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Real-TimeModellingofCMEsUsingthe
WSA-ENLIL+Cone Model
1
CCMC/SWRC
NASA Goddard Space Flight Center
M. Leila MaysA. Taktakishvili
ModelingCMEswithWSA-ENLIL+Cone
• WSA-ENLILisaglobal3DMHDmodelwhichprovidesatime-dependentdescriptionofthebackgroundsolarwindplasmaandmagneticfieldintowhichasphericalorellipsoidshapedCMEcanbeinserted.
• ACME-likehydrodynamicstructureislaunchedintothesolarwindandmagneticfieldcomputedfromtheWSAcoronalmodelat21.5Rs.
ModelReferences:Arge andPizzo,2000;Arge etal.,2004.Odstrcil etal.1996;Odstrcil andPizzo,1990a,b;Odstrcil,2003.
• WSAcoronalmapsgeneratedfromsynopticmagnetograms providethemagneticfieldandsolarwindspeedattheboundarybetweencoronalPFSSandheliospheric models
• OthercoronalmodelscanalsobecoupledwithENLIL(e.g.MAS,heliospherictomography).
ModelingCMEswithWSA-ENLIL+Cone
• WSA-ENLILisaglobal3DMHDmodelwhichprovidesatime-dependentdescriptionofthebackgroundsolarwindplasmaandmagneticfieldintowhichasphericalorellipsoidshapedCMEcanbeinserted.
• ACME-likehydrodynamicstructureislaunchedintothesolarwindandmagneticfieldcomputedfromtheWSAcoronalmodelat21.5Rs.
ModelReferences:Arge andPizzo,2000;Arge etal.,2004.Odstrcil etal.1996;Odstrcil andPizzo,1990a,b;Odstrcil,2003.
• WSAcoronalmapsgeneratedfromsynopticmagnetograms providethemagneticfieldandsolarwindspeedattheboundarybetweencoronalPFSSandheliospheric models
• OthercoronalmodelscanalsobecoupledwithENLIL(e.g.MAS,heliospherictomography).
ModelingCMEswithWSA-ENLIL+Cone
• WSA-ENLILisaglobal3DMHDmodelwhichprovidesatime-dependentdescriptionofthebackgroundsolarwindplasmaandmagneticfieldintowhichasphericalorellipsoidshapedCMEcanbeinserted.
• ACME-likehydrodynamicstructureislaunchedintothesolarwindandmagneticfieldcomputedfromtheWSAcoronalmodelat21.5Rs.
ModelReferences:Arge andPizzo,2000;Arge etal.,2004.Odstrcil etal.1996;Odstrcil andPizzo,1990a,b;Odstrcil,2003.
• WSAcoronalmapsgeneratedfromsynopticmagnetograms providethemagneticfieldandsolarwindspeedattheboundarybetweencoronalPFSSandheliospheric models
• OthercoronalmodelscanalsobecoupledwithENLIL(e.g.MAS,heliospherictomography).
ENLIL - Schematic Description
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ENLIL – Sumerian God of Winds and Storms
Dusan Odstrcil, GMU & GSFC
Input: WSA (coronal maps of Br and Vr updated 4 times a day). For toroidalcomponents at the inner boundary- Parker spiral.
ENLIL’s inner radial boundary is located beyond the sonic point: the solar wind flow is supersonic in ENLIL.
Computes a time evolution of the global solar wind for the inner heliosphere, driven by corotating background structure and transient disturbances (CMEs) at it’s inner radial boundary at 21.5 Rs.
Solves ideal fully ionized plasma MHD equations in 3D with two additional continuity equations: for density of transient and polarity of the radial component of B.
ENLIL Schematic Description
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ENLILmodeldoesnottakeintoaccounttherealisticcomplexmagneticfieldstructureoftheCMEmagneticcloudandtheCMEasaplasmacloudhasauniformvelocity.
ItisassumedthattheCMEdensityis4timeslargerthantheambientfastsolarwinddensity,thetemperatureisthesame.
Thus,theCMEhasaboutfourtimeslargerpressurethantheambientfastwind.Launchingofanoverpressuredplasmacloudat21.5Rs,roughlyrepresentsCMEeruptionscenario
Output:3D distribution of the SW parameters at spacecraft and planets and topology of IMF.
ConeModelforCMEs
TheCMEconemodelisbasedonobservationalevidencethatCMEhasmoreorlessconstantangulardiameterincorona,beingconfinedbytheexternalmagneticfield,sothatCMEdoesnotexpandinlatitudeinthelowercorona,butexpandsininterplanetaryspacebecauseoftheweakerexternalfield• CMEpropagatesinaradialdirection• CMEbulkvelocityisradialandtheexpansionisisotropic
Zhao etal,2002,ConeModel:
TheprojectionoftheconeonthePOSisanellipse
CMEVandorientationInputtoWSA-ENLIL
Conemodelparameters
• timewhencloudisat21.5Rs
• Latitude
• Longitude
• half-width
• Vr - radialvelocity
InputtoENLILconemodelrun
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Parameters Defined with CCMC CME Triangulation
Tool
CME Parameters: Input To WSA-ENLIL Cone Model
WSA-ENLIL Cone Model
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SWPCCMEAnalysisTool
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CMEImpact– arrival,duration,MPstandoffdistance
Bstop2
2µ0= KnmpV
2
€
rmpRe
=B0Bstop
"
# $ $
%
& ' '
1/ 3MagneticfieldrequiredtostopSW
Magnetopausestandoffdistance
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ACE
12/16/0612/15/06
ram
pre
ssur
e
Time12/14/06
ENLIL
CMEshockarrival–asharpjumpinthedynamicpressure
Durationofthedisturbance–durationofthedynamicpressurehump
nmpV2
Kp IndexPrediction– NewellCouplingFunction
17
Magneticfluxopeningrateatthemagnetopause
Z
€
Kp = 9.5 − exp 2.17676 − 0.000052001dΦMP
dt$
% &
'
( )
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DeterminationoftheCMEArrivalTime– cleararrival
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e-mailwithCMEimpactestimateatEarth
20
e-mailforNASAmissions