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Depiction of the asteroid that struck Earth 65 million years ago near the Yucatan Peninsula.

Don Davis, NASA

 Snowball Earth

 Thermal Maximums

 Cataclysmic Events


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Antarctic Ice: An 800,000 Year Record of Climate Change Last Updated on 2009-08-19 00:00:00 Antarctic Ice: An 800,000 Year Record of Climate Change provides an extraordinary opportunity for scientists to reconstruct climate events of the past. Scientists have recently been able to assemble a continuous 800,000 year record of climate change using ice core samples from Antarctica.  This record not only contains information relevant to global temperature changes but also contiguous information on tends of atmospheric greenhouse concentrations during the same period.  Other scientific sources of information exist that shed light on ancient Earth climate conditions, known as paleoclimate, at various times throughout the 4.5 billion year history of the planet.  But the importance of the Antarctic ice record is that it provides a continuous and fairly fine resolution record of climate cycles throughout the entire period of existence of our species, Homo sapiens,... More »