> It seems that the test cases in mitgcm do not provide enough river
> information.
>
> I'd appreciate any help.
>
>
> ------------------
> Best regards
>
> Yu-Kun Qian (钱钰坤)
> Center for Monsoon and Environment Research
> Department of Atmospheric Sciences
> School of Environmental Science and Engineering
> Sun Yat-sen University
> No. 135 Xingang West Road, Haizhu District
> Guangzhou, 510275, P.R. China
> Tel; 020-84115227
> Email: qianyk at mail3.sysu.edu.cn <mailto:qianyk at mail2.sysu.edu.cn>
>
>
>
>
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