Hello,

There is a lot of uncertainty in the role of the Sun in global climate change. The 11-year solar cycle is quite well known, but there appears to be longer term variability in solar activity and the Sun's energy output. For example, the "Little Ice Age" recorded in Europe between 1550 and 1700 happened during a time of very low solar activity called the Maunder Minimum. However, even though changes in solar activity appear to have some influence on Earth's climate, the present changes in temperature are thought to be caused primarily by humans and increased output of greenhouse gases. The Stanford Solar Center has a really nice web site about the Sun and global climate change: http://solar-center.stanf...earth/glob-warm.html

Kris