Science Topics:
Sun – Storm Relationships:
1) How does the probability of observing major magnetic storms change with time, and what is the underlying physics, e.g.,
- Season (e.g., Is there a seasonal variation in the rate of major storms? What is the relative importance of the Russell-McPherron effect (the tilt of the dipole orthogonal to Earth-Sun line relative to solar equator) as compared to the equinoctial effect (tilt of the dipole in GSM x-z plane relative to the Earth-Sun line)?
- Phase of the solar cycle (e.g., variation in ICME/magnetic cloud properties through the solar cycle; solar activity levels),
- From cycle to cycle?
2) What are the properties of the solar events that give rise to (most) major geomagnetic storms, e.g., (This is really the key output of WG1 for the workshop!)
- Location on the Sun (do limb events ever cause major storms?)
- Properties of associated X-ray, H-alpha flares;
- Properties of associated CMEs.
- Relationship with major solar energetic particle events?
- What is the probability that halo CMEs give rise to major storms?
- Are there any properties of the solar events that correlate with the storm strength (e.g., Dst)?
3) Solar wind – Magnetospheric coupling (also of interest to WG2)
- What are the different types of IP structures that drive major storms, and what observations/predictions would be needed to “forecast” such storms?
- Is there a “typical” CME magnetic storm profile in Dst? Is a statistical approach to forecasting Dst profiles useful?
- Does magnetospheric coupling depend on solar wind dynamic pressure, density, Alfven Mach number? Do such factors change the amount of energy input to the magnetosphere and hence the strength of Dst in particular storms?
WG4 Events of particular interest:
9 May
4 1998
18 Jan.
13 1999
25 April
7 2000
29 Aug.
12 2000
58 Oct.
1 2002
59 Oct.
4 2002
76 July 27 2004