The following table explains the various Space Weather indexes. It is however important to recall that these are for the Space Weather what temperature and pressure are for the Terrestrial ("classic") Weather forecast !
|
Index |
Description |
Range |
Unit |
Updated |
|
ap |
Mean, 3-hourly "equivalent amplitude" of magnetic activity based on K index data from a planetary of 11 Northern and 2 Southern Hemisphere magnetic observatories between the geomagnetic latitudes of 46 and 63 degrees. |
[0 - 400] |
2 nT |
3 hours |
|
Ap |
Daily planetary geomagnetic index obtained by averaging the eight values of ap for each day |
[0 - 400] |
2 nT |
daily |
|
F10.7 |
Solar flux (activity) resulting from its 10.7 cm wavelength observation. This index, thanks to its objective observability, is currently substituting the various Sunspot (see R below) indexes. |
sfu |
||
|
K |
3-hourly quasi-logarithmic local index of geomagnetic activity relative to an assumed quiet-day curve for the recording site. The K index measures the deviation of the most disturbed horizontal component |
[0-9] |
[-] |
3 hours |
|
Kp |
3 hours |
|||
|
R |
daily |
For a more detailed description of the various Space Weather indexes please visit this page from SFI (Finland)
[TABLE TO BE COMPLETED]
[Show comparison between F10.7 and R]