Correlation test for PCA


I have done two independent PCA (Principal component analysis) with two different datasets in R. I have made interpolated geographic maps with the first PC which show the same pattern for both analysis but the comparison solely based on the maps is not enough for me.

I want to do a correlation test between the first PCs of the two analysis to show that there is actually a correlation between the two.

Any suggestion would be highly appreciated.
Tnx alot!