GEOLOGY

Detailed explanation-1: -Examining the gasses trapped in ice cores is how scientists first learned that the amount of carbon dioxide and the global temperature have been linked at least the last million years of Earth’s history.

Detailed explanation-2: -These air pocket “fossils” provide samples of what the atmosphere was like when that layer of ice formed, LeGrande said. “Scientists can directly measure the amount of greenhouse gases that were in the atmosphere at that time by sampling these bubbles, ” she added.

Detailed explanation-3: -By looking at past concentrations of greenhouse gasses in layers in ice cores, scientists can calculate how modern amounts of carbon dioxide and methane compare to those of the past, and, essentially, compare past concentrations of greenhouse gasses to temperature.

Detailed explanation-4: -The bubbles trapped in the ice can even tell us what the air was like at the time the ice was first formed, helping us to measure the changing levels of greenhouse gases in the atmosphere.

Detailed explanation-5: -By drilling down to a particular layer, the oxygen isotopes in a core sample’s air bubbles will tell you the global temperature for the time that the air was trapped in snowflakes. This temperature can then be compared with the air’s carbon dioxide content.