According to the best scientific minds, the earth is 4.54 ± 0.05 billion years old. And since its beginning, the earth has experienced at least five major ice ages, i.e. the Huronian, Cryogenian, Andean-Saharan, Karoo Ice Age and the current Quaternary. In between ice ages, the earth appears to have been ice free -- even in high latitudes. "Ice age" is a term that implies the presence of extensive ice sheets in the northern and southern hemispheres. By this definition, we are still in the ice age that began 2.6 million years ago because the Greenland, Arctic, and Antarctic ice sheets still exist. Therefore, the earth is still warming up from the most recent ice age -- and is expected to continue to warm until it is ice free. There has been no satisfactory theory presented to explain earth's ice age history. The cause of an ice age is believed to be related to several simultaneously occurring ice-age-factors, i.e. astronomical cycles, atmospheric composition, plate tectonics, and/or...(Read Full Post)