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AFRL/CISM CollaborationsAFRL/CISM Collaborations

Nick ArgeNick ArgeSpace Vehicles Directorate

Air Force Research Laboratory

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Center for Integrated Space Weather Modeling (CISM)Center for Integrated Space Weather Modeling (CISM)

CISM: NSF funded consortium to construct a comprehensive physics-based numerical simulation model that describes the space environment from the sun to the earth.

CISM Member Institutions

AFRL/CISM Collaborations:• Partnership on science and model development.• Application of CISM products to AF interests to facilitate

transition to operations.

Magnetosphere (Perry, Ginet, Hudson, Albert, Young) • Validation of GEO MeV electron forecast models.• Integrate radiation belt particle & diffusion models with coupled LFM MHD & RCM codes.

Ionosphere (Stan Solomon et al./Odile de la Beaujardiere, John Retterer, Keith Groves) • Couple CISM ionosphere model with C/NOFS "bubble calculator.” • Compare scintillation results with SCINDA and C/NOFS data.

Solar (Arge, Odstrcil, Geymehr, Owens, Spence, McGregor) • The Wang-Sheeley-Arge (WSA) coronal/ solar wind model. • WSA+ENLIL coupling.

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Plot courtesy Sarah McGregor (BU/CISM)

Solar Wind Model

(e.g., 1D Kinematic

model, ENLIL, HAF)

(5-30Rs to 1AU)

Source Surface

PFSS Model

Schatten Current Sheet Model

5-30 Rs

2.5 Rs

WSA Coronal & Solar Wind ModelWSA Coronal & Solar Wind Model

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PFSSPFSS++SCS MODEL (R = 5.0 SCS MODEL (R = 5.0 RR)) Predicted Solar Wind Speed at 5.0 Predicted Solar Wind Speed at 5.0 RR

(New Empirical Relationship )(New Empirical Relationship )

5.3

5.7θ1

3/1

3

6.18.51

5.1265θ,

b

ef

fVs

bskm s-1

Where:

fs = Magnetic field expansion factor.

θb = Minimum angular distance that an open field footpoint lies from nearest coronal hole boundary (i.e., Angular depth inside a coronal hole)

WSA Model Coronal OutputWSA Model Coronal OutputC

oron

al H

oles

Cor

onal

Fie

ld (

5.0R

)

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IMF directed radially toward from Sun.

IMF directed radially away from Sun.

Solar Wind Speed and IMF Polarity in the Ecliptic Solar Wind Speed and IMF Polarity in the Ecliptic Driven by Daily Updated Photospheric Field MapsDriven by Daily Updated Photospheric Field Maps

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Solar Wind Speed Predictions & ObservationsSolar Wind Speed Predictions & Observations IMF Polarity Predictions & ObservationsIMF Polarity Predictions & Observations

Predictions & Observations:Near Solar MaximumPredictions & Observations:Near Solar Maximum

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Solar Wind Speed Predictions & ObservationsSolar Wind Speed Predictions & Observations IMF Polarity Predictions & ObservationsIMF Polarity Predictions & Observations

Predictions & Observations:Near Solar MinimumPredictions & Observations:Near Solar Minimum

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Validated 8 years of WSA predictions Event-based approach: high speed enhancements (HSE):

Captures more than 72% of the observed HSE events Most of the false HSEs are small Missed HSEs: are small events or transients Timing of HSEs shows no offset. Slight underestimation of magnitude

of fastest events – probably due to transients

Observed

HSE No HSE

Model

HSE 166 36

No HSE 64 -

Contingency Tables

Missed

False

Observed

Model

Boston University Boston University ValidationValidation of WSA Event-Based of WSA Event-Based Approach: (High Speed Events)Approach: (High Speed Events)

( Owens et al., JGR 2005)( Owens et al., JGR 2005)

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Validating Coronal Models Using Coronal HolesValidating Coronal Models Using Coronal Holes

Solar Minimum Solar Maximum Short After Solar Maximum

MAS/SAIC

de Toma, Arge, and Riley (2005)

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WSA Coronal - ENLIL MHD Solar Wind WSA Coronal - ENLIL MHD Solar Wind Model CouplingModel Coupling

Output of WSA MODEL Output of WSA MODEL (R = 21.5 (R = 21.5 RR))

Coronal Field Strength

Solar Wind Speed

ENLIL 3D MHD Solar Wind ModelENLIL 3D MHD Solar Wind Model

Output of ENLIL MODEL at 1AUOutput of ENLIL MODEL at 1AU

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1) AFRL and CISM collaborating/partnering on science and model development.

Solar, Magnetosphere, & Ionosphere realms.

Application of CISM products to AF interests to facilitate transition to operations

2) The WSA model

Predicts ambient solar wind speed and IMF polarity 1-7 days in advance.

Serves as the CISM baseline coronal/solar wind model.

Solar wind predictions validated using 8 years (~1 solar cycle) of predictions.

Coronal hole predictions compared with observations and MAS/SAIC MHD model.

Running in real-time at NOAA/SEC, CCMC, and AFRL(AFWA).

Officially delivered to CISM in Dec. 2005.

3) Joint AFRL-CISM effort to couple the WSA+ENLIL model.

Useful forecasting tool and basic research model.

SummarySummary