Maureen Raymo on Lamont’s Living Library of Earth History

The paleoclimatologist and marine geologist talks about why the miles and miles of marine sediment samples in Lamont’s Core Repository are so important.

Marie DeNoia Aronsohn
April 16, 2019

maureen raymo portrait
Paleoclimatologist and marine geologist Maureen Raymo directs the Core Repository at Lamont-Doherty Earth Observatory. Photo: Garry Tutte/SOI Foundation

Maureen Raymo is one of the most influential figures in her fields of paleoclimate and marine geology. Now, as she continues a path-breaking career, she has not only shaped our understanding of the how ice ages fluctuate and how sea levels change, but she is also among the world’s most honored researchers. Raymo was elected to the National Academy of Sciences in 2016. In 2014, she was awarded the Wollaston Medal of the Geological Society of London, becoming the first woman to win the award in the medal’s 183-year history. She joined the company of Victorian giants Charles Darwin and Louis Agassiz and such major 20th-century figures as climatologist Sir Nicholas Shackleton and James Lovelock, originator of the Gaia hypothesis.

Today Raymo is the Bruce C. Heezen Lamont Research Professor and the director of the Core Repository at the Lamont-Doherty Earth Observatory of Columbia University.

Q: When did you know you wanted to study the oceans?

I wanted to be an oceanographer by the time I was eight-years-old. My dad was making little cartoon books for me and my siblings. He asked each of us what we wanted our books to be about. Mine was my imaginary adventures with Jacques Cousteau. By that time, I had seen The Undersea World of Jacques Cousteau. The program had a powerful impact on me. I have always felt this connection to the ocean.

Q: How did you come to pursue your specific research?

I began my career in marine geology here at Lamont as a graduate student in the 80s, and I spent a lot of time as a student sampling cores in the repository. My particular interest was studying the history of the ice ages, the glacial/interglacial cycles that have characterized the last few million years. In particular, I looked at cores in the North Atlantic where I would examine ice-rafted detritus material that was brought in by icebergs and try to figure out what it could tell us about how cold the Atlantic was through time.

Q: How would you describe Lamont’s Core Repository, its history, and its importance to climate science?

The Core Repository has been at Lamont for decades. We are a facility funded by the National Science Foundation, and we operate as a working museum. We have over 40 miles of core drawn from almost 20,000 locations around the world’s oceans. We archive, curate and preserve them for posterity. We make samples available to scientists to study.

cores in lab
Lamont’s Core Repository contains over 40 miles of cores drawn from almost 20,000 locations around the world’s oceans.

Q: What exactly are cores and why are they so important?

Cores are the tubes of sand and sediment pulled from the ocean’s floor. They include everything that goes into the ocean, everything that washes in from land, is blown in by wind, or falls out of sky (in the case of volcanic ash) as well as all the fossil remains of microorganisms that live and die in the ocean. All of that material falls to the bottom of the ocean and accumulates layer by layer, stratigraphically — with the deepest sediments being the oldest and the sediment at the seafloor being the youngest. So, cores are like a tape recorder of what went on over the Earth through time.

Q: When did Lamont begin gathering cores?

One of the original undertakings of Lamont, which was established 70 years ago, was to study the world oceans in the aftermath of World War II and during the Cold War era of submarine warfare. Lamont had two research vessels. They were nearly always at sea and rarely came into the port, and among their activities was coring the bottom of the ocean to see what was down there. Because of this practice, tens of thousands of cores came back to Lamont where we now archive and study them.

Q: What discoveries were made possible by studying cores?

Probably the most exciting information that scientists were able to extract from cores has to do with the climate history of the Earth. Almost everything we know about how the planet’s climate changes naturally through time we have learned through the study of deep-sea cores over the past few decades.

Q: How do researchers extract information from cores?

The material that is in these cores is very fine, ranging in size from fine clay to the size of a grain of sand. Analyzing cores involves a tremendous amount of time at a microscope. I love sitting at a microscope for hours, looking at the fossils in the cores, organizing them by species, and picking out certain ones for geochemical analysis.

Q: Are the cores in the Core Repository relevant to ongoing research?

Yes. Our collection has been amassed from all over the world, and the cores are a valuable resource. It has become much more difficult to secure financial support to go out to sea. The heyday of vast ocean exploration seems to have passed. So, when researchers want to study a region they can come here and often find existing material rather than going through a long multi-year process of trying to get out there on a ship. Many of our cores have never been examined beyond the initial description when they were collected. Only about half have been studied in depth. Every now and then people strike gold in here, finding overlooked cores and generating new data that lead to important scientific papers.

Q. So there are still secrets here at the repository?

Yes, there are still secrets to discover.

This interview was originally published in Lamont’s 2018 Annual Report.