Melting bergy bits are more serious than they sound, but this scientist found a way to study them
Climate change isn't just about massive ice sheets.
The Greenland ice sheet is nothing to thumb your nose at: Covering an area three times the size of Texas, it contains much of the world’s fresh water, influences Earth’s weather, and holds a priceless record of the planet’s climate inside. And if the entire thing melted, the world’s sea levels would rise by a whopping 23 feet.
As the planet warms, that possibility seems ever scarier and more likely. It’s melting, and fast. Luckily, there are scientists on the case—and they’re approaching their ice studies with plenty of creativity.
Take Daniel Frazier Carlson, an oceanographer at Aarhaus University’s Arctic Research Center who studies how icebergs melt. When faced with research challenges, he comes up with some pretty imaginative ways to study small chunks of ice that, though rarely studied, have big implications for the planet.
“I’m constantly surprised at how complex melting an iceberg can be,” says Carlson. How can you keep track of something that’s disappearing before your eyes?
It’s an esoteric challenge, and Carlson has chosen the most mysterious melting bits of ice to study: vexing chunks known as “bergy bits.” They’re the smallest pieces of what were once glaciers, then icebergs—in effect, rapidly disintegrating ice cubes that are both dangerous and difficult to observe.
The adorable moniker is apropos to much smaller chunks of ice that are between about 15 and 50 feet long. But the reason they exist isn’t so endearing: The ice cubes are signs of climate change.
They’re also a very real annoyance to researchers. Bergy bits are hard to detect and, with masses of up to 5,400 tons, can inflict serious damage on ocean vessels that can crash into the hard-to-spot chunks when veering away from larger icebergs. Since they weigh less than an iceberg, they float more fitfully on the water, which makes them even harder to study. These complications mean that bergy bits often don’t get accounted for in the bigger picture of ice melt and ocean circulation.
Carlson wants to change that, but it’s extremely pricey to study bergy bits. Commercial iceberg trackers can cost up to $5,000, and scientists often place them with the help of a helicopter, which can strain fragile budgets. “Since they’re so expensive, people want to get as much data out of [trackers on large icebergs] as possible,” says Carlson. “That limits the number that have been deployed in the past and the observational record has been biased toward larger icebergs.”
Needless to say, he experienced a sense of sticker shock when he realized how much it might cost to study bergy bits. So he did what any intrepid scientist does when faced with a seemingly insurmountable obstacle: get crafty.
Instead of relying on commercial trackers, Carlson decided to make his own. He invented something called the EXpendable Ice TrackEr (EXCITE)—a cheap, open-source device made with easy-to-find components. It relies on a repurposed GPS tracker usually used to alert people when someone’s made off with their bike or boat.
The tracker is powered by a lantern battery and stuffed into a PVC pipe. Voila—a waterproof, reusable tracker that costs less than $300 and takes just hours to build. And it doesn’t need a helicopter, either; Carlson simply tosses it on top of the bergy bits, and if it falls in the water, it floats. The tracker lets him study how the bits drift over the 30-day-or-so battery life of the device, determining how they accelerate and float over time. And when he put it to the test in the Godthåbsfjord, one of the world’s largest iceberg nurseries, he learned a lot about how the bergy bits operate.
“Everyone just assumes that the ice goes on this slow ride out toward the mouth of the fjord, but the tracker shows that they recirculate and move in circles,” says Carlson, who published his results, and more info about the tracker, in the journal Frontiers in Marine Science. “It confirmed my hypothesis that the fjord is a more dynamic environment than previously thought.”
The scientist also uses other low-cost tech to tackle the mystery of bergy bits, like drones and GoPros. Footage from both allows Carlson to create 3D images of the bergy bits, learn more about their bubbles, and compute the volume of the ice chunks. It also lets him study the bits over time so he can compute their melt rates.
“You basically just put the GoPro on a stick and drive your boat around the bergy bit,” chuckles Carlson. “You put it underwater as well.” This gives him the equivalent of a front-row seat to a chunk of ice that usually would be considered too dangerous to study. And since he relies on imagery instead of, say, sonar, he can be sure he’s getting data from the bergy bit itself and not nearby icebergs.
What’s the point of all this tinkering? For Carlson, it’s all about getting a more complete view of how ice melt impacts the rest of the world. Less dense, melting freshwater floats on top of saltwater, creating intense mixing that can decrease the amount of oxygen available to organisms at the bottom of the fjord. “If there are more icebergs produced, you could potentially have impacts on the biology that are detrimental not only for the ecosystem, but for the people of Greenland,” he says.
Carlson’s quick to admit that when it comes to tracking melting ice, he doesn’t have all the answers. The work is risky, cold and maddeningly dependent on weather and light. As a result, he’s increasingly working with unmanned tech like the NorthROV, a custom ROV that’s being tested in the fjord.
“It seems simple, but every time I think I’ve got something figured out I learn something new and everything changes,” says Carlson. Right now, his biggest enemy is the lack of information that’s driving his work in the first place. And lurking behind that challenge is an even bigger threat—the disappearance of the very ice he’s trying so hard to understand.
