EVERYDAY SCIENCE

Detailed explanation-1: -Over the last 800, 000 years atmospheric CO2 levels as indicated by the ice-core data have fluctuated between 170 and 300 parts per million by volume (ppmv), corresponding with conditions of glacial and interglacial periods.

Detailed explanation-2: -By drilling for ice cores and analyzing the air bubbles, scientists have found that, at no point during at least the past 800, 000 years have atmospheric CO2 levels been as high as they are now. That means that in the entire history of human civilization, CO2 levels have never been this high.

Detailed explanation-3: -Scientists use air trapped in the ice to determine the CO2 levels of past climates, whereas they use the ice itself to determine temperature. But because air diffuses rapidly through the ice pack, those air bubbles are younger than the ice surrounding them.

Detailed explanation-4: -CO2 Data from Ice Cores Robust evidence “only” spans back 800, 000 years thanks to ice cores providing high-resolution records in the form of air bubbles trapped under the freezing snow.