Here we are back :)
So right now I am downloading the 1983-2005 SIS dataset of daily mean for the subdomain of UK.
I will use CDO and R to proccess the data. The final results that I want to have is 12 charts ( from 12 months) showing the temporal variability of the SIS each month and to present the results using visual maps and not charts or wiskey plots. So I would like to see which areas in UK are more reliable ( less variability) and which not reliable ( high variability) as far as the Solar incoming shortwave Radiation.
Unfortunately Jorg the Solar-r package seemed to me a bit complicated and for the time being I think I can obtain the results using the cdo commands that you just described.
The results of this project will be published in the forum resuts.
Thank you.