According to geologist Andrea Dutton, a 44-year-old assistant professor at the University of Florida, fossilized coral might hold the grim answers to the future of our swiftly warming planet. Not long ago, I walked with her through an old limestone quarry in the Florida Keys – the walls were etched with imprints of ancient corals that lived many thousands of years ago, when the seas were much higher than they are today. “I think of myself as a detective,” she says. “By understanding what happened in the past, we can get a better understanding of what might happen in the future.”
Specifically, Dutton is investigating one of the most important scientific questions of our time, one upon which millions of lives, and trillions of dollars in real estate and other investments, depend: As our planet continues to heat up, how fast will sea levels rise in the coming decades?
Much of Dutton’s research has focused on a period approximately 125,000 years ago, after the last retreat of the glaciers, when temperatures on Earth were almost the same as they are today, but seas were 20 or 30 feet higher. Where did that extra water come from – Greenland? Antarctica? Understanding how fast those ice sheets collapsed previously might offer clues to how fast they will collapse in the future. Dutton is particularly focused on West Antarctica, which contains enough ice to raise the seas by 10 feet. “If West Antarctica is unstable,” she says, “that could be a very big problem for coastal cities in the future.”
Dutton is not the only scientist interested in this question. But she has pursued it with a kind of urgency that belies her cool manner, traveling the world to seek out well-preserved fossilized coral outcroppings that help her learn the story rising water can tell about the sensitivity of the Earth’s climate. To Dutton, coral fossils can be read like tree rings, and dating how fast the corals grew on top of each other can reveal not just how high the water rose in the past, but how fast.
Still, it’s a fiendishly intricate tale – land is always in motion, rising and falling due to pressures from below, and the oceans are pushed around by gravity in mysterious ways. To come up with anything like an “average” sea-level rise for any point in history, Dutton has to factor in a startling amount of physics, from ice-sheet dynamics to glacial rebound of the North American continent. “The more you learn about how the Earth works,” Dutton says, “the more complex it becomes.”
Dutton is a single mom with two young kids. Her
Facebook page is full of pictures of their soccer games and stories like the
frog that accidentally got puréed in her garbage disposal. “I’m a
scientist, and I love my work,” she says. “But I’m not just doing
this because I love science. I’m doing this because I care about the future,
and the kind of world we’re leaving to our kids.” JG
