Variations in temperature, CO2, and dust from the Vostok, Antarctica ice core over the last 400,000 years
Rise of temperature at the end of the last ice age
An ice age is a period when for a long time the temperature of Earth's climate is very low. This leads to an expansion of the continental ice sheets, polar ice sheets and mountain glaciers.
'Ice age' is a term used in palaeoclimatology for the period of extensive ice sheets in the recent Pleistocene period. We now know that ice ages have happened a number of times in the past, the greatest and longest of which took place in the Proterozoic era, before multi-cellular eukaryotes evolved.