WDC-SILSO: An unprecedented modernization of the sunspot record - PowerPoint PPT Presentation

ROB STCE WDC-SILSO: An unprecedented modernization of the sunspot record Frédéric Clette, Laure Lefèvre World Data Center SILSO, Royal Observatory of Belgium, Brussels

Sunspot number: origins and applications RADIO SPACE TELESCOPE: VISUAL PHOTOGRAPHY CCD SMALL GRAND MINIMUM MINIMUM (Dalton) (Maunder) • Longest record of solar activity (400 years) • Historical observations back to 1610 (telescope) • Continuously extended: worldwide network of 85 stations • Unique long-term reference: > 100 publications/year: – Solar physics (physical modeling of solar 11-year cycle) – Climatology (secular solar forcing to Earth climate) – Industry and defense : telecoms, navigation, space, electrical power 11/9/2016 2016 WDS Forum, Denver 2

SILSO data products and Web portal • Sunspot Number (1700-present): – Daily, monthly, yearly – Total and hemispheric • Mid-term forecasts : – 12-months ahead – 2 methods • New products: – Group Number (1610 – 1995): • Only group counts – Real-time Estimated Sunspot Number (EISN) 11/9/2016 2016 WDS Forum, Denver 3

A full modernization • New Web site (January 2015) : – Data documentation, FAQ – New improved graphics – Ready for extensions • Refurbished software and archives : – FORTRAN to Python code (bug fixes!) – Databases (MySQL): > 530,000 obs. – Web-based data input GUI • Full recalibration of the primary sunspot number series: – First-ever full revision ! – Undertaken in 2011 – 50 international experts – 4 workshops • Corrections by up to 40% 11/9/2016 2016 WDS Forum, Denver 4

First-ever end-to-end recalibration • Review paper: Clette, F., Svalgaard, L., Vaquero, J.M., Cliver, E.W.: 2014, Revisiting the Sunspot Number. A 400-Year Perspective on the Solar Cycle. Space Sci. Rev. 186, 35-103 • Official release in July 2015 – IAU General Assembly (Aug. 8, 2016) • Implementation of data set versioning • Full revival of long-term solar cycle research : – Topical Issue (“Solar Physics” journal): Publ.: December 2016 > 40 papers, 800 pages – Since 2014, publication of multiple alternate sunspot series by various teams 11/9/2016 2016 WDS Forum, Denver 5

A profound transition: multiple new roles Static unquestioned archive Modern evolving data set Formerly (Zurich, SIDC) Repository + extension of the heritage series (frozen method) Now (WDC –SILSO) Clearinghouse for all new published results (whole series) • Central hub for input sunspot data (database of all raw observations) • Coordinated evaluation of future proposed corrections (IAU supervision) • Upgrade of the production method to follow progresses 11/9/2016 2016 WDS Forum, Denver 6

The future: bright but uncertain • Promising prospects: – Full quality assurance – Extension by image- based sunspot indices (sunspot catalogs) Zharkova et al. EGSO, 2003 • But … SILSO in a precarious situation! – No structural funding – Insufficient manpower (team of only 3 part-time collaborators) DigiSun drawing measurement tool ROB, Brussels 11/9/2016 2016 WDS Forum, Denver 7

Questions or suggestions ? Poster # 61 World Data Center – SILSO Sunspot Index and Long-term Solar Observations http://sidc.be/silso 11/9/2016 2016 WDS Forum, Denver 8