Think this is just some winter snow and ice behind me?

Think again.

I'm standing in front of a glacier.

My question is how are glaciers formed?

I'm standing in front of Solheimajokull, a glacier in southern Iceland that geologists estimate has been around for 400 to 600 years.

A glacier is a really thick, really dense mass of ice that has formed on land and is slowly moving downwards or outwards, under the force of its own weight and gravity.

Glaciers form over many, many years when snow that falls exceeds the amount of snow that melts.

Over time, that snow builds up and starts to get packed down or compressed under its own weight.

It becomes extremely thick, dense ice with very little air trapped inside.

Glaciers only form on land.

The pieces that break off and slide into the sea are called icebergs.

They used to be part of a glacier.

Have you ever heard the expression you're moving at a glacial pace?

It means really, really slowly, because it often looks like a glacier isn't moving at all.

But nothing could be further from the truth.

Glaciers are constantly moving, spreading outwards or flowing downhill towards the sea.

And while some only move a few centimeters each day, others can move up to 30 meters, about 90 feet.

Sometimes glaciers surge and move even faster for a short amount of time.

Even when they're moving slowly, Glaciers shape our landscape, creating mountains and valleys, craters and lakes.

And glaciers are really important, they hold more than two thirds of all the fresh water on earth.

Over the last hundred years, glaciers around the world have been receding or shrinking.

And that's a big deal.

Because when glaciers melt, that water goes into the ocean, raising sea levels around the globe.

Iceland alone has lost dozens of glaciers.

Researchers and artists in 2024 actually built a glacier graveyard outside of the capital, Reykjavik, to highlight the fact that many more glaciers could go extinct in the years to come because of climate change.

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