It was hanging from a thin nylon rope, about 250 feet from the bottom of an icy well. Looking up, I noticed the rushing water, blinding snow churning in a frenzy from howling winds, that was buffing the driveway, about 20 feet above me. I was glad to be out of the weather, hanging almost silently.
When my eyes adjusted to the lower light, I found myself staring into an abyss that was much larger than I thought we could find beneath the surface of the Greenland ice sheet.
All I could think of was, “This shouldn’t be here.”
It was 2018 and I was on an expedition with Will gadd, a Canadian adventure athlete, to explore moulins, or giant vertical caves, in the Greenland Ice Sheet. Will was already at the bottom of the well. From my vantage point, it looked like an insect with a headlamp.
At first glance, Will and I were a strange couple for an expedition. Will is one of the the best professional ice climbers. Hello there sponsored by Red Bull. He won the X Games, ESPN’s extreme sports competition, and was with Jimmy Chin, a professional mountaineer and filmmaker.
I, on the other hand, am a professor of geology at the University of South Florida. I teach college students about the physics of groundwater. I’ve dated … scientists. We do not share exactly the same social circles.
I ended up in Greenland with Will because I wanted to make an expedition film that focused on climate change. Will is in his 50s. Throughout his long career, he has seen climate change erase ice climbing and shrink glaciers. He pitched the movie to Red Bull and they liked it. And then the Under the ice the expedition was born.
Will remembered me because I wrote my PhD. dissertation on glacier caves and had been studying them for over 15 years. I was supposed to be the science expert, but I sure didn’t feel like someone staring at that inexplicably large hole.
I started my accidental journey to glacier cave expert in 2004 as a geology student at Eastern Kentucky University. A mutual friend invited me on a rock climbing trip with Dr. Doug Benn, a glaciologist at the University of St. Andrews, Scotland. As I skipped classes to explore and map caves near campus, Doug was studying how warm weather was melting the glaciers on Mount Everest into networks of lakes. Some of these lakes drained catastrophically through caves in the ice, occasionally with devastating consequences for the villages, dams and hydroelectric facilities below. Glaciologists did not understand how these caves were formed and therefore did not understand what controlled the drainage of the lake.
Between climbs, and later over a few beers, Doug and I became convinced that we could understand how glacial caves were forming in the Everest region, if only we could explore and map them. While I had never seen a glacier, and Doug had only briefly visited a few caves, we thought combining Doug’s glaciology and mountaineering expertise with my cave mapping and exploration experience could help us figure out how to explore some of the tallest caves in the world. world. , and probably even survive the expedition.
On our first expedition in November 2005, we spent around seven weeks exploring and mapping glacier caves at elevations above 16,400 feet in the Everest region, including the caves that were a short hike from Mount Everest base camp. . Gasping for air, we survived rock slides, ice falls, and cave floor collapse. And little by little we learned the secrets of the glacier caves.
We found that glacier caves in the Everest region were forming along bands of porous debris in the ice. Water from lakes on the glacier’s surface would flow through bands of debris and melt the ice around it to form a cave. The caves could rapidly enlarge as the melting rate increased, allowing entire lakes to drain through them.
Having unraveled my first scientific mystery, I was hooked. I completed my undergraduate degree in 2006 and began working with Doug and a growing list of adventurous collaborators to explore and map dozens of other glacial caves in Alaska, Nepal, and Svalbard, Norway, first as a graduate student, then as a postdoctoral fellow, and finally as a professor. . Along the way, I learned to photograph the icy darkness so that I could share our findings with scientists who lacked the technical skills to venture into glacier caves.
Discoveries we made trailing beneath the world’s glaciers over the next decade helped us document the role glacier caves play in mediating how glaciers respond to climate change. In Nepal, where thick layers of debris on the surface of glaciers should insulate glaciers from melting, we found that glacier caves were melting the ice beneath the debris. The caves were turning Everest’s glaciers into Swiss cheese and rotting them from the inside out.
In other parts of the world, including Alaska and Svalbard, glacier caves followed fractures in the ice and funneled rivers of meltwater into glacier beds. The rush of summer meltwater lubricates the contact between the ice and underlying rocks and causes glaciers to slide faster than they would if there were no meltwater.
Although he had explored glacier caves around the world before working with Will, there was one place he had not been able to explore: the interior of the Greenland Ice Sheet.
The Greenland Ice Sheet stretches more than 650,000 square miles, about the size of Alaska. If it were to melt completely, it could raise the sea level by 23 feet.
Every summer, rising temperatures transform the icy surface at the edge of the Greenland Ice Sheet into a network of rivers and lakes. All rivers and many lakes disappear into moulins and continue to flow into the ocean along the interface of the ice sheet and the bedrock below it. As meltwater flow toward that interface increases, friction between the ice and the bed is reduced, and the ice sheet accelerates, sending ice into the ocean faster than in winter.
Some glaciologists worry that as global warming causes more melting and new caves form in areas of the ice sheet that have not previously melted, increased lubrication could cause the ice sheet to dump ice into the ocean and raise the sea level faster than expected.
With funding from National Science FoundationI was able to establish remote camps to study how the flow of water into the caves affected the movement of the ice sheet during the summer. But I really wanted to go back in the fall, when freezing temperatures cut off the meltwater supply to the moulins and make them safe to explore. So when Will Gadd emailed me and asked if I wanted to “do something cool” in Greenland’s glacier caves, I was ready to go. He wanted to see if the ideas he had developed about glacial caves from other glaciers would work in Greenland.
Having worked in so many different glacier caves, I thought I had solved them. But as I hung in the middle of that huge frozen shaft in the Greenland ice sheet, perplexed by its sheer size, I realized that the glacier caves still held surprises for me and that there were more mysteries to be solved.
Jason Gulley is an associate professor of geology at the University of South Florida and an expedition, science and environmental photographer based in Tampa, Florida. You can follow his work at Instagram.
His field work in Greenland was supported by a grant from the National Science Foundation. His field work in Nepal was supported by grants from the National Geographic Society.