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Solar activity behaviour on the eve of the Maunder minimum may provide important information on the period of further suppression of sunspot population. We analyse sunspot positions and areas in the 1630s extracted from rare drawings published by Pierre Gassendi in Opera Omnia. This work was published in two different editions, the first in Lyon and the second almost 70 years later in Florence. The drawings published in Lyon are found to be slightly different from those published in Florence, which produces a discrepancy in the position of spots of a few degrees, while sunspot group areas may differ by a factor of two. We reveal that the orientation of the drawings in the book is not always the same as might be seen in the telescope. We conjecture that the time of Gassendi’s observations covers the beginning of a new Schwabe cycle in the southern hemisphere. The differential rotation rate in the 1630s is also assessed and discussed. 相似文献
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Historical sunspot records were analyzed by means of nonlinear tools to find synchronization phenomena at different time scales
on the Sun. Using cross-recurrence plots it is shown that the north – south sunspot synchronization demonstrates a set of
distinct periodic oscillations – 43.29, 18.52, and 7.63 years. Also we have traced the sunspot synchronization on shorter
time scales. Very rare and episodic synchronization within half of the Carrington rotation rate was detected. By using the
empirical mode decomposition technique the north – south sunspot time series were decomposed into intrinsic oscillatory modes.
To determine which modes of the signal are responsible for synchronization we separated them into high- and low-frequency
parts. It is shown that phase synchronization is detected only in the low-frequency modes. The high-frequency component demonstrates
noisy behavior with amplitude synchronization and strong phase mixing. 相似文献
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Geomagnetism and Aeronomy - The shift of the heliospheric current sheet (HCS) can be judged by the correlation between polarities of the interplanetary magnetic field (IMF) observed near the Earth.... 相似文献
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Gnevyshev’s hypothesis of time space organization of sunspot activity over the solar surface like impulses is considered. Using numerical simulation it was shown that complex solar cycle shape can be explained by distribution of impulses in the northern and southern hemispheres. For long solar cycles, impulses at higher latitudes breaking Sp?rer’s law were found. Comparison of the time-latitude diagrams of solar magnetic fields and impulses has shown that each wave of new polarity to the poles is accompanied by impulse of sunspot activity. 相似文献
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One of the most enigmatic features of the solar history is the Maunder minimum (1645–1715). We compare the scatter of amplitudes of the 11-year cycles, according to the new Sunspot Number and Sunspot Group series version 2.0, along with scenario of the Maunder minimum as a period with non-stopped cyclicity. We demonstrate that both amplitude and duration of cycles after the Gleissberg and Maunder minima are similar. Moreover, times of minima and maxima of cycles in the course the Maunder minimum coincide with those during the Gleissberg one, indicating a secular variation. Usefulness of the proxy data within the Maunder minimum is discussed. The scatter of amplitudes and duration of the Schwabe cycles in the past is argued to be comparable with those in the modern epoch. 相似文献
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The spatiotemporal organization of sunspots in the form of activity impulses (according to Gnevyshev’s terminology) is considered as a source of poleward magnetic surges of new polarity. Polar fields in the northern and southern hemispheres have been reconstructed from 1875 to 2012. An increase in the tilt angle of magnetic bipoles with latitude is a crucial parameter in the proposed model to reverse the polar field on the Sun. The role of the surface meridional flow forming magnetic surges of new and old polarities is discussed. It is shown that the velocity and the latitudinal profile of the flow influence the modeled polar field. 相似文献
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