AE, AL, AU and AO geomagnetic indices.
The web site of WDC for Geomagnetism at Kyoto U., url given below,
offers plots and numeric downloads for 1-minute and 1-hour AE and
related indices. Hourly data are available from July, 1957, through
near-current, except for 1976, 1977, and July 1988 through Dec 1989.
One-minute values are available from 1975 forward, with the same
coverage gaps as for hourly data. AL, AU, and AO data start being
available in 1966. The data are currently (as of 12/07/2011)
"final" through June, 1988, and "provisional" through September, 2011.
"Real time" data are available thereafter through another of the
interfaces available through the WDC interface given below. Yet
another such interface provides 2.5 min AE values for 1966-1974.
Alternative sources of many of the WDC/Kyoto-generated AE and related
indices include the 1-min and 1-hour OMNI data sets at
NASA/GSFC/SPDF.