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Global Simulation of Interaction of the Solar Wind with
the Earth's Magnetosphere and Ionosphere
Tatsuki Ogino
Solar-Terrestrial Environment LaboratoryNagoya University
The Korea-Japan Space Weather Modeling Workshop, 2008, Aug. 12
Space Weather Studies
The Role of Global MHD Simulation of Solar Wind-Magnetosphere Interaction in Space Weather Studies
Satellite anomalies related to Space Weather are on the rise due to the increased use of composite materials instead of metal, and smaller, faster chip designs. The three principle anomaly types are: surface charging, internal charging, and Single Event Effects (SEE).
Satellite anomalies related to Space Weather are on the rise due to the increased use of composite materials instead of metal, and smaller, faster chip designs. The three principle anomaly types are: surface charging, internal charging, and Single Event Effects (SEE).
The Sun’s magnetic field is propagated far beyond our planetary system by the solar wind. The interaction between this interplanetary magnetic field (IMF) and Earth’s own magnetic field is a significant component of Space Weather.
The Sun’s magnetic field is propagated far beyond our planetary system by the solar wind. The interaction between this interplanetary magnetic field (IMF) and Earth’s own magnetic field is a significant component of Space Weather.
The Ionosphere is a layer of the Earth’s upper atmosphere that contains free electrons and ions produced by solar UV radiation. Disruptions of the ionosphere can significantly affect radar, and radio communication.
The Ionosphere is a layer of the Earth’s upper atmosphere that contains free electrons and ions produced by solar UV radiation. Disruptions of the ionosphere can significantly affect radar, and radio communication.
The Sun powers both the space weather and the terrestrial weather machines. Solar events, i.e., explosions of charged particles and the dynamics of magnetic and electric fields, cause huge changes in the near-Earth space environment. Satellites and communication signals must traverse this electric space.
The Sun powers both the space weather and the terrestrial weather machines. Solar events, i.e., explosions of charged particles and the dynamics of magnetic and electric fields, cause huge changes in the near-Earth space environment. Satellites and communication signals must traverse this electric space.
Solar-Terrestrial Environment
FlaresFlares
Solar Solar WindWind
MagnetosphereMagnetosphere
Y. Kamide
Interplanetary Magnetic Field
X-X-raysrays
IonospherIonospheree
Coronal Mass Coronal Mass EjectionsEjections
PolarGeosynchronousGeosynchronous
1. Monitoring of space weather environment
・ Remote sensing of the sun ・ Real-time monitoring of the solar wind and magnetosphere- ionosphere-atmosphere
2. Construction of space weather prediction model
・ Construction of a highly reliable physical model in each region ( Sun, solar wind, magnetosphere, ionosphere, atmosphere ) ・ Establishment of an operational numerical prediction model ・ Unification of different numerical models
Two Important Issues in Space Weather Study
Geospace Study
GeospaceSun-earth system
CMEcoronal hale Solar wind-magnetosphere-
Ionosphere-thermosphere coupling
High energy particles of radiation beltsSolar wind-magnetosphereinteraction
Aurora
solar wind
Space Weather Map
Courtesy of NASA
electron
ionRing current
inner belt
Regional Coupling and Cross-Scale Coupling
1. Solar physics ・ Flare, CMEs ・ Plasma (density, velocity, temperature), photospheric magnetic field ・ Electromagnetic radiation (X ray), high energy particles
2. Space between sun and earth ・ CMEs, shock wave, formation and propagation of interplanetary disturbances ・ Propagation of solar wind and IMF
3. Solar wind and magnetosphere-ionosphere interaction
4. Substorms, magnetic storms, aurora
5. Variation of high energy particles (particles in the radiation belts)
Influence of Solar Activity to Geospace Environment
Solar Activity AtmosphereMagnetosphereSolar Wind Ionosphere
Numerous Space Weather Models are Now Available
Background Solar Wind
SolarProtons
Ring Current/Radiation Belts
Geomagnetic Indices
Coupled Thermosphere -Ionosphere
Global Magnetospheric Simulations
Electrojet Currents
CME Propagation
after Onsager of NOAA/SEC
What are requested to the Sun in Space Weather Study (1) ? Slow phenomena over 1 hour interval
1. Sun-solar wind-geospace interaction
・ Modeling of propagation of the solar wind from solar observations Input : Photospheric plasma (density, velocity, temperature) and photospheric magnetic field Output : Distribution of the plasma and magnetic field in
heliosphere ・ Solar wind and earth’s magnetosphere-ionosphere interaction Simulation of magnetic storms and prediction (Dst) Increase and decrease of the radiation belt particles
2. Unification of sun-solar wind-earth’s magnetosphere interaction models
3. Integration between global model and micro model ・ Variations of the plasma sheet plasma and radiation belt particles
Prediction of Solar Wind Speed and IMF PolarityNick Arge and Vic Pizzo, NOAA/SEC
Input: Solar Photospheric Magnetic Field
Lead Time: 3 – 4 daysCadence: DailyAvailability: Internal Web
Sun
Earth
ACE
Sun
Earth
WIND/ACE
Prediction of Relativistic Electrons Using Solar Wind Speed
Linear Prediction Filter Technique of Baker et al., 1987
Input Kp
Predicted Magnetospheric Electron Flux - 50 keV
What are reguested to the sun in Space Weather Study (2) ? Fast phenomena for about a minute
A reason of separation between solar physics and geospace study in space weather ・ Requirement to know the solar wind (density, velocity, temperature) and 3 components of IMF about every 1 minute in order to predict geospace environment More accurate prediction of substorms and the maximum value of inductive electric field ・ How shorter time interval for variations of the solar wind and IMF can be given from the solar observations and modeling of sun and solar wind ? ・ Is it possible to construct a unifield model of a sun-solar wind-geospace interaction for time interval of a minute ?
