Ice core facts for kids

An ice core is like a long, frozen diary from the past! It's a deep piece of ice that scientists drill out of glaciers. These special ice samples often come from places like Antarctica, Greenland, or very high mountains. By studying them, we can learn amazing things about Earth's history.

A bit of an ice core showing the layers that form every year

What are Ice Cores?

Ice cores are long cylinders of ice. They are drilled from very deep inside glaciers. This allows scientists to reach ice that is thousands of years old. The deeper the ice, the older it is.

How Ice Cores Form

It all starts with snow. Snow falls and builds up over many years. As more snow piles on top, the layers below get squished. This pressure turns the snow into dense firn, and then into solid ice. All the air gets squeezed out.

Scientists can often tell how old the ice is by looking at its layers. Just like tree rings, each year or even each season can form a distinct layer. Sometimes, it's harder to see these layers. In those cases, scientists use other methods. They might measure how well the ice conducts electricity (its conductivity). They also use mathematical models to figure out the age.

Reading the Ice: What We Learn

Scientists study ice cores to find out what the climate was like in the past. The ice traps tiny bits of information. This includes gases, tiny particles, and even ash from volcanoes.

The type of water that makes up the ice can tell us about past temperatures. By looking at different forms of water molecules, scientists can calculate how warm or cold Earth was long ago.

Why Ice Cores Matter

Ice cores help us understand Earth's temperature history. We can learn about the planet's climate over the past 800,000 years! This helps us know more about ice ages, which happen regularly.

This knowledge is very helpful for understanding global warming today. By seeing how climate changed naturally in the past, we can better understand current changes.

Images for kids

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  Ice core sample taken from drill

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  Sampling the surface of Taku Glacier in Alaska.

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  An ice auger patented in 1932. Modern augers for shallow drilling look very similar.

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  Sawing the GRIP core

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  Ozone-depleting gases found in Greenland firn.

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  36Cl from 1960s nuclear testing found in US glacier ice.

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  A store of core samples

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  Data showing CO2 levels and related ice ages over nearly 800,000 years.

See also

In Spanish: Testigo de hielo para niños