Ice Age

The Ice Ages started 2.4 million years ago and ended 11,500 years ago. The earth’s climate went through cycles of extreme cold and warm periods, with glaciers forming during the cold periods and melting during the warm periods. These cold periods are known as glacials, while the warm periods are called interglacials.

Ice age map of northern Germany

How Much of the Earth Was Covered by Ice?

Scientists believe that about one-third of the Earth was once covered by ice, with some ice sheets reaching a thickness of over a mile. New York is said to have been covered by ice that was more than 1,000 feet thick.

Why Did the Ice Age Happen?

The Ice Age occurred due to temperature changes on Earth. These changes caused various effects, including the formation of the Ice Age. Some theories suggest that the Earth’s position, the angle of sunlight, and changes in the Earth’s tilt led to shifts in weather patterns and ocean currents, ultimately resulting in the Ice Age.


How Do People Know About the Ice Age?

Studying the Earth reveals unique knowledge about our world. By examining fossils and chemicals in rocks, scientists uncover evidence of past events, such as the Ice Age in Northern Europe and North America. These discoveries suggest the existence of massive ice formations and glaciers.


Quaternary Ice Age

Some scientists believe that we are currently in the Quaternary Ice Age, which is a period where the Earth is warmer than earlier stages of the Ice Age but colder than warmer periods. This is also known as the interglacial period.

Interglacial Period

Scientists believe that the Ice Age consists of various parts, with the interglacial period being a warmer phase where glaciers shrink or disappear completely.

Glacial Period

During the Glacial Period, the Earth becomes colder and glaciers grow or form.

What Are the Different Ice Ages?

Scientists have identified five ice ages in the past millions of years and 11 ice ages in the past 4.6 billion years, including Huronian, Cryogenian, Andean-Saharan, Karoo, and Quaternary.


The Huronian ice age occurred due to volcanic activity and lower levels of carbon dioxide in the atmosphere, lasting over 2.1 billion years ago. It is recognized as one of the longest ice ages in history.


The ice age occurred over 635 million years ago and covered the entire world, including areas near the equator.


This ice age was more than 430 million years ago.


The Karoo ice age lasted over 100 million years and is famous for its numerous glacial tills in South Africa, hence its name.


Our current ice age began over 2 million years ago and continues to this day.


During the ice age, glaciers formed and covered waterways and land areas. The freezing and melting of ice contributed to the prolonged duration of the ice age.

What Happened When the Ice Age Ended?

As the Ice Age came to an end, the melting ice shaped rivers, lakes, and streams, while also leaving behind various rocks and debris as the glaciers traversed the land.

Why Do Ice Ages Happen?

Different changes to the Earth can lead to various outcomes, including the formation of ice ages. Scientists attribute the occurrence of ice ages to changes in climate, although there are differing opinions on other potential causes.


Volcanic activity releases gases into the atmosphere, potentially affecting climate patterns. Some argue that a decrease in volcanic activity could contribute to the end of an ice age, while an increase in volcanic activity could lead to more ice ages occurring.


The Earth’s orbit affects its distance from the sun, resulting in variations in temperature. When the Earth is closer to the sun, it becomes hotter, whereas when it is further away, it becomes cooler.


Lower levels of gas in the atmosphere can lead to a cooling effect on Earth, potentially triggering an ice age.


When the sun has less energy, it causes the Earth to be cooler and this can cause an ice age.

Ocean currents

The ocean currents have a significant impact on Earth’s climate. Changes in these currents can lead to the formation of ice.

Continental drift

As different landmasses move, it causes them to move to places in the planet that are colder.


The Earth’s axis can change the way that it tilts and it can cause the Earth to not be facing the sun as it should be.

Animals of the Ice Ages

There are many different animals that lived in the Ice Ages and these include:

  • Wooly Mammoth
  • Cave Bears
  • Wooly Rhino
  • Saber-toothed Tigers
  • Syndoceras
  • Titanotylopus
  • Baluchitherium
  • Brontotherium
  • Teratorn
  • Dire Wolf
  • Giant Beaver
  • Giant Ground Sloth
  • Irish Elk
  • Musk Ox
  • Giant Bison
  • Gylptodon

Animals that lived during the Ice Ages have become extinct. This means that they all died off and they no longer exist.

How Do We Know These Animals Existed?

Scientists and paleontologists have discovered fossils that prove the existence of these animals during the Ice Ages.

People of the Ice Ages

People lived in the Ice Ages and hunted animals for survival, using all parts of the animal for various purposes such as food, clothing, shelter, and weapons.


During the Ice Ages, the Earth was mostly covered in tundra, a cold biome with minimal vegetation. The extreme cold and frozen ground make it difficult for plants and trees to survive in this environment.

There are still some tundra biomes that exist today in places such as:

  • Europe
  • Asia
  • North America

What Did You Learn?

What are the Ice Ages?

The Ice Ages is a period of time where much of the Earth, even 1/3 of it, was covered in ice.

What caused the Ice Ages to happen?

Scientists believe that different things can cause the Ice Age to happen such as the way the Earth rotates, the way the Earth sits on its axis, temperature change, ocean currents, and more.

Did animals live during the Ice Ages?

There is proof that many different animals lived during the Ice Ages. People lived during the Ice Ages too!

What caused the Ice Age to end?

The Ice Age ended when the temperature got warmer. When this happened, the ice began to melt, and oceans and lakes formed all over the world.

Are we in an Ice Age now?

According to scientists, we are still in an ice age, just a warmer ice age than the “Great Ice Age” period.

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