MAJOR MAGNETIC STORMS 1932-1997 ACCORDING TO THE Ap* CRITERIA To view a plot of the number of magnetic storms v.s. sunspots, go to ftp://ftp.ngdc.noaa.gov/STP/GEOMAGNETIC_DATA/APSTAR/magstorm.gif A simpler global index of magnetic activity (other than Kp or Km) is produced in France from the K indices of two nearly antipodal magnetic observatories in England and Australia. ... An AA* index has been derived that is the counterpart of Ap* but is available for the longer span of years. ...