Page Comparison

...

% /bin/cp map_hydro1k_to_ne1024np4_nco.2020040120200210.nc map_hydro1k_to_ne1024np4_nco_fix.2020040120200210.nc
% ncks --frac_b_nrm map_hydro1k_to_ne1024np4_nco_fix.2020040120200210.nc

…

FIXING consistency = 1.0555483035171453 = 1.0+5.6e-02 for grid B cell [17512046,+28.6551,+61.0204]

...

% ncks --dbg_lvl=2 --chk_map map_hydro1k_to_ne1024np4_nco_fix.2020040120200210.nc
...
WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING

...

The new frac_a WARNINGs indicate that the intersection portion of each self-overlapped input gridcell will be weighted less than the portion of the gridcell that is not self-overlapped. This is expected and desired so these WARNINGs may be safely ignored. Again, the locations are printed in a lat,lon format suitable to visualize with Google Maps/Earth. These locations can be used to help identify the root-cause of the overlaps within Grid A.

For reference and reproducibility, see the following files on Cori in ~zender/data/[grids,maps]:

SCRIPgrid_1km-merge-10min_HYDRO1K-merge-nomask_c130402.nc
SCRIPgrid_1km-merge-10min_HYDRO1K-merge-nomask_c130402_ccw.nc
map_hydro1k_to_ne1024np4_nco.20200210.nc
map_hydro1k_to_ne1024np4_nco.20200210_fix.nc

20200423 Update: While writing this documentation we discovered a regression in the NCO weight-generation that produces more (~100+) frac_b WARNINGS than we found in February. Henry Butowsky (Unlicensed) is working to understand and fix the cause of the regression, and will post another update here once more progress is made.