Synoptic Network Workshop HAONCAR April 2013 Space Weather

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 to temporal 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 filaments helioseismology subsurface evolution surface magnetic evolution

Falconer etal. , SWJ, 2011

Quasi-steady surface field evolution Used as input to WSA global magnetic field 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 Photospheric Field ADAPT Without Active Region Inserted Realization #1 July 1, 2010 Photospheric Field ADAPT Large, GONG detected far-side active region inserted into the ADAPT map on July 1, 2010 With Active Region Inserted

Model Coronal Holes (Before & After Far-Side Active Region Insertion) Derived Coronal Holes ADAPT June 30, 2010 Realization #1 July 1, 2010 Derived Coronal Holes ADAPT Without Active Region Inserted Note coronal hole changes 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” 3 D MHD model, it would really benefit Space Weather applications

WSA Model Schatten Current Sheet Model PFSS Model 5 -30 Rs 2. 5 Rs Outer Coronal Boundary Source Surface Solar Wind Model (e. g. , WSA 1 D Kinematic model, ENLIL, HAF, LFMHelio) (5 -30 Rs to 1 AU)

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) MLSO Radio (on disk ARs) (Vector) magnetograph (photospheric model input) Situational awareness Gross effects, commensurate with quality/quantity of data O 2 R Ejected structure MWA Faraday rotation (n. B for single frequency) Bz (|B| helps) IPS-like Type II-IV