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Visualization with VisIt

Through a collaboration with the NERSC analytics group and the SciDAC Visualization and Analysis Center (VACET), a plug-in has been developed for the VisIt software for visualization of GCRM data. A description of the plug-in, some samples, and tutorial can be found here. Sample data can be found on our data page. The current plug-in supports cell-centered data.

Analysis with NCO

The NetCDF operators have been enhanced to support operations on GCRM's geodesic data. These enhancements are in version 3.9.5. The -X option has been added to support subsetting in commands such as ncks and ncra. For example, to extract a region from a GCRM data set, the following command can be used: 
ncks -X -145,-90,-15,15 -d level,1 infile.nc -o outfile.nc
Current limitations: Thanks to Charlie Zender and Henry Butowsky for much help with this effort and for substantial performance improvements.

Visualization with VarToImage/VarToKml

We wrote an image generation command-line tool during our Google Earth testing. It has since become an invaluable tool for verifying the data generated by the model runs. The following is the standard help output of the program.

Usage: VarToImage [options] filename [variable name]
Generic options:
-h [ --help ] : produce help message
-o [ --output ] arg : output filename
--useBounds : use cell bounds in cell skip calculation
--useRounding : round, not truncate, float to int casts
Subsetting options:
-t [ --timestep ] arg : which timestep to read
-l [ --level ] arg : which level to read
-b [ --box ] arg : "north,south,east,west" limits in degrees
Image/color options:
-s [ --size ] arg : "Width[xHeight] of image, ex) 1024x768, or 360
-r [ --range ] arg : "min,max" data value limits (outliers are black)
-f [ --fit ] : reduce image size to implicit box size
-c [ --colorMode ] arg : 0 = ROYGBIV (rainbow) 1 = GRADIENT_TO_WHITE 2 = GRADIENT_TO_TRANSPARENT
-C [ --invertColor ] : ex) ROYGBIV becomes VIBGYOR
-g [ --gradient ] arg : "r,g,b" gradient color
-d [ --drawEdges ] : draw cell edges, when on default color is black
-e [ --edge ] arg : "r,g,b" cell edge color, implicitly enables drawing
-L [ --label ] : Add 8pt label to each cell with the cell value (or index)
-S [ --labelSize ] arg (=8) : Default 8(pt)

VarToImage/VarToKml examples