Skip to main content
SpringerLink
Log in

The Ratio Between the Number of Sunspot and the Number of Sunspot Groups

  • Published:
Geomagnetism and Aeronomy Aims and scope Submit manuscript

Abstract

Data from three solar observatories (Learmonth, Holloman, and San Vito) are used to study the variations in the average number of sunspots per sunspot group. It is found that the different types of sunspot groups and the number of sunspots in these groups have different solar cycle and cycle to cycle variations. The varying ratio between the average number of sunspots and the number of sunspot groups is shown to be a real feature and not a result of changing observational instruments, observers’ experience, calculation schemes, etc., and is a result of variations in the solar magnetic fields. Therefore, the attempts to minimize the discrepancies between the sunspot number and sunspot group series are not justified, and lead to the loss of important information about the variability of the solar dynamo.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Clette, F., Berghmans, D., Vanlommel, P., Van der Linden, R.A.M., Koeckelenbergh, A., and Wauters, L., From the Wolf number to the International Sunspot Index: 25 years of SIDC, Adv. Space Res., 2007, vol. 40, no. 7, pp. 919–928.

    Google Scholar 

  • Clette, F., Svalgaard, L., Vaquero, J.M., and Cliver, E.W., Revisiting the sunspot number. A 400-year perspective on the solar cycle, Space Sci. Rev., 2014, vol. 186, nos. 1–4, pp. 35–103.

    Article  Google Scholar 

  • Cliver, E.W., Clette, F., and Svalgaard, L., Recalibrating the sunspot number (SSN): The SSN workshops, Cent. Eur. Astrophys. Bull., 2013, vol. 37, pp. 401–416.

    Google Scholar 

  • Curto, J.J., Solé, J.G., Genescà, M., Blanca, M.J., and Vaquero, J.M., Historical heliophysical series of the Ebro observatory, Sol. Phys., 2016, vol. 291, nos. 9–10, pp. 2587–2607.

    Article  Google Scholar 

  • Georgieva, K., Kilcik, A., Nagovitsyn, Yu., and Kirov, B., About the recalibration of the sunspot record, 2017. https://arxiv.org/abs/1701.06165.

    Google Scholar 

  • Hoyt, D.V. and Schatten, K.H., Group sunspot numbers: A new solar activity reconstruction, Sol. Phys., 1998, vol. 179, pp. 189–219.

    Article  Google Scholar 

  • Kilcik, A., Yurchyshyn, V.B., Abramenko, V., Goode, P.R., Ozguc, A., Rozelot, J.P., and Cao, W., Time distributions of large and small sunspot groups over four solar cycles, Astrophys. J., 2011, vol. 731, 30. doi 10.1088/0004-637X/731/1/30

    Article  Google Scholar 

  • Kilcik, A., Yurchyshyn, V.B., Ozguc, A., and Rozelot, J.P., Solar cycle 24: Curious changes in the relative numbers of sunspot group types, Astrophys. J., 2014, vol. 7941, L2. doi 10.1088/2041-8205/794/1/L2

    Article  Google Scholar 

  • Leighton, R.B., Observations of solar magnetic fields in plague regions, Astrophys. J., 1959, vol. 130, pp. 366–393.

    Article  Google Scholar 

  • Nagovitsyn, Yu.A., Pevtsov, A.A., and Livingston, W.C., On a possible explanation of the long-term decrease in sunspot field strength, Astrophys. J. Lett., 2012, vol. 758, no. 1, L20.

    Article  Google Scholar 

  • Penn, M. and Livingston, W., Long-term evolution of sunspot magnetic fields, 2011. https://arxiv.org/abs/1009.0784.

    Google Scholar 

  • Pevtsov, A.A., Nagovitsyn, Yu.A., Tlatov, A.G., and Rybak, A.L., Long-term trends in sunspot magnetic fields, Astrophys. J. Lett., 2011, vol. 742, no. 2, L36.

    Article  Google Scholar 

  • Sheeley, N.R. Jr., Measurements of solar magnetic fields, Astrophys. J., 1966, vol. 144, pp. 723–732.

    Article  Google Scholar 

  • Svalgaard, L. and Schatten, K., Reconstruction of the sunspot group number: The backbone method, Sol. Phys., 2016, vol. 291, nos. 9–10, pp. 2653–2684.

    Article  Google Scholar 

  • Tlatov, A.G., Long-term variations in sunspot characteristics, Geomagn. Aeron. (Engl. Transl.), 2013, vol. 53, no. 8, pp. 953–956.

    Article  Google Scholar 

  • Usoskin, I.G., Solanki, S.K., and Kovaltsov, G.A., Grand minima and maxima of solar activity: New observational constraints, Astron. Astrophys., 2007, vol. 471, no. 1, pp. 301–309.

    Article  Google Scholar 

  • Waldmeier, M., The sunspot-Activity in the Years 1610–1960, Zürich: Schulthess, 1961.

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. SRTI-BAS, Sofia, Bulgaria

    K. Georgieva & B. Kirov

  2. Akdeniz University, Antalya, Turkey

    A. Kilçik

  3. Central Astronomical Observatory at Pulkovo of the Russian Academy of Sciences, St. Petersburg, 196140, Russia

    Yu. Nagovitsyn

Authors
  1. K. Georgieva
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. A. Kilçik
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Yu. Nagovitsyn
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. B. Kirov
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to K. Georgieva.

Additional information

The article is published in the original.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Georgieva, K., Kilçik, A., Nagovitsyn, Y. et al. The Ratio Between the Number of Sunspot and the Number of Sunspot Groups. Geomagn. Aeron. 57, 776–782 (2017). https://doi.org/10.1134/S001679321707009X

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1134/S001679321707009X

Search

Navigation