Glacial period — Safekipedia Discoverer

A glacial period (also called a glacial or glaciation) is a time lasting thousands of years when Earth gets much colder and glaciers grow larger. These colder periods happen inside longer times called ice ages. Between these cold times, Earth warms up again in periods called interglacials. The most recent big cold time, called the Last Glacial Period, ended around 15,000 years ago. Today we live in a warm time called the Holocene, which is an interglacial. When there are no glaciers anywhere on Earth, scientists call this a greenhouse climate state. During glacial periods, huge sheets of ice cover many parts of the land, changing rivers, mountains, and even the shape of the continents. These changes affect where plants and animals can live and help shape the world we see today.

Quaternary Period

Glacial and interglacial cycles as represented by atmospheric CO2, measured from ice core samples going back 800,000 years. The stage names are part of the North American and the European Alpine subdivisions. The correlation between both subdivisions is tentative.

Main articles: Quaternary glaciation and Timeline of glaciation

The Quaternary period, which began about 2.6 million years ago, has seen many glacial periods and warmer times called interglacials. During these glacial periods, Earth’s climate grew much colder, and glaciers expanded. These changes were largely driven by shifts in the amount of carbon dioxide in the atmosphere. Over the last 740,000 years, there have been at least eight such glacial cycles.

Penultimate Glacial Period

Main article: Penultimate Glacial Period

The Penultimate Glacial Period is the time of cold weather and growing glaciers that happened before the Last Glacial Period. It started about 194,000 years ago and ended about 135,000 years ago, when a warmer time called the Eemian began.

Last Glacial Period

Main article: Last Glacial Period

The Last Glacial Period was the most recent time when large glaciers covered many parts of the Earth. It began about 110,000 years ago and ended around 11,700 years ago. During this time, ice covered much of the Northern Hemisphere, with different names for the glaciers depending on where they were, such as Wisconsin in North America and Weichsel in northern Central Europe. The biggest expansion of ice happened about 26,500 years ago, reaching as far as Northern Germany. Over the past 650,000 years, Earth has experienced many cycles of glaciers growing and then shrinking.

Next glacial period

Because the way Earth's orbit changes can be predicted, scientists can use computer models to guess what the climate might be like in the future. Some research suggests that our current warm period could continue for about another 50,000 years. However, the large amount of heat-trapping gases we are adding to the atmosphere and oceans might push the start of the next glacial period even further into the future, possibly adding another 50,000 years to the timeline.