how to plot the wind following two-dimensional terrain in Grads

[Charles Seman]

Dear Dipak,

Here are copies of parts of email exchanges to the GrADS Listserv from
Wesley Ebisuzaki and Mary Jo Nath which may be of some help?

from Wesley Ebisuzaki:
---
Subject:
Re: vertical acorss section
From:
Wesley Ebisuzaki <Wesley.Ebisuzaki at NOAA.GOV>
Date:
Tue, 24 Aug 2004 14:57:46 -0400
To:
GRADSUSR at LIST.CINECA.IT

Found this .gs file in a dusty directory.  Need to change
the ccols for white/black orography.

-------------------------- orog.gs ------------------------
*
* Display orography on vertical profile
*
* pressfc = surface pressure in Pa
* lev is assumed to be in hPa
*
* display is assumed to be in "shaded" and vertical profile
*
'define t1pm1=lev-pressfc/100'
'set gxout grfill'
'set clevs  -1 1'
'set ccols  1 1'
'set ccols  0 0'
'd maskout(0,t1pm1)'
'set gxout shaded'
------------------------------------------------------------

     Wesley Ebisuzaki
---
and from Mary Jo Nath:
---
How is your topography defined? Is it a separate variable? Or is it
indicated by the grid points with missing values in the field you are
plotting? If it's the missing values, then you can use "const" to
redefine the missing values, then use grfill to color them. I don't know
of a way to just outline them. Hope the example below helps. - MJ

Ex:

* missing value grid points now = 1.; all non-missing values = -var/var
= -1
define tmp=const(-var/var,1,-u)
* mask out the non-topography grid points
define topo=maskout(tmp,tmp)
* color the non-missing grid points in "topo" (the topography)
set gxout grfill
set ccolor 2
d topo

---

Hope this helps,
Chuck

dipak sahu wrote:
> Dear Grads User
>     Is it possible to plot a any parameter like wind following
> two-dimensional terrain in Grads?Actually i want to plot a figure like
> the attached one.
>
>
> with regards
> dipak sahu
>
>
> ------------------------------------------------------------------------
>

--

Please note that Charles.Seman at noaa.gov should be considered my NOAA
email address, not cjs at gfdl.noaa.gov.

********************************************************************
 Charles Seman                                Charles.Seman at noaa.gov
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 Geophysical Fluid Dynamics Laboratory         voice: (609) 452-6547
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