What if there was a way to compare a sample of Earth’s atmosphere today with one from 800,000 years ago? That kind of information could be invaluable to researchers studying climate change, and thanks to a fascinating technique being used at the University of Washington, it's a reality.

Each year several researchers from UW travel to far flung places across the globe to harvest ancient samples of our atmosphere from Earth's ice sheets.

The best samples come from the oldest and most difficult ice to reach, making Greenland and Antarctica excellent storehouses of ancient atmosphere. When the snow fell to create what are today’s ice sheets, the crystals of snow encased small samples of the atmosphere at the time, according to UW postdoctoral research associate Peter Neff.

Pieces of the Earth's ancient atmosphere are trapped in air bubbles in ice harvested from Greenland.

Today, researchers are able to extract those tiny bubbles of air by coring deep into the ice sheet.

Once brought back to the lab, a better understanding of the composition of the atmosphere from that time period helps piece together the puzzle of how Earth’s atmosphere has changed over time.

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