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Belyaev Yu. R. Panin A. V. Kiryuhina A. D. Koshurnikov A. V. Kramynin A. M. Pavlov M. A. Konstantinov E. A. Kurbanov R. N. Zakharov A. L. Sychev N. V. 《Doklady Earth Sciences》2022,506(1):S84-S93
Doklady Earth Sciences - A complex of works including geomorphological deciphering, field survey, drilling, electric prospecting, and dating of deposits using the radiocarbon method and optically... 相似文献
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Long-term changes in the magnetic activity of the Sun were studied in terms of the empirical mode decomposition that revealed
their essential modes. The occurrence of grand minima was also studied in their relation to long-term changes in sunspot activity
throughout the past 11 000 yr. Characteristic timescales of long-term changes in solar activity manifest themselves in the
occurrence of grand minima. A quantitative criterion has been defined to identify epochs of grand minima. This criterion reveals
the important role of secular and bicentennial activity variations in the occurrence of grand minima and relates their amplitudes
with the current activity level, which is variable on a millennial timescale. We have revealed specific patterns in the magnetic
activity between successive grand minima which tend to recur approximately every 2300 yr but occasionally alternate with irregular
changes. Such intermittent activity behavior indicates low dimensional chaos in the solar dynamo due to the interplay of its
dominant modes. The analysis showed that in order to forecast activity level in forthcoming cycles, one should take into account
long-term changes in sunspot activity on a ≈2300-yr timescale. The regularities revealed suggest solar activity to decrease
in the foreseeable future. 相似文献
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It is shown that “active longitudes” for the sunspots of old and new cycles manifest themselves approximately in the same longitudinal intervals and remain for several 11-year cycles. To be more accurate, they vanish in some cycles but then appear again at the same longitudinal intervals in the other cycles. The entire period is characterized by a total of four active longitudes. The old-cycle sunspots observed at low equatorial latitudes in the Northern and Southern Hemispheres are characterized by a shift by ≈180°, which indicates antipodality of the active longitudes in the Northern and Southern Hemispheres. In the case of highlatitude sunspots (new-cycle sunspots), the best correlation is observed for the shift of ≈90°. There is supposedly a dependence of the rotation speed of active longitudes on the secular cycle. 相似文献
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Geomagnetism and Aeronomy - In this article, the dynamics of the annual variation in the mean monthly values of temperature and precipitation is studied via the expansion of series into natural... 相似文献
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Geomagnetism and Aeronomy - The characteristics of the latitude-longitude distribution of the north–south (NS) asymmetry of the number of sunspots for the period of 1874–2013 are... 相似文献
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Long-term variations in solar activity secular cycles have been studied using a method for the expansion of reconstructed sunspot number series Sn(t) for 11400 years in terms of natural orthogonal functions. It has been established that three expansion components describe more than 98% of all Sn(t) variations. In this case, the contribution of the first expansion component is about 92%. The averaged form of the 88year secular cycle has been determined based on the form of the first expansion coordinate function. The quasi-periodicities modulating the secular cycle have been revealed based on the time function conjugate to the first function. The quasi-periodicities modulating the secular cycle coincide with those observed in the Sn(t) series spectrum. A change in the secular cycle form and the time variations in this form are described by the second and third expansion components, the contributions of which are about 4 and 2%, respectively. The variations in the steepness of the secular cycle branches are more pronounced in the 200-year cycle, and the secular cycle amplitude varies more evidently in the 2300-year cycle. 相似文献
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