The Increasing Intensities of Pleistocene Ice Ages

There have been 50 Ice Ages over the past 2.6 million years, and scientists refer to these Ice Ages as Glacials. Ice Ages alternate with warm climate phases known as Interglacials, like the one present day earth is experiencing, Scientists recently analyzed how intense each Ice Age was compared to others. They used data from 16 sediment cores taken from ocean bottoms in addition to ice core data from Antarctica. Scientists can determine past average annual temperatures by analyzing the isotopic values of subfossil foraminifera, and oxygen from air bubbles trapped in ice. Foraminifera are tiny sea creatures with shells. Each species of foraminifera lives within certain temperature parameters, so the presence of certain species in the sediment can help determine what the sea temperature was when they occurred there, plus the isotopic value of their shells is directly correlated with the temperature of the ocean when they were alive. Each level of the sediment core is radiometrically…