Cool Job: Paleoclimatologist Rocks On Land And At Sea
by Amy Mayer
Maureen Raymo spent her childhood exploring the outdoors. By the age of seven she'd also developed an obsession with Jacques Cousteau, which fostered a fascination with the oceans. So by the time she got to Brown University in Providence, R.I., she had a passion for geology and oceanography and knew she'd have a science career. She says a campus job working for a paleoclimatology professor in the geology department introduced her to her life's work.
"This is where I discovered the field," she says, "which, as far as I could see, merged my two great loves."
As a paleoclimatologist, Raymo explores the climate conditions of the geologic past -- including what may have caused past climate changes.
"I've done this primarily through studying the historical records of geologic time preserved in deep sea sediments," she says. Raymo's oceanic research has twice led her to two-month expeditions on board the scientific research vessel JOIDES Resolution. The ship uses a gigantic drill to bore into the sea floor. Then it brings up columns of mud -- sediment cores-- that scientists on board immediately begin analyzing. Raymo first sailed while she was a graduate student at the Lamont-Doherty Earth Observatory of Columbia University in the 1980s, where she earned her PhD. Then, she returned as a co-chief scientist for another expedition in the North Atlantic in the 1990s. The scientists work feverishly, 12 hours a day, seven days a week, while they're at sea. Certain observations need to happen as quickly as possible after the cores come on deck. Other analyses can wait, and the cores continue to provide samples for researchers for years to come.
"The material that's collected is just a legacy," she says, "it's the sediment that keeps on giving." She works with graduate students and postdoctoral scholars today who are doing studies on cores that came up decades ago.
Studying Climate Change
In order to make sense of a past climate from mud, researchers have a variety of tools. Raymo's specific interest has been foraminifera, tiny fossilized critters. In a sediment core, the depth down the core correlates with a certain time in the geologic past. Raymo then analyzes certain species of forams (as they're called) at a specific depth, which gives her information about the climate conditions that existed in the past. In collaboration with other paleoclimatologists who use other tools, she and her colleagues have been able to determine, for example, that carbon dioxide levels between 3 million and 3.5 million years ago were about 400 parts per million -- that's just about the level we're at again today.
Reconstructing the climate conditions of the past (in addition to carbon dioxide levels, paleoclimatologists can determine sea surface temperature, sea ice extent and sea level) can help other scientists explore what is currently happening to Earth's climate and what the implications may be for the future. Climate modelers are people who build computer programs to crunch data and make predictions about what's going to happen in the future. To make more robust models, they rely on solid climate reconstructions from the paleo people.
It Takes a Village of ScientistsThree years ago, Raymo and a group of colleagues published a paper that discussed the need to reduce global carbon dioxide levels to preserve the Earth's environment as we know it. They recommended a worldwide reduction to at most 350 parts per million. That number prompted activist Bill McKibben to name his "global movement to solve the climate crisis" "350.org."
For Raymo, research is exciting and helps tame a relentless curiosity. In addition to occasional adventures on the high seas, Raymo's job is cool because she gets to collaborate with scientists all over the world, travel to myriad destinations to present her research, and continue to probe the larger questions of global climate change. Even as she explores one avenue of research, tangential questions invariably divert her attention, sometimes launching a new primary focus.
Raymo has worked at the University of California, Berkeley, MIT and Boston University, and this summer returned to her alma mater, Lamont-Doherty, as a research professor and director of the Lamont Deep Sea Sample Repository, which houses a collection of sediment cores. This fall she will be in Goa, India, on a Fulbright and hopes to work on a new aspect of her quest to understand the climate 3 million to 3.5 million years ago.
The current reconstructions don't provide sufficient information to determine what sea level was in various locations at that time, she says. One of the implications of climate change that has most grabbed the public's attention is how much oceans will rise as the planet continues to warm -- will Manhattan be under water in 100 years? Will the Maldives (a chain of islands in the Indian Ocean) disappear? Raymo says that with some basic geologic tools and skills, researchers can go to certain coastal locations and inexpensively get measurements that, collectively, will paint a portrait of sea level at that time. She'd like to amass data from a few dozen locations, and Goa could be one of them.
Do What You Love
Perhaps the coolest thing about Raymo's job is how much it still excites her. This summer she arranged to take a small group of non-scientists on board the JOIDES Resolution during a rare week when it was in transit and not carrying a scientific party. The group sailed from the Pacific side of Panama through the Panama Canal and into the Caribbean Sea. During the passage, Raymo gave some talks about her work, but she also toured all the parts of the ship that she never got to see while on board doing science -- the engine room, the bridge and even the kitchen. As someone whose career has depended upon the work of this boat, she has an unbridled affection for it. And since her previous expedition, the ship had been wholly renovated, including the science labs.
"The labs are just incredible -- they're all new and it's state of the art," she says. "I mean, honestly, if you were an earth scientist you'd be hard pressed to find labs as good as are on this boat anywhere in the world. It's all here."
Raymo says that she'd be happy to sail again with a science party, infecting another generation with her enthusiasm and knowledge, and perhaps adding another level to research scientists' understanding of past climate changes.