Dispatch From the Cryosphere: Amid the Glaciers of Antarctica and Chile

As my year of research on glacier dynamics and water security in Chile came to a close in December 2018, I started searching for ways to put my newfound knowledge to good use while also soaking up the Patagonian summer. Through a bit of finesse and luck, I found a glacier education and guiding position for a polar expedition cruise company called One Ocean Expeditions. I felt like I was walking in a dream as I boarded an ice class cruise ship departing from Ushuaia, Argentina.

Through the five trips I worked on earlier this year, I had the great fortune to visit and interpret a myriad of glaciers from the shallow coves of the Antarctic Peninsula to the deep labyrinth of the Chilean fjords. Each glacier told a unique story, but a common theme emerged that links them all. While these massive, flowing systems may humble us with their power and enormity, they are deeply sensitive to their surroundings and profoundly affected by human-induced climate change.

There were four sites in my travels from the Antarctic Circle (66°33’S) north to Santiago, Chile (33°25’S) that best illustrated this duality for me.

Wilkinson and Murphy Glaciers, Crystal Sound, Antarctica

The sun peaked over the horizon as we crossed into the Antarctic Circle and washed an orange light over the endless whiteness of the Stefan Ice Piedmont and Wilkinson and Murphy Glaciers. I couldn’t ask for a more majestic first glimpse of Antarctica.

Stefan is a modest size for an ice piedmont, a term to describe a low-lying expanse of ice that gradually slopes from the edge of a mountain to the sea. In comparison, the Wilkinson and Murphy Glacier complex is quite large, serving as an outlet for the Antarctic Peninsula Ice Shelf through a network of multiple glacial valleys that converge to tumble down to the sea.

We waded through a bay of asymmetrical, peculiar icebergs that rivaled the size of our eight-story ship. Unlike the more uniformed, tabular icebergs we later encountered, which had neatly separated from ice shelves, these icebergs likely calved off Wilkinson and Murphy or a neighboring tidewater glacier.

A view of the Wilkinson and Murphy Glaciers in Antarctica (Source: Kate Cullen)
Icebergs adrift near the Wilkinson and Murphy Glaciers in Antarctica (Source: Kate Cullen)

Crystal Sound set the stage for Antarctica as a dreamy, vast-beyond-comprehension, and complex continent of ice—a place that feels other-worldly until you realize these calving glaciers and massive melting icebergs feed the same ocean we all share.  

Avalanche and Astudillo Glaciers, Paradise Harbor, Antarctica

Moving north, Paradise Harbor proved to be my favorite stop on each trip. It offers the best of the Antarctic Peninsula in mid-summer—calm and beautiful scenery, feeding humpback whales, porpoising penguins, and playful seals. We would start the day with a hike from the Almirante Brown Argentine base to a gentoo penguin colony and up to a bluff with a sweeping view of the massive Avalanche and Astudillo Glaciers.

Avalanche Glacier offers a prime location for observing Antarctic wildlife. (Source: Kate Cullen)

One of my colleagues commented that in the seven years she has visited Paradise Harbor, she’s witnessed Astudillo Glacier recede noticeably. I’m yet to find an up-to-date study that could corroborate or rebut this observation, but it would be consistent with the behavior of the glacier in the late 20th century—displaying a frontal recession from 1973 to 1989 to the LIMA observations in the early 2000s.

A view of the Avalanche Glacier (Source: Kate Cullen)

Astudillo isn’t an isolated case. We know that in the second half of the 20th century, 87 percent of glaciers on the Antarctic Peninsula were in a state of retreat. This widespread trend of melting, as well as rapid temperature increases and the collapse of two major ice shelves, has made the Antarctic Peninsula one of the many ground zeros of climate change.

While our days were tranquil, I wondered what the collapse of the Larsen B Ice Shelf, just over the ridge, felt like here and what the break-up of the even larger Larsen C Ice Shelf will bring.

Serrano Glacier, Cordillera Darwin Ice Field, Chile

Although they were connected until about 40 million years ago, the Antarctic Peninsula and southern tip of South America today feel like two separate worlds. The hardy, dwarfed vegetation of the Cordillera Darwin is a wash of green in comparison to the Antarctic landscape, and the glaciers are smaller, more active, and radiate a rich blue hue.

Serrano is a northern-facing glacier deep in the Agostini Fjord and outlet for the Cordillera Darwin Ice Field, the third largest expanse of ice in South America. On a sunny and wind-free morning, we maneuvered closer to Serrano’s face and marveled at a thick medial moraine that traced up to the convergence of two upper branches of the glacier.

The Serrano Glacier, Chile (Source: Kate Cullen)

The Serrano Glacier, like the vast majority of glaciers in the region, is losing mass. Between 2000 and 2011, its area thinned at an average rate of about 1.0±0.4 meters of water equivalent per year and, overall, the Ice Field lost an average of -3.9±1.5 gigatons of ice per year.

What struck me about Serrano is how gorgeous, massive, and storied it is, while remaining practically anonymous—located in a region that few have even heard of, Serrano is rarely visited or studied.  

Pío XI Glacier, Southern Patagonia Ice Field, Chile

In contrast, Pío XI, also known as Brüggen Glacier, is one of the most famous glaciers in South America. At a whooping 1,300 square kilometers, it is about as large as Los Angeles and is the biggest glacier on the continent—and one of the only that is advancing.

Between 1945 and 1995, Pío XI advanced 10 kilometers at speeds of up to 50 meters per day, paving over 400-year-old trees and sealing off the upper section of the fjord, which brought about the formation of a lake. It has since slowed considerably, as warmer temperatures have caused more precipitation to fall as rain instead of snow and its primary flow path has shifted from the south terminus to the north.

Scientists surmise that Pío XI surged, while its neighbors continued retreating, possibly because of high snow accumulation in its abnormally large basin, fjord-glacier interactions, elevated water pressure beneath the glacier, changes in geothermal activity, or sediment build-up at its terminus.

Chile’s Pío XI Glacier spans an area about as large as that of Los Angeles. (Source: Kate Cullen)

Such a famous and peculiar glacier, I could barely contain my excitement as we cruised into Eyre Fjord and watched the gargantuan, blue mass come into focus from the upper deck. I trailed behind Australian glaciologist Ian Goodwin with his black beret and sharp goatee as we walked along Pío XI’s wide southern terminal moraine and searched for the source of a sediment-rich stream gushing out from the bottom of the glacier.

Pío XI was unlike any other glacier we’d seen—the water was saturated with sediment and free of icebergs, the face was a modest height and sloped away from us, and we observed no calving events that day. The preposterous amount of sediment and continuous purge of meltwater begged a closer look. We scribbled notes and took pictures to report back to colleagues and pondered how we could return with a scientific purpose.  

A cryosphere in crisis

The recent headlines in Greenland remind us the cryosphere is changing faster than we can grasp. Our modeling and monitoring is more accurate than ever, but the general public is just beginning to understand the complexity and urgency of the issue.

I found that these cruises offered a powerful platform to connect with folks from across the political spectrum through an immersive and emotional crash course in glaciology. I’m not yet sure how, but there must be a way we can create equally moving but more accessible and sustainable educational opportunities. As I reflect comfortably at home, Wilkinson and Murphy, Avalanche and Astudillo, Serrano, and Pío XI continue to flow.

Read More on GlacierHub:

Dispatch from the Cryosphere: Glacier Decrease in the Georgian Caucasus

South Asian Perspectives on News of Rapid Himalayan Glacier Melt

Ancient Humans of Glaciated Western China Consumed High-Potency Cannabis

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