Caption: Yearly average number of sunspots since 1610.

EVERYTHING USEFUL HERE HAS BEEN HARVESTED FOR THE UPDATE

Note the Maunder Minimum. This is the period approximately 1645--1715 where there were few sunspots. The Maunder Minimum time seems to have corresponded to a particularly cold world-wide cold spell beginning about 1650 which in turn was part of a longer world-wide cold spell called the Little Ice Age (see Wikipedia: Little Ice Age). There may be a connection, but we don't know what it is (see Wikipedia: Little Ice Age: Solar activity).

By the by, the Little Ice Age is an ill-defined term. Some people use it for the period approixmately 1350--1850 and mean a period of constant climate shifts and NOT necessarily a cold spell (Fa-248--249).

Credit/Permission: NASA circa or before 2003 / Public domain.
Download site: NASA: sunspots.htm. Alas, a dead link.
Image link: Itself.
Local file: local link: sunspots_solar_cycle_old.html.
File: Sun file: sunspots_solar_cycle_old.html.