除左個體嘅壽命,太陽黑子整體上亦有周期嘅,我地叫做Sunspot Cycle 黑子週期。
Climate model simulations suggest multiple factors, particularly volcanic activity, were crucial for causing the cooler temperatures in the northern hemisphere during the LIA. A reduction in total solar irradiance likely contributed to the LIA at a level comparable to changing land use [by humans].