Solar activity fluctuates in an 11-year cycle. But so far in this cycle, the sun has been disturbingly quiet. The lack of increased activity could signal the beginning of what is known as a Maunder Minimum, an event which occurs every couple of centuries and can last as long as a century.
Such an event occurred in the 17th century. The observation of sunspots showed extraordinarily low levels of magnetism on the sun, with little or no 11-year cycle.
This solar hibernation corresponded with a period of bitter cold that began around 1650 and lasted, with intermittent spikes of warming, until 1715. Frigid winters and cold summers during that period led to massive crop failures, famine and death in Northern Europe.
Tapping reports no change in the sun's magnetic field so far this cycle and warns that if the sun remains quiet for another year or two, it may indicate a repeat of that period of drastic cooling of the Earth, bringing massive snowfall and severe weather to the Northern Hemisphere.
Scientists want to do more research on this phenomenon.