Cubed-Sphere Data Access Guide

Cubed-Sphere grid background

The GEOS-5 now has products that are stored natively in cubed-sphere grid. The utilities here may help users visualize the data in cubed-sphere or map the data to lat-lon grid.

Fortran

To map the cubed-sphere grid data to lat-lon gird data, the program c2l_CFIO_offline.x is built with AGCM at src/GEOSgcs_GridComp/GEOSgcm_GridComp/GEOSagcm_GridComp/GEOSsuperdyn_GridComp/FVdycoreCubed_GridComp. The example configure file c2l_CFIO_offline.rc is also generated. It should be run as mpirun –np 6 ./c2l_CFIO_offline.x. This will produce a lat-lon grid data file whose name is configured in c2l_CFIO_offline.rc

Matlab

Users can find a “GridUtils” package in MATLAB ( R2015b and R2016a) at http://wiki.seas.harvard.edu/geos-chem/index.php/GEOS-Chem_HP_Output_Data#MATLAB_.28Cubed-sphere_and_regular_data.29 . The instructions are straight forward. Although it is intended for GCHP, it can be used for all the other outputs that uses the same formats as that of GCHP.

IDL

Dr. Bill Putman has created many IDL programs to visualize GEOS-5’s outputs. Users may find some useful tools at /discover/nobackup/projects/gmao/osse2/IDL3 . The program read_and_interpolate_cube.pro can read data in the cube-sphere grid in NetCDF file, interpolate the data , map the data in Lat-Lon format and plot. The program cube_to_latlon.pro can use read_and_interpolate_cube.pro to convert the variables in cube-sphere grid to lat-lon grid and write the variable to NetCDF files.

GrAds

To use GRADS to display cube-sphere grid data in a NetCDF file, the path should be in the PATH environment: /discover/nobackup/projects/gmao/share/dasilva/opengrads/Contents/grads

Then the users can follow the steps: 1) run src/GMAO_Shared/GEOS_Util/plots/configure. This will produce a .quickplotrc in that directory 2) source .quickplotrc 3) run grads. 4) run command dc to plot the cube-sphere grid NetCDF file. Users can get help by just run dc without any argument.