The monthly mean values of the geomagnetic field components at Kakioka are D: -651.2, H: 30131nT, Z: 34984nT and F: 46171nT for April 1991.
Monthly average of the K-index daily sum is 17.1. indicates a high level of geomagnetic activity during the month.
Notable geomagnetic events include 1 magnetic storms, 2 si, 0 bay, 1 sfe, 0 pi and 0 pc.
The international 5 quietest days are the 8,11,13,16,20th.
The international 5 most disturbed days are the 3,4,28,29,30th.
Plot of the geomagnetic hourly value for April 1991
Plot of the K-index daily total sum for 1991
Details of the geomagnetic storms in April 1991
Date | K-index daily sum |
Geomagnetic activity |
Geomagnetic phenomena |
International 5 quietest days |
International 5 quietest days |
geomagnetic 1-minute value plot |
---|---|---|---|---|---|---|
1 | 25 | disturbed | plot | |||
2 | 26 | disturbed | plot | |||
3 | 28 | disturbed | plot | |||
4 | 32 | disturbed | storm | plot | ||
5 | 18 | moderately disturbed | plot | |||
6 | 14 | moderately calm | plot | |||
7 | 12 | moderately calm | plot | |||
8 | 09 | calm | plot | |||
9 | 15 | moderately calm | plot | |||
10 | 17 | moderately disturbed | plot | |||
11 | 09 | calm | plot | |||
12 | 18 | moderately disturbed | plot | |||
13 | 09 | calm | plot | |||
14 | 12 | moderately calm | plot | |||
15 | 08 | calm | plot | |||
16 | 07 | calm | plot | |||
17 | 17 | moderately disturbed | sfe | plot | ||
18 | 18 | moderately disturbed | plot | |||
19 | 18 | moderately disturbed | si | plot | ||
20 | 06 | calm | plot | |||
21 | 12 | moderately calm | plot | |||
22 | 16 | moderately calm | plot | |||
23 | 14 | moderately calm | plot | |||
24 | 17 | moderately disturbed | si | plot | ||
25 | 21 | moderately disturbed | plot | |||
26 | 16 | moderately calm | plot | |||
27 | 20 | moderately disturbed | plot | |||
28 | 23 | disturbed | plot | |||
29 | 31 | disturbed | plot | |||
30 | 26 | disturbed | plot |
*) Plot diagram opens in a separate window.
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