DENVER– A huge federal government freezer west of Denver holds the nation’s collection of ice cores crucial for analyzing climate change.

The ice cores come from Antarctica, Greenland and Alaska. In order to keep them from melting, curators keep the freezer set at around at least as cold as minus 11 degrees Fahrenheit. They have backup generators in case the power goes out.

This National Ice Core Laboratory contains a total ice coming from 80 different samples.

Scientific research crews drill new cores every year.

First crews fly a C130 plane from McMurdo Station in Antarctica to the drilling sites across the ice sheet. They sleep in tents buffeted by fierce winds and use special drilling machinery to drill ice cores from deep underground. They do this during summer. They fly the ice cores back to the McMurdo Station. They load those frozen cores onto a ship that carries them to California. From California, crews load the ice into a truck which hauls them to the freezer west of Denver.

Why is it critical to study these ice cores? Is it really worth all this effort?

Ice cores are indeed the most accurate source of data telling us the history of the Earth’s climate for the past 850,000 years. It is also one of the best sources of knowledge to analyze climate change- and try to anticipate what may happen in the next 100 years.

Some ancient ice contains an ash layer, from past volcanic eruptions. The deeper researchers drill into the ice, the tighter the ice is, and less air is trapped. The ice near the bed rock is completely solid with no trapped air, said Richard Nunn, a scientist at the lab.

Ice cores hold gases such as argon, ethane, methane and carbon dioxide. By testing the gases trapped in the cores, scientists essentially can look back in time to understand the air temperature and air chemistry from another time.

Through studying ice cores, the grand majority of scientists have concluded that climate change is increasing at an exponential rate.

Standing outside the lab, Nunn, proposed two ways to slow the effects of climate change. One, convince skeptical politicians to investigate the science behind the earth’s climate. Second, people should pollute less, Nunn said. “Anything helps.”