Ice age
A cold period in Earth history when large ice sheets extend from the polar regions into temperate latitudes. The term is sometimes used synonymously with "glacial period" or "glacial period", or embraces several such periods to define a major phase of cold climate in Earth’s climatic history.
 |
During the last ice age the Laurentide ice sheet of North America extended as far south as New York. Photo J. Alean. |