Regriding Reanalysis Data

A frequent task while working with different reanalysis datasets is to put two .nc files in the same coordinate system. Specifically in this post we will regrid a .nc file from CMIP5 project in gaussian coordinates to lonlat coordinates based in NCEP reanalysis.

First of all, the easiest way to clone a grid is by using the wonderful tool set of cdo for Ubuntu. It is just like running

cdo griddes air_mon_mean.nc > myGridDef.txt

It will create a file myGridDef based on current grid specification of your base data set (in this case, air_mon_mean.nc). It have all required references to create your new grid.

Now, using the same cdo tool set, we can remap any .nc file in a different grid using a bilinear interpolation technique

cdo remapbil,myGridDe.txt air_mon_mean.nc air_mon_mean_regrid.nc

Thats it!