1. Yama's works Using geomagnetic data
(Halloween) event: quick development in 6 min.
event: Isolated southward IMF propagation.
SSN-K (and SSN-Kp) relation: non-linearly low since 2004
event: PC-5 pulsation affecting ions
event: Sunward propagating structure = aurora

2. => SW = 2000 km/s
event

3. Kiruna data gives most smooth curve

4. Ground ∆B + auroral image
0611:40 UT
0615:40 UT
evening-midnight
Ground ∆B + auroral image
IQA≈01 LT
0613:40 UT
morning
0617:40 UT

5. Extremely low solar activity since last solar minimun
 Effect on the Earth?
(SCOSTEP VarSITI program)
Kiruna (65° GMLat) K index during the current maximum #24 (2011~) is nearly the same as values at solar minimums.
note: UT means LT, and magnetic midnight sector when aurora activity causes large K. 5

6. SSN – Kp (subdivided by different phases)
Min
Incl.
Max
Decl.
1. Each solar cycle must be subdivided by different phases (because the solar wind condition is different for the same SSN)
2. Kp since 2004 are the lowest for the same SSN 6

7. Reconstruct Kp from SSN
(note: subdivide by different phases)
⇒ reconstruct within standard deviation except the recent 10 years.
⇒ change from 2004 is clear 7

8. “Chance of minor storm@high-latitude” by NOAA vs. observed Kp
(Anna Larsson, high-school student project)
% of observed Kp (largest of the day)
For the same prediction, Kp values are (model is different between 2000 ⇔ 2011): < & < 8

9. 2000-11-08 event Unique IMF Bz=+10 nT  -3 nT  +10 nT change
Only once in 50 year’s Kiruna data (examined all data from 1954)
All polar geomagnetic stations showed similar signature, propagating tailward with the solar wind velocity
Presented at EGS 2001 (EGU = EGS + EUG), but could not publish because I got sick when I finished analyses

10. solar wind

11. X
Kiruna Y Z AU AL

12. 1986-9-12 event Finland = conjugate + online
Kiruna = only analogue data
event
Viking conjugate

13. Viking

14. event

15. overview ions > 5000 km/s ions ≈ 3000 km/s P/A 0.01~40 keV P/A
06:42
06:44
06:46
06:48
IMAGE
(FUV)

16. AE and Bx Main phase of minor storm (Dst ~ -60 nT).
2. Substorm onset at around 06:25 UT but ceased in ~10 min.
3. New activity started at around 06:38 UT.
4. Aurora bulge arrived Cluster’s conjugate ~19 MLT at around 06:42~06:44 UT.

17. sunward propagation
1000~2000 km

19. Misato Aurora Camera

20. Misato Aurora Camera