Solar wind and earth’s magnetosphere-ionosphere interaction model currently uses satellite observations as input ・ Solar wind (density, velocity, temperature) and 3 components of IMFs every a minute observed by AEC and WIND satellites are used as input of simulation
SunSolar Wind
IMFMagnetosphere Ionosphere
AtmosphereThermosphere
Solar Physics
Solar wind-magnetosphere interaction
M-I Coupling
Thermosphere Model
GSFC/NASANRL, UCLA, MichiganNagoya, NICT, Kyusyu
(KRM, AMIE)
(NCAR et al)
Solar wind-magnetosphere-ionosphere-thermosphere interaction
Physical Simulation Model of Regional Coupling
Flare to CME
CME to Earth
Space Weather Study
magnetosphere
Courtesy of ISAS
sun
Courtesy of NASA
aurora
S t udy relationships betweenthe solar activities and the geospace environment
Relative Location of ISTP Constellation during Sun-Earth Connection Event
SOHO WIND
Geotail
Interball-Tail
Polar
10 Re
100 Re
220Re
EarthSun
ACE
MHD Equations
2)(
Dt
V
Φ
BJVVV
gPt
11)(
PDPPt
PP
2)(
VV
BBVB 2)( t
dBBJ
Density
Momentum
Plasma pressure
Induction
Current
Following MHD Equations are solved as an initial-boundary Problem by Modified Leap-Frog method.
Simulation Model
3-dimensional Global magnetohydrodynamic (MHD) simulation of solar wind-magnetosphere/ionosphere interaction
1. Input
Upstream parameters observed by satellites
2. Output
Prediction of magnetoshere/ionosphere
satellites like GEOTAIL, POLAR, Interball
Ground-based observations
shape, response, distribution of energy・
ACE, WIND, IMP・solar wind and IMF data every 1 minute・
comparison with observations・
00 06 12 18 24 UT
Bz
By
P
Vx
Polar cap electric potential
open-closed boundary
Time evolution of polar cap potential10 minute sampling 1 minute sampling
Bz
By
Dp
Vx
WIND Data
00:00-24:00, 21-22/ 10, 1999
-2500
-2000
-1500
-1000
-500
0
500
Time(minutes)
AUAL
AL, AU Index and Dst Index
00:00 - 24:00, 21-23/ 10, 1999 Dst
-250
-200
-150
-100
-50
0
50
(nT)
Dst
After WDC for Kyoto
Time (hours)
Times of
Minimum value 04:31/22
ALAU
01:19
03:40
Time of Zero value22/21
Times of
Minimum value 06/22
00 12 00 12 24 1 25 49 72
Magnetic storm event for October 21-23, 1999
23:4801:19
03:1604:31
07
every 10 minute sampling
Polar Cap Potential of Every 1 Minute Sampling
Examples of 3D global MHD simulation
southward IMF
northward IMF
3D visualization by VRML (Virtual Reality Modeling Language)
dipole tilt and southward IMF
dipole tilt and northward IMF
Goal of Space Weather Study
1. Construction of unifield physical model from the sun to earth
2. Prediction of indices for magnetospheric disturbances (Dst, AU, AL) and particle distribution in the radiation belts
3. Study of nonlinear phenomena (kinetics) of plasma by unifying the global model and micro (particle) model
4. Proposal of space weather map ・ Diagram of electric potential (or convection) in the polar region ・ Map of plasma distribution (high energy particles) in space from sun to earth