MM5toGrADS README file:

VERSION 3 of MM5 to GrADS converter (release 3-0)
(updated March 7, 2002)

This is the main directory of the MM5 to GrADS conversion programs.
Everything a user needs to run the conversion program, except the
GrADS software, is contained in this directory.
The GrADS software can be obtained from:

http://grads.iges.org/grads/index.html

This version of the MM5 to GrADS converter has been tested on
Linux, Dec, SUN and IBM

All fortran source code is located in the src/ directory.

For upgrades and bug fixes, please read the CHANGES file.

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mm5_to_grads

Version 3.0

Converts MM5 version 3 output files to a format that GrADS can read.
Written by George H. Bryan
Pennsylvania State University
bryan@essc.psu.edu

and Cindy Bruyere
NCAR

Last modified: 8 February 2002

More information, including a "Frequently Asked Questions" file, can
be found at:
http://www.ems.psu.edu/~bryan/mm5/grads/

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How to compile the code.

- Type 'make' in the MM5toGrADS directory to compile;

- When make is successful, executable "grads.exe" will appear in this
directory.

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How to run the code.

1. Change file names in mm5_to_grads.csh

2. Make changes to "namelist.input"

3. Run mm5_to_grads.csh

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A few notes about what what this program does
-or-
How to interpret output from this program
-or-
Don't sue me if you misinterpret your data =)


1) All data are on cross points!
- This is why the xdef and ydef parameters are 1 less than your
I1 (IMAX) and J1 (JMAX) parameters
- U and V are interpolated from dot points to cross points using:
u(i,j) = [ u(i,j)+u(i+1,j)+u(i,j+1)+u(i+1,j+1) ]/4
- This is why variables such as vorticity, divergence, and temp.
advection are output variables from this program: the code computes
u and v derivatives using dot-point data (i.e., it is accurate). If
you compute, say, vorticity in grads using cdiff or hcurl, you are
not truly computing the real vorticity that exists in the raw data.


2) All data are on half-sigma levels!
- Vertical velocity (W) is interpolated onto the half-sigma levels!
- Turbulence kinetic energy (TKE) from the Gayno-Seaman PBL scheme
is also interpolated from full-sigma to half-sigma levels.


Questions, comments, complaints about this code?
Email me: bryan@essc.psu.edu

or, ask mesouser@ncar.ucar.edu

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Files/Directories in this directory:

CHANGES : contain changes made to this tar file
Makefile : top-level makefile
README : basic information
mm5_to_grads.csh: script to run the converter
namelist.input : namelist file requiring user modification
src : directory of source code

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