The cycle begins with a concentrated ring of convection that develops outside the eye wall . the ring of convection then propagates inward leading to a double - eye 周期开始时一个环型的密集对流区首先在眼壁外发展，继而向内移动，以至出现双重眼壁结构。
2.
The cycle begins with a concentrated ring of convection that develops outside the eye wall . the ring of convection then propagates inward leading to a double - eye 周期开始时一个环型的密集对流区首先在眼壁外发展，继而向内移动，以至出现双重眼壁结构。
