Harvard Researchers Identify First Ever Proof of Sea Level Fingerprints

A new study conducted by Harvard researchers appears to have detected the first-ever proof of changes in ocean levels due to glacial melting, known as sea level fingerprints.

The study, led by Harvard professor Jerry X. Mitrovica and Harvard Ph.D. Sophie Coulson, could be key to predicting future sea level changes amid the effects of climate change.

“Sea level is one of the most complex and, I would say, detrimental impacts of climate,” Mitrovica said. “If you want to know what sea level is going to look like in 2100, then what you have to ask is what you think the Antarctic and Greenland ice sheets and glaciers will look like.”

When ice glaciers melt, ocean levels fall near the glacier and rise several thousand miles away due to glacial gravitational pulls — resulting in a pattern known as sea level fingerprints. While scientists have broadly agreed that sea level fingerprints exist, the study by Coulson and Mitrovica is the first to identify proof of it in nature.

Mitrovica said scientists have faced difficulties for years in identifying sea level rise that can be specifically attributed to glaciers because of the array of environmental factors that also raise ocean levels.

“You’re trying to pull out of this very noisy ocean of ours… a relatively small signal,” Mitrovica said.

Mitrovica and his team were able to observe sea level fingerprints thanks to European satellite data and a new method they used to account for the effects of wind and tides.

“We developed a way that we could correct for this wind-driven stuff,” he said. “Prior to our work, I think you’d have to probably wait another 20 years to see a clear fingerprint signal. But because you were able to see very close to the ice sheet that was melting, we shortened that timescale by decades.”

Mitrovica, who has studied the phenomenon of sea level fingerprints for years, said he was “overwhelmed” when he learned of his team’s research findings.

“For us, it’s a kind of bookend because we were the group that developed the ideas of sea level fingerprints,” he said. “I knew that it was there, but I just didn’t think we would be the ones to see it. I got quite emotional about it because we’ve written at least two dozen papers that have successfully refined how you make predictions of fingerprints.”

—Staff writer Jeremiah C. Curran can be reached at jeremiah.curran@thecrimson.com. Follow him on Twitter @jerryccurran.