Space Science Reviews

, Volume 196, Issue 1–4, pp 137–166 | Cite as

The Importance of Long-Term Synoptic Observations and Data Sets for Solar Physics and Helioseismology

  • Yvonne Elsworth
  • Anne-Marie Broomhall
  • Sanjay Gosain
  • Markus Roth
  • Stuart M. Jefferies
  • Frank Hill


A casual single glance at the Sun would not lead an observer to conclude that it varies. The discovery of the 11-year sunspot cycle was only made possible through systematic daily observations of the Sun over 150 years and even today historic sunspot drawings are used to study the behavior of past solar cycles. The origin of solar activity is still poorly understood as shown by the number of different models that give widely different predictions for the strength and timing of future cycles. Our understanding of the rapid transient phenomena related to solar activity, such as flares and coronal mass ejections (CMEs) is also insufficient and making reliable predictions of these events, which can adversely impact technology, remains elusive. There is thus still much to learn about the Sun and its activity that requires observations over many solar cycles. In particular, modern helioseismic observations of the solar interior currently span only 1.5 cycles, which is far too short to adequately sample the characteristics of the plasma flows that govern the dynamo mechanism underlying solar activity. In this paper, we review some of the long-term solar and helioseismic observations and outline some future directions.


Sun Observations Helioseismology 



This work utilizes data obtained by the Global Oscillation Network Group (GONG) program, managed by the National Solar Observatory, which is operated by AURA, Inc. under a cooperative agreement with the National Science Foundation. The data were acquired by instruments operated by the Big Bear Solar Observatory, High Altitude Observatory, Learmonth Solar Observatory, Udaipur Solar Observatory, Instituto de Astrofísica de Canarias, and Cerro Tololo Interamerican Observatory. MR acknowledges support from the ORIGIN project, which has received funding from the European Research Council under the European Union’s Seventh Framework Program (FP/2007–2013)/ERC Grant Agreement No. 307117. YE, AMB, MR, and FH acknowledge support from the SpaceInn project, which has received funding from the European Community’s Seventh Framework Programme ([FP7/2007–2013]) under grant agreement No. 312844. YE, SG, MR, and FH acknowledge support from the Solarnet project, which has received funding by the European Commission’s FP7 Capacities Programme for the period April 2013–March 2017 under the Grant Agreement number 312495. YE acknowledges grant support from Science & Technology Facilities Council (UK). SJ acknowledges support from the National Science Foundation under award PLR-1341755. We acknowledge the support from ISSI Bern, for our participation in the workshop.


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Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  • Yvonne Elsworth
    • 1
  • Anne-Marie Broomhall
    • 2
  • Sanjay Gosain
    • 3
  • Markus Roth
    • 4
  • Stuart M. Jefferies
    • 5
  • Frank Hill
    • 3
  1. 1.School of Physics and AstronomyU. BirminghamBirminghamUK
  2. 2.Institute of Advanced Study, U. Warwick, Millburn House, Millburn Hill RoadUniversity of Warwick Science ParkCoventryUK
  3. 3.National Solar ObservatoryTucsonUSA
  4. 4.Kiepenheuer-Institut für SonnenphysikFreiburgGermany
  5. 5.Institute for AstronomyU. HawaiiPukalaniUSA

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