Monthly standardized Cyclone Activity (CAI) 
anomalies from Jan. 1948 - Dec. 2002:

CAIa_60-90N.dat: for the domain from 60N to 90N;
CAIa_70-90N.dat: for the domain from 70N to 90N;
CAIa_60-70N.dat: for the domain from 60N to 70N.