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Snowball Earth Period  By Sam All About the Snowball Earth Period The [|Snowball Earth] period was a time when the earth was extremely cold, the oceans were frozen, and glaciers covered most of the contingents. The temperatures on earth were forty degrees below zero. Only algea and bacteria were able to survive these extreme temperatures. This period lasted millions between 590-750 million years ago. media type="custom" key="24250736"

Scientists believe it was so cold that ice even formed near the equator. However, they argued that the planet was likely more "slush" and not completely frozen or the earth would have remained frozen forever.

How The Snowball Earth Period Ended Despite the extreme cold temperatures, the earth was not entirely frozen. Scientists believe that the earth began to thaw as "greenhouse gases" started to accumulate in the atmosphere. Carbon dioxide, which retains heat, is likely the reason why the earth eventually thawed out and melted most of the ice. Scientists agree complex life began on earth following this "snowball" period.

How the Snowball Earth Period Affected the History of the Earth

Sources

http://www.snowballearth.org/what.html

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