Real-TimeModellingofCMEsUsingthe

WSA-ENLIL+Cone Model

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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

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Magneticfluxopeningrateatthemagnetopause

Z

€

Kp = 9.5 − exp 2.17676 − 0.000052001dΦMP

dt$

% &

'

( )

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DeterminationoftheCMEArrivalTime– cleararrival

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e-mailwithCMEimpactestimateatEarth

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e-mailforNASAmissions