Current Status of the IAU Working Group on Coordination of Synoptic Observations of the Sun. Alexei A. Pevtsov (National Solar Observatory, USA)

Unified Sun-Earth System Evolving magnetic fields Eruptive events: flares, CMEs, filaments SEPs Irradiance variations […] Different spatial and temporal scales (solar cycle) IMF, Solar wind, ICMEs, Shocks, GCRs and SEPs Magnetosphere Ionosphere Neutral Atmosphere (Climate) […] Source/Sun TransportResponding System Changes in “Responding System”: Geologic/geophysical/ anthropogenic activity Alan Aylward Effect on measurements

Space- vs. Ground-based Day-night /weather cycle/atmospheric seeing effects No, but may have orbital effects Yes, but can be mitigated via use of networks and adaptive optics Extended wavelength coverage Includes EUV, X-ray, in situNo (UV proxies may exist) Longevity< 10 years, critical failures may limit mission Long-term (50 yrs+), instruments can be repaired and upgraded CostHighLow-medium Flexibility of measurements Measurements are fixedNew measurements can be added International collaboration Limited in instrument/ technology development; data analysis is largely unrestricted Requires central coordination Mostly unrestricted Can be run under a loose coordination Space- and Ground-based observations are complementary to each other. Neither is “inferior” or “superior” to the other. Ground-based can serve as a “back-up” to space-based data.

Space Weather Data from Groundbased Instruments Imaging in optical, near infrared wavelengths (350 – 1500 nm) and radio wavelengths Sun-as-a-star high resolution spectroscopy and integrated radio-flux (e.g., 2800 MHz = 10.7 cm) Full disk LOS and vector magnetography (photosphere and chromosphere) Helioseismic observations Various proxies of solar activity (e.g., area/sunspot number, sunspot field strength) Extensive historic records of past solar activity Reconstruction of paleo- solar activity via analysis of radio- isotopes ( 14 C; 10 Be - space climate)

Main international solar monitoring networks SOON/ISOON: visual, WL, H-alpha, 5 stations, NSO-USAF (USA) GONG: helioseismology, magnetograms, WL, H-alpha, 6 stations (NSO, USA) CHAIN:FMT: WL, H-alpha (core-wings), 2 stations + 2 (Hida, Japan) GHN, Global H-alpha High-Resolution Network: informal portal (NJIT, USA) CHAIN SOON/USAF San Vito San Juan, HASTA Antarctica Hida Huairou Learmonth Culgoora HAO Ica Ramey Mt. Chelia Udaipur Yunnan BBSO NSO/SOLIS Holloman GHN GONG Tenerife Cerro Tololo Kislovodsk IrkutskPenticton , Ottawa

SOON (NSO/USAF): – Only organized network – 4 stations – No direct access to data ISOON: Kirkland AFB – Currently only 1 station CHAIN/ Flare Monitoring Telescope (FMT): Hida Observatory (Japan) – Under construction – 3 stations (+ Antarctica?) ISOON FMT

A single dedicated H α portal 8 contributing stations (4 in Europe): daily raw synoptic images

ObservatoryBBSOKANZELHÖHECATANIAMEUDONUcclePic du MidiYUNNANHUAIROU Time zone UTC-8UTC+1 UTC+8 APT10 cm 15 cm25 cm8 cm9 cm18 cm14 cm F/SFilter SpctrgrpFilter B-PASS0.025nm0.07nm0.05/ nm 0.025nm0.05nm<0.05nm0.06nm0.05 nm Range±0.3nm ±0.1 nmN/A±0.25nm * ±0.05nm ±3.2nm CCD2048x x x x Kx2K Bits Cadence1/min – one image 15 min, 1/d, 20/ sec 10 min

UTC 6-7 time zones Non-tunable Uniform data (filters are not uniform) 1-minute cadence

Multiple uncoordinated stations in EU Many European stations, but operating independently on small national budgets Core group of stations in operation: Kanzelhöhe, Uccle, Catania, Paris-Meudon Kanzelhöhe Tatranska-Lomnica Ondrejov Wroclaw Coimbra Pic-du-Midi Paris-Meudon Brussels Utrecht/DOT Rome Hvar Athens Kandili Bucarest Debrecen Locarno Catania Main observatories CCD capability NRT Web images New instrument HaSTeNET?

Current Issues Lack of coordination (non-uniform data, overlap/lack of specific observations) No understanding of what data is needed for Space Weather forecast (need input from forecasters) Current observations are not well-aligned with requirements of SW research/forecast Funding shortages; issues related to “National Security”

Requirements for data? Wavelength ranges Cadence, spatial and spectral resolution Derived parameters (magnetic field/vector or LOS), Doppler velocities? Which data are necessary/supplementary?

Current developments/Future Plans New network to replace GONG/SOLIS (aimed at multi-wavelength helioseismology and vector magnetography) European HaSTeNET? Digitization of historic data (Sac Peak, BBSO, Kodaikanal, MWO, Baikal Astrophys. Observatory) IAU Working Group on Coordination of Synoptic Observations of the Sun Interested in participation? rking_groups/174/