Re: GO LAND

[Jonathan Callahan <callahan@xxxxxxxxxxxxx>]

Jeremy,

Thanks for answering this one but I have one correction!

After using the 3-argument shade command you should use "go mp_land" and
not "go land".  The mp_land and mp_fland scripts retain the map
projection used in the 3-argument shade command.

-- Jonathan


Jeremy S Pal wrote:
> 
>   Hi Juan -
> 
> I have done this for a rotated mercator projection.  (Jonathan Callahan
> helped me through this problem when I first started up on ferret.)  The
> procedure was fairly straight forward.
> 
> I am not sure what map projection you use.  (I think non equidistant
> lat-lon projection is not a specific projection.)  But regardless of the
> projection, the procedure should be somewhat straight forward.
> 
> There are two or more ways you can do this:
> 
> (1) The first and easiest is using the 3-argument SHADE, FILL, or CONTOUR
> command, as follows:
> 
>    shade my_data, x_page, y_page
> 
> where x_page and y_page are the latitude and longitude descriptions of
> each data point.  This should plot your data on a standard lat-lon
> grid.  Form there, you can run GO LAND.  See
> http://ferret.wrc.noaa.gov/Ferret/Documentation/Users_Guide/v50/chapter6.html#V5.0_projection
> for more information.
> 
> (2) Now if you want to get fancier, you can also have ferret plot the
> country and land/sea borders on top of your data.  This procedure is a bit
> more complicated.  The nice thing about this method is that portion of the
> map that falls outside of your domain is not plotted.  If you are
> interested method, I am help you through it.  Also, see mp_demo.jnl for a
> demo.
> 
> (3) You could probably interpolate your data onto a lat-lon grid.  This
> may be useful for some purposes (e.g. comparing your model to observations
> which are supplied on a lat-lon grid.).  It should also be fairly easy to
> implement, but I do not know how to do it.
> 
> Let me know if you have any further questions.
> 
>   - Jeremy
> 
> On Wed, 24 Nov 1999, Juan Antonio Prego wrote:
> 
> >     Dear ferreters?
> >
> >     Any experience using go land for non equidistant lat-lon projections?
> >
> >     Ferret is confused and thinks that X and Y axis are longitude and latitude,
> > but they are not, since x=i=1:50 and y=j=1:51. The output is from a REGIONAL model,
> > any experience with that?
> >
> >     Any suggestion about how to change land.jnl script for non equidistant lat-lon
> > projections?
> >
> >     Any help would be greatly appreciated.
> >
> >     Juan
> >
> >
> >
> >