FROM THE FIELD
GlacierHub

Twin Ice Caps in Canadian High Arctic Have Disappeared

by |August 27, 2020
St. Patrick Bay ice caps

St. Patrick Bay ice caps. Source: Mark Serreze

Far away in the high arctic polar desert of Ellesmere Island in Nunavut, Canada, next to Greenland, were once the twin St. Patrick Bay ice caps. However, in NASA satellite images from July 2020, they are nowhere to be seen. This summer, the ice caps finally met their demise after decades of rising temperatures and unusually warm summers chipped away at the centuries of snow accumulation that created them.

satellite images of ice caps disappearing

On the left, a satellite image from August 2015 shows the St. Patrick Bay ice caps. On the right, an image from July 2020 shows the ice caps have disappeared. Source: Bruce Raup via NSIDC

These ice caps were once a stunning feature of the Canadian High Arctic. As Mark Serreze, director of the National Snow and Ice Data Center, described to GlacierHub, upon arriving at the ice caps for the first time in 1983, he noticed the “pristine white…and all the snowflakes were just sparkling like little mirrors.” He added, “it was the only place I’ve ever been where there was just absolute silence…I remember standing on this ice cap, I realized I could well be standing on ground that no one had ever stood on before.”

Research station on St. Patrick Bay ice caps. Source:

Research station on St. Patrick Bay ice caps. Source: Mark Serreze

The St. Patrick Bay ice caps, located on the Hazen Plateau, are not remnants of the last ice age, but rather, are thought to have formed during the Little Ice Age, a period of global cooling from the early 14th century to mid-19th century when glaciers and ice caps expanded in Europe, North America and Asia. Ice caps, a type of glacier, are especially common in high elevation, flat terrains in polar and subpolar regions. Dome-shaped and spreading in all directions, ice caps function like “miniature ice sheets.”

The Eureka weather station on Ellesmere Island can be seen in the distance. Source: NASA

Since 1959, scientists have been periodically monitoring the St. Patrick Bay ice caps’ regression. In July 2016, the ice caps were just 5 percent of their 1959 area, and Serreze projected that around the year 2020 the ice caps would disappear altogether. Warmer summer temperatures due to climate change have accelerated ice melt on the Hazen Plateau. While natural variability brought some cooler years that supported occasional growth of the St. Patrick Bay ice caps (e.g. cooler temperatures in 1982-83 resulted in growth of the ice caps from the previous year), the overall trend in the mass balances — changes in ice mass — has been negative since the 1960s.

The area of the St. Patrick Bay ice caps in 1959, 2001, 2014 and 2015, shown on a satellite image from NASA’s ASTER. Source: NSIDC

As Michael Zemp, director of the World Glacier Monitoring Service, told GlacierHub, “glaciers are among the best natural climate indicators…They are able to translate this small climate signal, like a centigrade warming over one century … into a change that is visible.” The rapid demise of these ice caps in less than a century is a stark illustration of the impacts of a seemingly small 0.75°C increase in global temperatures since 1850.

Moreover, the disappearance of the St. Patrick Bay ice caps is “an exclamation point, almost symbolic” of how the Arctic is experiencing the effects of climate change, said Serreze. Thus far,  ice bodies in the Canadian Arctic have shown less sensitivity to warming than those in places like Alaska and the Southern Alps. Zemp explained this discrepancy occurs because temperatures in the Canadian Arctic are well-below the melting point, so additional heat energy first just raises the temperature of the ice. When atmospheric temperatures reach the melting point, then the entire ice cap melts rapidly.

NASA ASTER satellite image of Ellesmere Island. Source: NASA

“St. Patrick Bay is an early warning and demonstration of what might happen to the big ice caps,” in the coming decades, said Zemp. The melting of the relatively small St. Patrick Bay ice caps themselves does not have significant effects. But the melting of other glaciers in Nunavut — such as the closely monitored Devon, Meighen, and Melville South ice caps, and the White Glacier — expected in the coming decades is concerning, Zemp added, because these larger glaciers could contribute to rising sea levels in the future.

White Glacier in 2008. Source: Jürg Alean via NSIDC

For hundreds and thousands of years, ice has been a permanent feature of the high Arctic. Although Ellesmere Island has few permanent inhabitants (Grise Fiord, the main settlement on the island, has a population of 129), Greenland, just across the Nares Strait, is home to Inughuit communities who have lived among surrounding ice bodies for decades. One study found that between 1910 and 1940, Inughuit settlement locations were influenced in part by their proximity to ice caps because people would “use the ice caps and glaciers as transportation routes, and as escape routes as well,” Bjarne Grønnow, an archaeologist at the National Museum of Denmark, told GlacierHub. Mobility was important for the Inughuit because seasonal fluctuations in sea ice necessitated movement, and the relatively flat terrain of the ice cap was easier for Inughuit people to traverse with their sledges than sea ice or glacier fronts.

Glaciers on Ellesmere Island. Source: Michael Studinger/NASA

“We think of ice caps as permanent features…To find out that [they’re] not, that’s remarkable to me,” said Serreze. The melting of the St. Patrick Bay ice caps foreshadows the changes that will occur in the High Arctic if current rates of warming continue. Regions once covered by miles of ice are now seeing the reemergence of the Arctic Tundra as ice bodies melt. Bryophytes, a group of plants that include mosses, now grow where ice bodies once stood.

The St. Patrick Bay ice caps are certainly not the first or the last bodies of ice to disappear in the Arctic and around the world. In July 2020, the last fully intact Canadian ice shelf on Ellesmere Island collapsed into the ocean, losing 43 percent of its area. In 2014, Iceland lost its first glacier to climate change, the Okjökull glacier. “When you start to look at something like these ice caps, it’s not numbers anymore. It’s something very, very real — that you can see ice caps die,” said Serreze.

Barnes ice cap on Baffin Island in Nunavut. Source: Michael Studinger/NASA

With the COVID-19 pandemic, “I’m hopeful that we’ve woken up to the fact that we as a species are very vulnerable to our environment,” Serreze added. If the Paris Climate Accord goal to reach net-zero carbon emissions by 2050 is achieved, many glaciers and ice bodies around the world will survive and continue to serve their role as freshwater sources, Zemp explained. While the ice bodies of the High Arctic might be smaller in the coming centuries, they would still exist for us to marvel at and appreciate from afar.

Ellesmere Island mountain tops. Source: Nathan Kurtz/NASA

GlacierHub is a climate communication initiative led by Ben Orlove, an anthropologist at the Columbia Climate School. Many of GlacierHub's writers are Climate School students or alumni.


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