[gradsusr] zonal mean at each latitude

[Joseph Basconcillo]

Dear grads users,

I want to remove the zonal mean from each seasonal mean. Say I have,

'sdfopen hgt_mean_jja.nc'
'set time jun1981 aug 2010'
'd z37'

For each year, say:

'set time jun 1981'

I want to subtract the zonal mean of

0-1N,0-360
1-2N, 0-360E
...
89-90N, 0-360E.

In this sense, I will be able to remove the zonal mean of each latitude from the data. 

After getting the difference, I want to subject the data to EOF analysis.

Can you show me how to do this in GrADS?

Thank you. 

Yours,
Joseph