[gradsusr] performing operations on different grids

[Arlindo da Silva]

On Wed, Jul 13, 2011 at 7:19 PM, Jeffrey Duda <jdduda at iastate.edu> wrote:

> I have two 2D model grids that have the same horizontal grid spacing and
> the same domain width (so the X-coordinate is the same between the two) and
> the same domain height, but different numbers of levels in the vertical.  I
> wish to compare the values of some variables such as vertical motion between
> the two model grids.  How do I do that?
>
>
Are the levels really different, or one file is a subset of the other? Say,
one has fewer mandatory levels. If the latter, use lats4d or write your own
simple script to subset the larger file to make it appear as the first. If
the levels are really different, you will need to perform a remapping from
one vertical grid to another. This remap algorithm can vary from a simple
linear interpolation in log-p to a conservative scheme that preserves
monotonicity, all depends on your application. I usually perform this
remapping outside grads.

   Arlindo

-- 
Arlindo da Silva
dasilva at alum.mit.edu
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://gradsusr.org/pipermail/gradsusr/attachments/20110713/2efb5ae3/attachment-0003.html