Multiplication and addition of Netcdf files

Question

I have two timeseries netcdf files with the same number of steps:

1. U.nc with variable name u10.
2. V.nc with variable name v10. Now I want to add multiply U.nc with U.nc similarily, V.nc with V.nc.

I also want to add U.nc with V.nc., the variables u10 and v10 should be added.

How can I do this?

Answer 1

you can do it with CDO

Adding u with u:

cdo mul u.nc u.nc ubyu.nc

and

cdo ubyu.nc vbyv.nc usumv.nc

However it seems what you want to do is make the wind vector, for that you can merge the files and then use the expr operator

cdo merge u.nc v.nc uv.nc
cdo expr,'wind=sqrt(u10*u10+v10*v10)' uv.nc wind.nc 

See the tutorial here for more details on the the expr operator

Answer 2

A similar answer to Adrian Tompkins's above.

cdo -L -expr,'wind=sqrt(u10*u10+v10*v10)' -merge u.nc v.nc uv.nc wind.nc 

This uses method chaining. Depending on how CDO was built, you may or may not need -L.