Cracking the ice age code

To understand where the Earth might be headed, it's important to know where it's been.

Throughout its existence, especially over the last couple million years, the Earth has experienced periodic cold and warm intervals, known as glacial and interglacial time periods.

These cycles used to occur every 41,000 years. But somewhere between 1.2 million and 700,000 years ago, the cycle shifted to occurring every 100,000 years, a transition period known as Mid-Pleistocene Transition (MPT).

Recently published research in Science Advances from the University of Delaware sheds new light on how and why this change occurred.

The work was led by Chandranath Basak, assistant professor in the Department of Earth Sciences, and made possible through the International Ocean Discovery Program (IODP) Expedition 383 in 2019. IODP was a multi-country consortium that concluded in 2024 after multiple years of enabling scientists to study the seafloor.