Secrets of Earth's climate in six-million-year-old ice

Secrets of Earth's climate in six-million-year-old ice

From PNAS Science Sessions by PNAS

January 12, 2026 · 10 min

About this episode

Sarah Shackleton discusses insights into Earth's climate derived from six-million-year-old ice cores.

Air quality and pet health Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Sarah Shackleton shares climate lessons learned from 6 million-year-old ice. In this episode, we cover: •[00:00] Introduction •[01:02] Paleoclimate and ice scientist Sarah Shackleton introduces the information researchers can glean from ice cores. •[02:02] She recounts the age extent of previous ice cores. •[03:03] Shackleton describes the Allan Hills Ice Area. •[04:35] She describes the method for ascertaining the age of air in an ice core. •[05:49] She explains the results of the study and the insights into the climate in Antarctica over the last 6 million years. •[06:32] Shackleton talks about the ice at the base of the core, and the research implications of the study. •[08:13] Caveats and limitations of the study. •[09:11] Conclusion. About Our Guest…

People in this episode

Guest: Sarah Shackleton

Topics covered

  • climate change
  • paleoclimate
  • ice cores
  • Antarctica
  • scientific research

Keywords

  • climate lessons
  • ice core research
  • Allan Hills Ice Area
  • Antarctic climate
  • paleoclimate science

Mentioned in this episode

Organizations: Woods Hole Oceanographic Institution

Books & works: Proceedings of the National Academy of Sciences

More episodes of PNAS Science Sessions

Explore listener stats, chart rankings, contacts and more on the PNAS Science Sessions podcast page.