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Synoptic Network Workshop(HAO/NCAR, April 2013)
Space Weather and Synoptic Observations
V J Pizzo – NOAA/SWPC
Space Weather in the Narrow Sense
Acute, short-term variations in inner heliospheric conditions due totemporal changes in solar outputs
Not Space Seasons
Not Space Climate
Space Weather Operations entails
• Nowcasting – monitoring and characterizing current events to support advances at a later date
• Forecasting – using ground and space-based observations, coupled with modeling, to predict course of events at Earth or other locations
Main solar drivers of space weather in the inner heliosphere include:
• Hard photon radiation (X-ray, EUV)(upper atmosphere, s/c)
• Energetic particles (prompt protons) (s/c, astronauts)
• CIRs, CMEs in solar wind flow (geomagnetic)
Active (transient) solar phenomena, which are the source of the most spectacular manifestations, take place in the context of the slower, overall evolution of the Sun
Hence, synoptic observations are the cornerstone in the development of Space Weather understanding and applications
Thus, from the operational perspective, the question to be addressed at this workshop is:
“Which ground-based observations couple best with space-based observations and models for Space Weather application needs?”
“…Space Weather application needs?”
It needs to be emphasized that which may work quite well for Space Weather applications may seem inadequate in terms of basic research
Operational philosophy:
“What works is good enough (for now)”
The question is less “why” than “how”
You do not have to understand something to make effective use of it
Consider the ancients:- seasons, eclipses- samurai sword making (folding)
Predicting AR eruptions
Associated with flares, radiation, particles, & CMEs
sunspot classification (“δ”-spots)eruptive filamentshelioseismology
subsurface evolutionsurface magnetic evolution
Falconer etal., SWJ, 2011
Quasi-steady surface field evolution
Used as input to WSA global magneticfield model
Provides ambient for Enlil CME propagation model in operations at NOAA and elsewhere
Depends upon ground-based observations (primarily GONG, but could use SDO HMI)
GONG is especially useful because of- consistency- availability- calibration
These also make it ideal for ADAPT approach- intelligent assimilation of data stream- ensemble output
Two biggest shortcomings of current ambient flow simulations
1) polar holes are poorly observed- LOS field component- annual orientation effects
2) uses front-side data only- “oldest” data at E limb- especially vexing when new ARs
appear on backside, near E limb- helioseismology fix?
Photospheric Field (Before & After Far-Side Active Region Insertion)
June 30, 2010
July 1, 2010
Large, GONG detected far-side active region inserted into the ADAPT map on July 1, 2010
Ph
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Realization #1
Without Active Region Inserted With Active Region Inserted
Model Coronal Holes(Before & After Far-Side Active Region Insertion)
June 30, 2010
July 1, 2010
Der
ived
Co
ron
al H
ole
sA
DA
PT
Der
ived
Co
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al H
ole
sA
DA
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Der
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Co
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sA
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Note coronal hole changes
Realization #1
Without Active Region Inserted With Active Region Inserted
…except for that other minor detail:
3) Net open fluxes are too low (factor of ~2)
Does not appear to be specific WSA issue
Other models driven by same solar surface data appear to show similar behavior
Possible resolution
Open flux associated with slow solar wind flow may not be properly accounted for in either WSA or most coronal MHD models
In WSA, just “edge” of coronal hole
If such open flux could be parameterized into a simple model, either extension of WSA or a “reduced” 3D MHD model, it would really benefit Space Weather applications
Solar Wind Model
(e.g., WSA 1D Kinematic
model, ENLIL, HAF, LFM-
Helio)(5-30Rs to
1AU)
Source Surface
PFSS Model
Schatten Current Sheet Model
5-30 Rs
2.5 Rs
Outer CoronalBoundary
WSA Model
Magnetic input for CMEs
Insufficient work done on CMEs with MC in IP space, many significant numerical problems remain, but key issue is
What MC is ejected for a given CME?
Infer magnetic structure from near-surface disk observations or via radio-wave Faraday rotation?
Bz is the goal, but could |B| be reliably obtained?
IPS, other observations
Coronal fields
IR (limb) MLSORadio (on disk ARs)(Vector) magnetograph (photospheric model input)
Ejected structure
MWAFaraday rotation (nB for single frequency)Bz (|B| helps)
IPS-like
Type II-IV
Situational awarenessGross effects, commensurate with quality/quantity of dataO2R