Space Science Reviews

, Volume 94, Issue 1–2, pp 139–144 | Cite as

Modelling Short-Term Spectral Irradiance Variations

  • M. Fligge
  • S.K. Solanki
  • Y.C. Unruh


On time-scales of the solar rotation most of the solar irradiance variations are caused by the changing distribution of solar surface magnetic features. We model these short-term irradiance variations using calculations of sunspot and facular contrasts as a function of wavelength and limb angle on the Sun. The position of active regions on the solar disc is derived from the MDI magnetograms. The reconstructed irradiance variations are compared with total and spectral irradiance measurements obtained by the VIRGO experiment on SOHO.


Active Region Solar Irradiance Magnetic Feature Solar Disc Solar Surface 
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Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • M. Fligge
    • 1
  • S.K. Solanki
    • 1
  • Y.C. Unruh
    • 2
  1. 1.Institute of AstronomyETH ZentrumZurichSwitzerland
  2. 2.Institut für AstronomieUniversität WienWienAustria

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