Kenai Fjords National Park is known for glaciers. These massive sheets of ice and snow slowly creep downhill or into the ocean and, along with ice caps, hold about 67.8 percent of the world’s fresh water. Unfortunately, the Kenai Fjords National Park glaciers, like other glaciers around the world, are shrinking due to climate change. While this can have detrimental environmental impacts, the melting glaciers can also harm the park's tourism.
A study from the University of Washington and the National Park Service (NPS) analyzed how glaciers in Kenai Fjords National Park changed over 38 years. According to a press release, 13 of the 19 glaciers in the park have retreated substantially — four are relatively stable and two have advanced. The park, which is nearly 670,000 acres, has various glaciers. Some terminate in the ocean, some in lakes and some on land, according to a press release.
“These glaciers are a big draw for tourism in the park — they’re one of the main things that people come to see,” says lead author Taryn Black, a UW doctoral student in Earth and space sciences in a press release. “Park managers had some information from satellite images, aerial photos, and repeat photography but they wanted a more complete understanding of changes over time.”
Researchers found that glaciers like Bear Glacier and Pedersen Glacier — lake terminating glaciers — are shrinking faster. According to the study, between 1984 and 2021 Bear Glacier receded three miles and Pedersen receded two miles.
“In Alaska, much glacier retreat is being driven by climate change,” says Black in a press release. “These glaciers are at really low elevation. It’s possibly causing them to get more rain in the winter rather than snow in addition to warming temperatures, which is consistent with other climate studies in this region.”
An unexpected finding was that the sea-terminating Holgate Glacier has advanced in recent years and seems to be going through the natural process of advance and retreat. The only other glacier to advance during the study is the Paguna Glacier. During an earthquake in 1964, a rock slide covered the Paguna Glacier and kept it isolated.
While the six land-terminating glaciers showed signs of retreat, they did not recede as quickly as the lake-terminating glaciers.
Black pulled data from 38 years worth of satellite photos taken of the glaciers during the spring and fall. After tracing the outline of all 19 glaciers over the years — totaling about 600 outlines — she compared the lines to identify the rate of recession. A similar method was used to measure glaciers in Greenland.
This new data provides a baseline to measure climate change — warmer air temperatures and changes in precipitation — in Alaska so they can make predictions on how this will impact the glaciers in Kenai Fjords. This study has helped rangers understand how the environment in the park could change.
“We can’t manage our lands well if we don’t understand the habitats and processes occurring on them,” says co-author Deborah Kurtz of the U.S. NPS in Seward, Alaska, in a press release.
Kurtz is concerned about how the melting glaciers could impact waterways such as lakes and streams and what they could mean for local wildlife, and the people who visit the park.
“Interpretation and education are also an important part of the [NPS] mission,” Kurtz says in a press release. “This data will allow us to provide scientists and visitors with more details of the changes occurring at each specific glacier, helping everyone to better understand and appreciate the rate of landscape change we are experiencing in this region.”
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