|Auroral Electrojet Indices Designed to Provide a Global Measure, 2.5-Minute Intervals,
of Auroral Zone Magnetic Activity
|The Auroral Electrojet index (AE) is designed to provide a global quantitative measure
of auroral zone magnetic activity produced by enhanced ionospheric currents flowing
below and within the auroral oval. Ideally, it is the total range of deviation at
an instant of time from quiet day values of the horizontal magnetic field (H) around
the auroral oval. The indices are derived in response to a need voiced by scientific
users. These indices are computed from a network of geomagnetic observatories, some
recording digitally and others as analog, which encircle the northern auroral zone.
The AE computation uses horizontal magnetic field values measured at 2.5-minute intervals.
AE plus the supplemental indices AL, AU and AO are included in this data file.