当太阳内部深处形成巨大的磁力环，该处将会产生井喷并突破太阳表面，从而使表面的局部地区温度下降，看上去就像一个暗斑，这就是黑子的形成。

They form where giant loops of magnetism, generated deep inside the sun, well up and burst through the surface, leading to a localised drop in temperature which we see as a dark patch.

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局域波分析方法的重大突破在于用基于信号局部特征的多个基本模式分量来描述信号，并赋予每个基本模式分量具有实际物理意义的瞬时频率。

The main innovations embodied in this method are the introduction of the intrinsic mode functions based on local properties of signals, which make the instantaneous frequency meaningful.

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