Skip to main content

The Wolf number and total solar irradiance variations during 21–23 solar cycles

Buy Article:

$63.00 plus tax (Refund Policy)


In this work, the numerical sequences of the total solar irradiance data and the corresponding values of the international sunspot index, both for the same time interval (about 25 years), are compared. The data are analysed by means of two methods: continuous wavelet transformation and Fourier spectrum decomposition. Special attention is given to short periods of approximately 27 days. It is shown that the 27 day periodicity, caused by rotation of the active regions, is demonstrated well in the Wolf number spectrum, while in the total solar irradiance spectrum a time interval of about 15–60 days is displayed. The peaks at about 1 year and the weaker quasibiennial peaks (2–2.5 years) are noticeable in both spectra.

Keywords: Sun; Total solar irradiance; Wavelet analysis; Wolf numbers

Document Type: Research Article


Affiliations: Sternberg Astronomical Institute, Universitetskij Prospekt 13, Moscow, 119992, Russia

Publication date: 2006-08-01

More about this publication?
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more