This graph image could be re-created using vector graphics as an SVG file. This has several advantages; see Commons:Media for cleanup for more information. If an SVG form of this image is available, please upload it and afterwards replace this template with {{vector version available|new image name}}. It is recommended to name the SVG file “Sunspot Numbers.svg”—then the template Vector version available (or Vva) does not need the new image name parameter.

Sažetak

This figure summarizes sunspot number observations. Since c. 1749, continuous monthly averages^{[dead link]} of sunspot activity have been available and are shown here as reported by the Solar Influences Data Analysis Center, World Data Center for the Sunspot Index, at the Royal Observatory of Belgium. These figures are based on an average of measurements from many different observatories around the world. Prior to 1749, sporadic observations of sunspots are available. These were compiled and placed on consistent monthly framework by Hoyt & Schatten (1998a, 1998b).

The most prominent feature of this graph is the c. 11 year solar magnetic cycle which is associated with the natural waxing and waning of solar activity.

On longer time scales, the sun has shown considerable variability, including the long Maunder Minimum when almost no sunspots were observed, the less severe Dalton Minimum, and increased sunspot activity during the last fifty years, known as the Modern Maximum. The causes for these variations are not well understood, but because sunspots and associated faculae affect the brightness of the sun, solar luminosity is lower during periods of low sunspot activity. It is widely believed that the low solar activity during the Maunder Minimum may be among the principal causes of the chilly Little Ice Age, circa 1350-1850 A.D.

Copyright

This figure was prepared by Robert A. Rohde and is part of the Global Warming Art project.

Image from Global Warming Art

This image is an original work created for Global Warming Art. Please refer to the image description page for more information.

Dozvoljeno je kopirati, distribuirati i/ili mijenjati ovaj članak pod uslovima navedenim u GNU licenci za slobodnu dokumentaciju, verzija 1.2 ili kasnijom verzijom izdatom od Free Software Foundation; bez nepromjenljivih dijelova, te bez sadržaja na naslovnoj i zadnjoj strani. Kopija licence se nalazi pod poglavljem GNU Free Documentation License.http://www.gnu.org/copyleft/fdl.htmlGFDLGNU Free Documentation Licensetruetrue

	Ova datoteka je licencirana pod Creative Commons Attribution-Share Alike 3.0 neportiranom licencom.
	Slobodni ste: da dijelite – da kopirate, distributirate i prenosite djelo da remiksate – da prilagodite djelo Pod sljedećim uslovima: pripisivanje – Morate pripisati odgovarajuće autorske zasluge, osigurati link ka licenci i naznačiti jesu li napravljene izmjene. To možete uraditi na bilo koji razumni način, ali ne tako da se sugerira da davalac licence odobrava Vas ili Vašu upotrebu njegovog djela. dijeli pod istim uslovima – Ako mijenjate, transformišete ili nadograđujete ovaj materijal, morate ga objaviti i distribuirati samo pod istom ili sličnom licencom poput ove.
	Ova oznaka licence je dodana na ovu datoteku kao dio GFDL ažuriranja licence.http://creativecommons.org/licenses/by-sa/3.0/CC BY-SA 3.0Creative Commons Attribution-Share Alike 3.0truetrue

References

• Hoyt, D. V., and K. H. Schatten (1998a). "Group sunspot numbers: A new solar activity reconstruction. Part 1.". Solar Physics 179: 189-219.
• Hoyt, D. V., and K. H. Schatten (1998b). "Group sunspot numbers: A new solar activity reconstruction. Part 2.". Solar Physics 181: 491-512.
• Stott, Peter A.; Gareth S. Jones and John F. B. Mitchell (15 December 2003). "Do Models Underestimate the Solar Contribution to Recent Climate Change". Journal of Climate 16: 4079-4093.