Measure of anomalousness (MA indicator)

The resulting values of the MA indicator are the values of the measure of anomality for each of the geomagnetic vector components (X, Y, Z, F or H, D, Z, F) for a 1-minute time interval. Evaluation of geomagnetic activity by calculations of MA is performed every time when new fragments of 1-minute or 1-second data are received at the database. Data are analyzed within a 3-day time interval of the record from current moment backwards.

Currently used grades and corresponding threshold values for this indicator are listed in the following table:

Grade	Minimum value	Maximum value
0	-1	0.4
1	0.4	0.55
2	0.55	0.7
3	0.7	1

For more details, please check our paper in the Annals of Geohysics journal:

A. Soloviev, S. Agayan, S. Bogoutdinov, Estimation of geomagnetic activity using measure of anomalousness, Annals of Geophysics, 59 (6), 2016.