What do Antarctic ice cores tell us about climate change?

Summary

Ice cores preserve evidence of past climate, helping scientists understand how Earth’s climate has changed and may change in the future. Ice-core scientist Nerilie Abram describes working at remote Antarctic field sites, where teams must build and run their own camps.

Scientific Concepts and Methods

• A winch lowers a drill into the ice. Scientists drill about 1.5 metres at a time, bring each section to the surface, and repeat the process down through the ice sheet.
• Deeper ice formed earlier in history. One 364-metre core contained ice more than 20,000 years old at its base.
• In the part of Antarctica Abram discusses, temperatures have risen by more than 2°C in 50 years. Glaciers are flowing faster, and ice shelves are collapsing.
• Tiny bubbles trapped in ice preserve samples of the ancient atmosphere. Measuring greenhouse gases in these bubbles helps scientists compare past atmospheric composition with past temperatures and better understand climate change.

Researchers and Sources Featured

• Nerilie Abram, ice-core scientist
• British Antarctic Survey, Abram’s research organization