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| Titel |
Prediction of solar cycle 24 based on the Gnevyshev-Ohl-Kopecky rule and the three-cycle periodicity scheme |
| VerfasserIn |
R. P. Kane |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
0992-7689
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| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 26, no. 11 ; Nr. 26, no. 11 (2008-10-21), S.3329-3339 |
| Datensatznummer |
250016274
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| Publikation (Nr.) |
 copernicus.org/angeo-26-3329-2008.pdf |
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| Zusammenfassung |
An examination of the maximum yearly values of the
conventional sunspot number Rz of all cycles revealed fluctuations of various
intervals in the high periodicity region (exceeding 11 years), namely 2
cycles (Hale, 22 years), 3 cycles (TRC, three-cycle) and longer intervals. The
2-cycle spacings had the smallest amplitudes. According to the G-O
(Gnevyshev-Ohl) rule (Gnevyshev and Ohl, 1948), the even-numbered series of
the maxima of annual mean Wolf sunspot numbers Rz are followed by higher
amplitude odd-numbered series. Kopecky (1950) generalized this relation
to annual mean Wolf numbers corresponding to equivalent phases of the
adjacent even-odd 11-year cycles. Therefore, we would call it the G-O-K rule. For the
data of 28 cycles (cycle −4 to cycle 23), it was found that four pairs (~29%)
from the fourteen even-odd pairs showed failure of the G-O-K rule. In the remaining ten pairs, the magnitudes of the odd cycles
were well-correlated with the magnitudes of the preceding even cycles, but
it was impossible to tell whether it would be a normal pair following the
G-O-K rule or a possible case of failure. A much stronger sequence was the
three-cycle sequence (TRC, low, high, higher). The 2-cycle oscillations were
embedded into the TRC until the G-O-K rule failures occurred as in cycle 23. The
patterns of cycle 17 (low), 18 (high), 19 (higher); 20 (low), 21 (high), 22
(higher) were noticed and used by Ahluwalia (1995, 1998) to predict a low
value for cycle 23, which was accurate. However, in the earlier data, the
preceding sequence (14, 15, 16) was rather uncertain, and before
that for seven cycles (cycles 8-14), there were no TRC sequences at all.
During the twelve cycles −4 to 7, there were only three isolated TRC
sequences (one doubtful).
In view of this chequered history of TRC, it is
doubtful whether the present TRC pattern (cycles 17–23) would persist in
the near future. Spectral analysis showed that in the first half (cycles −4 to
9), larger periodicities (reminiscent of the Gleissberg cycle of ~80
years) prevailed. but in the latter half, periodicities were different
(3-year cycle was predominant) and the matching was not good. In particular,
the points for the recent cycles 21, 22 seemed to deviate considerably from
the constructed series, thus introducing unreliability in predictions for the
future by using extrapolation of periodicities. |
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