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Development, analysis and visualization tools for the POM, ECOM and ROMS ocean models (Utilizing NetCDF, MATLAB and AVS)

Rich Signell, John G. Evans and Chuck Denham

Rationale

You've got the model code, but how do you generate a decent grid, store the data in an reasonable way, and analyze/visualize the output? To hopefully save you some work, we've put our machine-independent, extensible software system for generating/editing grids, visualizing and analyzing the model output from ROMS, POM  and ECOM circulation models out here on the Web where you can grab it.

Components of the system:

Component 1. Creating NetCDF output files

To use the Matlab and AVS tools, you need to be write the output using NetCDF , an efficient, self-describing machine-independent binary format that was developed at NCAR's UNIDATA, and is specifically designed for large arrays of scientific data.

• If you've got ROMS or ECOM, you already write NetCDF output, so you are all set.
• If you use POM, you need to add the ability to write NetCDF output files. An example of a routine that can be used as a template is putcdf.f which stores the 4D POM Model output in a NetCDF file, a machine-independent binary format. It might be more convenient to grab the tar-compressed complete NetCDF modified POM97 source code (seamount test case) obtained September 23, 1999 . If you have built NetCDF, you just have to untar, modify the Makefile to point to your NetCDF library, build and go! Check out the comments at the head of putcdf.f or the Readme.txt file for details.

Component 2: Matlab Tools

You can use Matlab to create model grids, edit bathymetry values of the grid, and visualize the NetCDF output files from the model.

• SEAGRID: Matlab tools to interactively build a curvilinear grid.
• GRIDEDIT: Matlab tools to edit bathymetry values.
• OMVIZ: Command line Matlab tools to analyze and visualize NetCDF model output
• CSLICE: GUI Matlab tool to interactively explore the NetCDF model output files, horizontal and arbitrary vertical sections, velocity overlays, zoom, and more.

Component 3: AVS tools

• We built a collection of AVS modules for POM or ECOM that allow 3D extraction, manipulation and volume rendering of the data.

Component 4:  Making movies

How about making movies? Well, just make the frames of your movie with whatever package you like to use, and save each frame as a standard image format, like .gif, .pcx, .ppm, etc. Then use the free FLC making tools to make your movie.