Ohio State Studies Greenland's Big Retreat
Most Ohioans will never see Greenland the way Michalea King has. The sun sparkling off the vast ice sheet that blankets the inland landscape. The crunch of walking across the glaciers—those slow-moving rivers of ice that run to the ocean like outstretched fingers. This land is too distant and harsh to welcome many visitors, but it’s also changing rapidly, to an extent that surprises researchers like King.
In August, she and her Ohio State colleagues issued a stark warning about the magnitude of that change. Scientists have known for years that Greenland’s glaciers are shrinking, but a study from the university’s Byrd Polar and Climate Research Center found they’re dumping so much ice into the ocean that the entire ice sheet has hit a troubling tipping point. The study, which analyzed satellite images from 1985 to 2018, described how Greenland’s glaciers began retreating much faster around the year 2000. As glaciers shrank, the rate of ice flowing from the interior sheet to the ocean sped up, says King, the lead author. That’s like opening the spillway on a dam, and the entire sheet has been losing mass ever since, says co-author Ian Howat, director of the Byrd Center. King and Howat previously expected the sheet to settle into some new equilibrium, but that hasn’t happened. Now, they’ve concluded it would continue shrinking even if global warming magically stopped.
Howat compares it to a bank account. Snow accumulation is our payday, and for the sheet to maintain balance, about half would be spent on surface melt and half on ice lost to the ocean, often as icebergs. In the 1990s, we began spending more on surface melting due to atmospheric global warming. The additional ice discharged into the water is as if we took out a mortgage on a new house. That mortgage is so large that even if we reeled in spending—by reverting to the climate of the early ’90s, before Arctic warming increased surface melt—the ice sheet’s balance would still decline.
The study’s results show that disturbances to the sheet caused by humans over just a few years can continue for decades, Howat says. “The firehose is still fully on without running out of water. And we don’t know yet when it will.”
The increased melting matters beyond the Arctic because Greenland is one of the biggest contributors to rising sea levels. But given its relative isolation and how far into the future the worst consequences lie, it can be hard to convince people to react with urgency, says King, who earned her doctorate in earth sciences this summer and is now working for the University of Washington.
The Byrd Center staff attempts to translate this polar science for laypeople with materials ranging from coloring books to virtual reality glacier tours made with videos of OSU scientists’ field work. They collaborate with local schools, clubs and organizations like COSI, and in a normal year they interact with 10,000 to 12,000 people plus an online audience, says Jason Cervenec, the center’s education and outreach director. The public seems more receptive to learning about climate change than ever before, though sometimes for dismaying reasons: It’s the leading topic of inquiries to the Byrd, but many people ask whether scientists actually agree on the cause. “For the last three or four decades, our understanding’s been very clear that the big driver is humans,” Cervenec says.
In conjunction with regional stakeholders and the city of Columbus, the Byrd Center also led a task force to create an adaptation plan detailing 43 actions Columbus should take to become more resilient to climate change, though it mostly doesn’t address ways to abate it. Mitigation will need to come at the federal, state and local government levels, and Cervenec says the prime example in Columbus is November’s landslide victory for Issue 1, which promises the city’s energy will come from renewable sources by 2023. It’s a step forward, albeit an incremental one when faced with a global crisis.
And it is looming large, as King and Howat’s study shows. “The moral of the story is things can get worse,” Howat says. But for the Byrd’s scientists, discussing the crisis is a delicate balance. They want to avoid hyperbolic, doomsday headlines while also providing a clear-eyed view of the ramifications so we can respond accordingly. They want to instill urgency and get Ohioans to think about ever-shrinking ice in a remote area most will never visit, Howat says. “These faraway places have direct impacts on us.”