Re: WRF: Relative vorticity and Divergence

In order to use the suggested functions, you would have to interpolate
the curvilinear WRF coordinates XLAT/XLONG to a regular [rectilinear]
grid using:

    http://www.ncl.ucar.edu/Document/Functions/Built-in/rcm2rgrid.shtml
or
 
http://www.ncl.ucar.edu/Document/Functions/Contribute/rcm2rgrid_Wrap.shtml

Then use the uv2dv_cfd & uv2vr_cfd functions.

Finallay interpolate back to the original WRF coordinates

    http://www.ncl.ucar.edu/Document/Functions/Built-in/rgrid2rcm.shtml

or

 
http://www.ncl.ucar.edu/Document/Functions/Contributed/rgrid2rcm_Wrap.shtml

====
Note:
If the purpose is for deriving vorticity/divergence is "visual",
then the above approach is probably adequate for both quantities.
However, if the derived quantities are going to be used as the basis
for further derivations, they should be used with extreme caution
[in particular, divergence].

On 04/18/2010 11:44 AM, Mateus Teixeira wrote:
> Dear Sahidul,
>
> You can calculate relative vorticity and divergence with uv2vr_cfd and
> uv2dv_cfd, respectively. Please take a look at
>
>
> uv2dv_cfd -> for divergence
> http://www.ncl.ucar.edu/Document/Functions/Built-in/uv2dv_cfd.shtml
>
> uv2vr_cfd -> for vorticity
> http://www.ncl.ucar.edu/Document/Functions/Built-in/uv2vr_cfd.shtml
>
> Examples for Vorticity
> http://www.ncl.ucar.edu/Applications/vort.shtml
>
>
> I hope that it helps you.
>
> Best regards,
>
> Mateus
>
>
> 2010/4/18 Sahidul <sahidul@gmail.com <mailto:sahidul@gmail.com>>
>
> NCL Users,
>
> We have WRF forecast files, saved in 1 hour interval having total 88
> files. We want contour plot for "Relative Vorticity" and
> "Divergence" every hour.
>
> Is there any function or Script for calculating "Relative Vorticity"
> and "Divergence" ?
>
> Thanking you,
>
> _______________________________________________
> ncl-talk mailing list
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>
>
>
>
> --
> Mateus da Silva Teixeira
> Meteorologista
> Instituto de Pesquisas Meteorológicas - IPMet
> Universidade Estadual Paulista - UNESP
> Av. Luis Edmundo Carrijo Coube, 14-01 - Cx. Postal 281 - CEP 17033-360
> Bauru - SP - Brasil
> Fone: +55 14 3103-6030 / fax: 3203-3649
>
> Registered Linux User #466740 (http://counter.li.org/)
>
>
>
> _______________________________________________
> ncl-talk mailing list
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk

-- 
======================================================
Dennis J. Shea                  tel: 303-497-1361    |
P.O. Box 3000                   fax: 303-497-1333    |
Climate Analysis Section                             |
Climate & Global Dynamics Div.                       |
National Center for Atmospheric Research             |
Boulder, CO  80307                                   |
USA                        email: shea 'at' ucar.edu |
======================================================
_______________________________________________
ncl-talk mailing list
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk