There are several indices that are used as indicators of magnetic activity. Most of these are available through NGDC or NSSDC. The following is a list of the more common indices and where they reside.
aa
Average of K indices (converted to nT) for two Antipodal observatories.
Additional 3-hourly values can be obtained through NGDC at their anonymous FTP
site:
ftp.ngdc.noaa.gov/STP/SOLAR_DATA/RELATED_INDICES/AA_INDEX
Available: 3-hourly 1868 - 1986 (units: nT)
CD: NGDC001
Files: geomag3/indices/aa
AE
Measure of Auroral Electrojet current based on range of H disturbance for auroral zone observatories. Additional hourly and one-minute values can
be obtained through NGDC at their anonymous FTP site: ftp.ngdc.noaa.gov/STP/GEOMAGNETIC_DATA/INDICES/AURORAL_ELECTROJET
Available: hourly 1957 - 1983 (units: nT)
CD: NGDC001
Files: geomag3/indices/ae
An/As/Am
Average of K indices (converted to nT) for groups of observatories in
the northern and southern hemispheres. Additional 3-hourly values can
be obtained through NGDC at their anonymous FTP site:
ftp.ngdc.noaa.gov/STP/SOLAR_DATA/RELATED_INDICES/AA_INDEX
Available: 3-hourly 1959 - 1982 (units: nT)
CD: NGDC001
Files: geomag3/indices/amns
ap
Equivalent Amplitude index of Kp values (converted to nT). Additional
3-hourly values can
be obtained through NGDC at their anonymous FTP site:
ftp.ngdc.noaa.gov/STP/GEOMAGNETIC_DATA/INDICES/KP_AP
Available: 3-hourly 1932 - 1997.1 (units: 2 nT)
CD: NGDC001,MODELS001
Files: geomag3/indices/kp
indices/kpap
Ap
Average of the 8 ap values. Additional 3-hourly values can
be obtained through NGDC at their anonymous FTP site: ftp.ngdc.noaa.gov/STP/GEOMAGNETIC_DATA/INDICES/KP_AP
Available: daily 1932 - 1997.1 (units: 2 nT)
CD: NGDC001,MODELS001
Files: geomag3/indices/kp
indices/kpap
Dst
Disturbance Storm Time is a measure of the ring current determined from
low-latitude observatories. Additional hourly values can be obtained
through NGDC at their anonymous FTP site:
ftp.ngdc.noaa.gov/STP/GEOMAGNETIC_DATA/INDICES/DST
Available: hourly 1957 - 1993 (units: nT)
CD: MODELS001
Files: indices/dst57
F10.7
Ottawa 10.7 cm solar radio flux. Additional daily values can be obtained
through NGDC at their anonymous FTP site:
ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SOLAR_RADIO/FLUX
Available: daily, monthly, yearly 1947 - 1989 (units: 10E-22 Joules/second/meter squared/Hertz)
CD: NGDC001, MODELS001
Files: solar/radio/ottawa
indices/avgf107
Kp
Average of K indices (range of H components) of global sub-auroral zone
observatories. Kp range: [0o, 0+, 1-, ... 9-, 9o].
Additional 3-hourly values can
be obtained through NGDC at their anonymous FTP site: ftp.ngdc.noaa.gov/STP/GEOMAGNETIC_DATA/INDICES/KP_AP
Available: 3-hourly 1932 - 1997.1
CD: NGDC001,MODELS001
Files: geomag3/indices/kp
indices/kpap
Kn/Ks/Km
Average of K indices for groups of observatories in
the northern and southern hemispheres. Additional 3-hourly values can
be obtained through NGDC at their anonymous FTP site:
ftp.ngdc.noaa.gov/STP/SOLAR_DATA/RELATED_INDICES/AA_INDEX
Available: 3-hourly 1959 - 1982
CD: NGDC001
Files: geomag3/indices/kmns
ssn
Sun Spot Number is a measure of the area of solar surface covered by spots.
Additional daily, monthly, and yearly values can be obtained through NGDC at their anonymous FTP site:
ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SUNSPOT_NUMBERS
Available: daily, monthly, yearly 1610 - 1995
CD: NGDC001,MODELS001
Files: solar/sunspot
indices/ssn
tilt
Dipole Tilt Angle is the angle between the dipole axis and the Earth-sun
line. Any value can be computed with the program tilt2.f
Available: hourly 1960 - 1989 (units: degrees)
CD: MODELS001
Files: indices/tilt