What’s In This 20,000 Year-Old Ice Cube?

Scientists are studying air bubbles trapped in ice from 20,000 years ago and comparing it to what we breathe today. What can ancient ice cores teach us about climate change?

The climate on Earth has changed through the millennia. How can we know that this time climate change has happened because of humans? Scientists are studying ice they have excavated from Antarctica to find out what was in the air 20,000 years ago.

They do this through a process that isolates tiny air deposits trapped in ice from long ago. These air pockets have different gases within them, and those gases and their concentrations tell the scientists about the warming nature of our climate today and one key clue that tells them that this time humans are to blame.