[MITgcm-support] how to control obcs balance flow ?

[Martin Losch]

All you need to do is to specify the appropriate “period”, i.e. the interval between forcing data sets, and the date and time of the first record in your data set. For monthly it would be 30 days (for a model calendar with 360 days), so,e.g. hfluxperiod = 2592000., etc., and if you consider your values as monthly means centered in the model of the month and your first year is 2007, you’d have hfluxstartdata1 = 20071601, and hfluxstartdate2=000000 (=default, for midnight)
The exf-package will then do the (linear) interpolation for you.

M.

On Apr 30, 2014, at 4:15 AM, 李志远 <oceanlizy at 163.com> wrote:

> From: LIZHI  <oceanlizy at 163.com
> >
> To: MITgcm Support <
> mitgcm-support at mitgcm.org
> >
> Subject: Re: [MITgcm-support] how to control obcs balance flow ?
> 
> Thank you Matt for your quick reply . 
>       when I use monthly forcing in the exf , how to use  interpolate with time  , such  as interpolate monthly fields into daily  . It should be defined in the exf_options.h  ?
> 
> THANK YOU !
> >Subject: Re: [MITgcm-support] how to control obcs balance flow ?
> >Message-ID: <34AD18CB-1240-4517-A074-86F84EE61416 at ucsd.edu>
> >Content-Type: text/plain; charset="utf-8"
> >
> >Hello
> >
> >Yes -- due to intrinsic periodicity and the fact that W is on the west side of the cell for OBCS you should use
> >hFacW(2,:,:) on the west wall and hFacS(:,2,:) on the south wall
> >
> >You can use 
> > hFacW(end,:,:) on the east wall and hFacS(:,end,:) on the north wall. 
> >
> >This allows you to control inflow.
> >
> >It is safer to make flat bathy in the normal direction for at least the two cells at the boundary. If you use obcs_sponge its better to have flat boundary in the normal direction over the whole sponge so as to not drive a bottom divergence. If you are sponging to a non-zero tangential velocity you should be careful and check how large your W is as the divergence of this velocity will not be balanced by a normal flow divergence.
> 
> >It is fine to choose difference forcing periods for different input fields.
> 
> >Matt
> 
> 
> 
> 
> 
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