The Solar Cycle is reviewed. The 11-year cycle of solar activity is characterized by the rise and fall in the numbers and surface area of sunspots. We examine a number of other solar activity indicators including the 10.7 cm radio flux, the total solar irradiance, the magnetic field, flares and coronal mass ejections, geomagnetic activity, galactic cosmic ray fluxes, and radioisotopes in tree rings and ice cores that vary in association with the sunspots. We examine the characteristics of individual solar cycles including their maxima and minima, cycle periods and amplitudes, cycle shape, and the nature of active latitudes, hemispheres, and longitudes. We examine long-term variability including the Maunder Minimum, the Gleissberg Cycle, and the Gnevyshev-Ohl Rule. Short-term variability includes the 154-day periodicity, quasi-biennial variations, and double peaked maxima. We conclude with an examination of prediction techniques for the solar cycle.

中文翻译：

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太阳周期

太阳周期被审查。太阳活动的11年周期的特征是黑子的数量和表面积的上升和下降。我们研究了许多其他太阳活动指标，包括10.7厘米的无线电通量，总太阳辐照度，磁场，耀斑和日冕质量抛射，地磁活动，银河系宇宙射线通量以及树木年轮和冰芯中的放射性同位素与黑子的联系。我们研究了单个太阳周期的特征，包括其最大值和最小值，周期和振幅，周期形状以及活动纬度，半球和经度的性质。我们研究了长期的可变性，包括Maunder最小值，Gleissberg周期和Gnevyshev-Ohl规则。短期变化包括154天的周期，准两年期变化，和双峰最大值。最后，我们对太阳周期的预测技术进行了考察。