Those sunspots I blogged about this morning? All may not be as it seemed.
Sunspot numbers do have an 11 year cycle and we have been in an extended minimum (in numerical count of the sunspots). However, after each minimum, the sunspots themselves are different – they have the opposite magnetic polarity from the previous cycle.
The new spots have the polarity that characterizes them as belonging to the last cycle.
[T]he new sunspots have a magnetic polarity consistent with Solar Cycle 23 rather than the new cycle, proving yet again that much remains to be learned about the temperamental sun.
A solar disk devoid of sunspots for an extended period has happened before. One such period, known as the Maunder Minimum, occurred from 1645 to 1715.
During the coldest part of the Little Ice Age, from 1645 to 1715, there is believed to have been a decrease in the total energy output from the Sun, as indicated by little or no sunspot activity. Known as the Maunder Minimum, astronomers of the time observed only about 50 sunspots for a 30-year period as opposed to a more typical 40-50,000 spots.
The Little Ice Age was a longer period, which lasted from about 1150 until 1850.
During the Little Ice Age, access to Greenland was largely cut off by ice from 1410 to the 1720s. At the same time, canals in Holland routinely froze solid, glaciers advanced in the Alps, and sea-ice increased so much that no open water was present in any direction around Iceland in 1695.
From the graph on the right, you can see how the period of least sun spot activity matches the peak in the price of wheat in different countries (for which there is ample historical record). The price is used as a proxy for the temperature, and is echoed in the prices of other temperature-sensitive commodities.
It may be that Global Cooling is a more realistically a danger than Global Warming. It certainly would be more devastating to the economy of nations and the lives of individuals.