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arXiv · 1201.0819

Why isn't the solar constant a constant?

K. J. Li·W. Feng·J. C. Xu·P. X. Gao·L. H. Yang·H. F. Liang·L. S. Zhan
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Abstract

In order to probe the mechanism of variations of the Solar Constant on the inter-solar-cycle scale, total solar irradiance (TSI, the so-called Solar Constant) in the time interval of 7 November 1978 to 20 September 2010 is decomposed into three components through the empirical mode decomposition and time-frequency analyses. The first component is the rotation signal, counting up to 42.31% of the total variation of TSI, which is understood to be mainly caused by large magnetic structures, including sunspot groups. The second is an annual-variation signal, counting up to 15.17% of the total variation, the origin of which is not known at this point in time. Finally, the third is the inter-solar-cycle signal, counting up to 42.52%, which are inferred to be caused by the network magnetic elements in quiet regions, whose magnetic flux ranges from $(4.27-38.01)\times10^{19}$ Mx.

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K. J. Li, W. Feng, J. C. Xu, P. X. Gao, L. H. Yang, H. F. Liang, L. S. Zhan. 2012-01-04. Why isn't the solar constant a constant?. https://doi.org/10.1088/0004-637x/747/2/135

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