Theory, Modeling and Observation

Theory, Modeling and Observation Event Studies (October 22, 1999)

Conveners: Maha Ashour-Abdalla (UCLA) & Louis A. Frank (Univ. Iowa)

Electromagnetic radiation, plasma flows, and large-scale magnetic fields link the sun to the Earth and its geospace environs. The "weather conditions" of this coupled system fluctuate, sometimes violently, on a variety of time scales. Magnetic storms are the magnetosphere's response to coronal mass ejections (CMEs) and other large-scale solar wind disturbances. CMEs are perhaps the most spectacular manifestations of discrete solar disturbance events and are now thought to occur when the magnetic field lines threading a flare on the sun's surface reconnect, releasing large amounts of energy and causing the flare to erupt. CMEs reaching Earth have a much higher than average solar wind density, which coupled with their strongly southward IMF, can cause major magnetic storms on Earth. One such storm, during which intense aurora were observed at mid-latitudes over the continental USA, occurred on October 21-22, 1999. An interplanetary shock arrived at Earth at 0145 UT on October 21, 1999 compressing the magnetosphere. It was followed by 12 hours of northward interplanetary magnetic field (IMF). At ~2100 UT on October 21, 1999 the IMF turned sharply southward and the solar wind density increased. The geomagnetic disturbances reached maximum near 0700 UT on October 22, 1999 when Dst reached 231 nT. This was followed by the arrival at the Earth of a high-speed stream that continued to affect the Earth for several more days. Several ISTP spacecraft (SOHO, ACE, Wind, Geotail, and Polar), as well as numerous ground stations (e.g. SuperDARN) were well located to study the solar wind, the magnetosphere, the ionosphere, and magnetosphere-ionosphere coupling. This is an ideal interval for storm studies involving observations, theory, and modeling, and is an especially good event with which to test storm time models against observations in the magnetosphere and in the auroral zone.

We would like to encourage everyone, experimentalists and modelers alike, to participate in this session.

Maha Ashour-Abdalla (mabdalla@igpp.ucla.edu)
Lou Frank (louis-frank@uiowa.edu)

AGENDA

Theory, Modeling and Observation Studies (Oct. 21-22, 1999) Part I
Monday, October 23, 2000,  UCLA Faculty Center Sequoia Room
Session: (13:15 - 17:15)
Chairman: L.A. Frank

13:15 - 13:30	Simulation of the September 24-26, 1998 Magnetic Storm (Chuck Goodrich)
13:30 - 13:45	Solar Surface Manifestations (Nat Gopalswamy)
13:45 - 14:00	Observations in the Solar Wind (Jean Berchem)
14:00 - 14:15	Interball Observations During the Geomagnetic Storm of October 21-22, 1999 (David Sibeck)
14:15 - 14:30	Geotail Observations (Lou Frank)

14:30 - 15:00	Discussion

15:00 - 15:15	Polar Identification of Plasma Sheet and Mantle Encounters During the October 1999 Storm Interval (Bill Peterson and Reiner Friedel)
15:15 - 15:30	Relativistic Electron Loss and Stochastic Acceleration (Richard Thorne)
15:30 - 15:45	Energetic Particles Around the Storm Interval 21-22 October 1999 (Bernie Blake)
15:45 - 16:00	GOES Observations of the October 21-22, 1999 Magnetic Storm (Howard Singer)

16:00 -	Discussion


Theory, Modeling and Observation Studies (Oct. 21-22, 1999) Part II
Tuesday, October 24, 2000,  UCLA Faculty Center Sequoia Room
Session: (09:00 - 12:30)
Chairman: J. Berchem

09:00 - 09:15	Injection of <25 keV Ions to the Ring Current During the October 1999 Magnetic Storm (Jim McFadden)
09:15 - 09:30	ENA Observations of the October 22, 1999 Magnetic Storm (Tony Lui)
09:30 - 09:45	Polar VIS Observations (Lou Frank and John Sigwarth)
09:45 - 10:00	Polar UVI Observations (Damien Chua and George Parks)

10:00 - 10:30	Discussion


10:30 - 10:45	Simulation Studies of the October 22, 1999 Storm (Maha Ashour-Abdalla, Mostafa El-Alaoui, Jean Berchem, Ray Walker, Vahé Peroomian, Louis Frank, John Sigwarth and Bill Paterson)
10:45 - 11:00	Simulations of Diffuse Aurora (Margaret Chen and Mike Schulz)
11:00 - 11:15	SuperDARN Observations of the October 21-22, 1999 Storm Period (Kile Baker)
11:15 - 11:30	Waves Observations of the October 21-22, 1999 Magnetic Storm (Stuart Bale)
11:30 -	Discussion

Disclaimer: The following material is being kept online for archival purposes.

Although accurate at the time of publication, it is no longer being updated. The page may contain broken links or outdated information, and parts may not function in current web browsers.

Above is background material for archival reference only.