论文标题
部分可观测时空混沌系统的无模型预测
Toroidal flux loss due to flux emergence explains why solar cycles rise differently but decay in a similar way
论文作者
论文摘要
太阳周期的一个惊人特征是，在开始时，黑子出现在中期左右，随着时间的流逝，出现的纬度向赤道迁移。最大的活动水平（例如，日周期）因周期到周期而变化。由于强大的自行车，活动的早期和较高的日子分布比较高的日子越来越弱，而对于较高的日子而言。当皮带仍处于高纬度时，黑子皮带的活性和宽度迅速增加，并开始下降。令人惊讶的是，据报道，在周期的晚期阶段，活动水平（黑子数）以及蝴蝶翅膀的宽度和中心都具有相同的统计属性如果在对流区的下部，在$ 10^4 $ g g的平均范围强度下，非线性的出现在平均范围的强度上有效，则非线性是有效的。
A striking feature of the solar cycle is that at the beginning, sunspots appear around mid-latitudes, and over time the latitudes of emergences migrate towards the equator.The maximum level of activity (e.g., sunspot number) varies from cycle to cycle.For strong cycles, the activity begins early and at higher latitudes with wider sunspot distributions than for weak cycles. The activity and the width of sunspot belts increase rapidly and begin to decline when the belts are still at high latitudes. Surprisingly, it has been reported that in the late stages of the cycle the level of activity (sunspot number) as well as the widths and centers of the butterfly wings all have the same statistical properties independent of how strong the cycle was during its rise and maximum phases.We have modeled these features using a Babcock--Leighton type dynamo model and show that the flux loss through magnetic buoyancy is an essential nonlinearity in the solar dynamo.Our study shows that the nonlinearity is effective if the flux emergence becomes efficient at the mean-field strength of the order of $10^4$~G in the lower part of the convection zone.
