Earth has experienced ice ages in the past, with large parts of the planet covered in ice for thousands of years.

Over millions of years, Earth’s climate has swung between warm periods and ice ages. During ice ages, huge ice sheets covered large parts of North America, Europe, and Asia. These cold periods were caused by changes in Earth’s orbit, volcanic activity, and other natural factors. Ice ages made life difficult and forced plants and animals to adapt or move. Scientists study ice cores and rocks to understand these past changes and predict future possibilities.