Ice Cores

The cold never bothered our USGS scientists! They ask – do you want to collect an ice core?

Analyzing ice cores is a lot like stepping into a time machine. Each year, snow falls on polar ice sheets and mountain glaciers. As the layers accumulate and solidify into ice, tiny air bubbles and debris get trapped. The ice gets thicker and thicker, in some places as much as several kilometers thick! Scientists drill ice cores to study changes in temperature, precipitation, and volcanic and fire activity going back up to 800,000 years in the past.

Each layer of ice tells a story. For instance, a darker layer can indicate soot from a major wildfire in the past, and tiny air bubbles trapped in the ice can be sampled to learn the exact chemical makeup of the air thousands of years ago.

Graphic by: Ben Slyngstad, USGS ORISE