Excerpts from Harris Mann
Global Temperature Trends From 2500 B.C. To 2008 A.D.
From August of 2007 through February of 2008, the Earth’s mean reading dropped to near the 200-year average temperature of 57 degrees.
Our recent decline in the Earth’s temperature may be a combination of both long-term and short-term climate cycles, decreased solar activity and the development of a strong long-lasting La Nina, the current cooler than normal sea-surface temperature event in the south-central Pacific Ocean. Sunspot activity in the past 18 months has decreased to the lowest levels since ‘The Little Ice Age’ ended in the mid-to late 1800s. This "cool spell," though, may only be a brief interruption to the Earth’s overall warming trend. Only time will tell.
By the end of this 21st Century, a big cool down may occur that could ultimately lead to expanding glaciers worldwide, even in the mid-latitudes. We could possibly see even a new Great Ice Age. Based on long-term climatic data, these major ice ages have recurred about every 11,500 years. Well, you guessed it. The last extensive ice age was approximately 11,500 years ago, so we may be due.