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Heartbeat of the Sun from principal component analysis and prediction of solar activity on a millenium timescale

Zharkova, V. V.; Shepherd, S. J.; Popova, E.; Zharkov, S. I.


V. V. Zharkova

S. J. Shepherd

E. Popova


We derive two principal components (PCs) of temporal magnetic field variations over the solar cycles 21–24 from full disk magnetograms covering about 39% of data variance, with σ = 0.67. These PCs are attributed to two main magnetic waves travelling from the opposite hemispheres with close frequencies and increasing phase shift. Using symbolic regeression analysis we also derive mathematical formulae for these waves and calculate their summary curve which we show is linked to solar activity index. Extrapolation of the PCs backward for 800 years reveals the two 350-year grand cycles superimposed on 22 year-cycles with the features showing a remarkable resemblance to sunspot activity reported in the past including the Maunder and Dalton minimum. The summary curve calculated for the next millennium predicts further three grand cycles with the closest grand minimum occurring in the forthcoming cycles 26–27 with the two magnetic field waves separating into the opposite hemispheres leading to strongly reduced solar activity. These grand cycle variations are probed by α − Ω dynamo model with meridional circulation. Dynamo waves are found generated with close frequencies whose interaction leads to beating effects responsible for the grand cycles (350–400 years) superimposed on a standard 22 year cycle. This approach opens a new era in investigation and confident prediction of solar activity on a millenium timescale.


Zharkova, V. V., Shepherd, S. J., Popova, E., & Zharkov, S. I. (2015). Heartbeat of the Sun from principal component analysis and prediction of solar activity on a millenium timescale. Scientific reports, 5(1), Article ARTN 15689.

Journal Article Type Article
Acceptance Date Sep 25, 2015
Online Publication Date Oct 29, 2015
Publication Date Oct 29, 2015
Deposit Date Jul 19, 2016
Publicly Available Date Jul 19, 2016
Journal Scientific reports
Print ISSN 2045-2322
Electronic ISSN 2045-2322
Publisher Nature Publishing Group
Peer Reviewed Peer Reviewed
Volume 5
Issue 1
Article Number ARTN 15689
Keywords Computational astrophysics; Solar physics
Public URL
Publisher URL
Additional Information This is a copy of an open access article published in Scientific reports, 2015, v.5


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