A Moved Church, an Eroding Townsite: Climate Change and Alaska’s Heritage Sites

Alaska has been warming twice as quickly as the global average since the middle of the 20th century, according to the Fourth National Climate Assessment, and faster than any other U.S. state. Shina duVall of the National Park Service's Alaska Region reviews what that is doing to the state's cultural heritage: an archeological dig washed away within a week, a church moved back from a cliff, a historic road covered by a landslide.

Excavation units at the historic gold rush townsite of Dyea were lost within a week of being dug, destroyed by the Taiya River. Emergency data recovery continues there (NPS/Shina duVall).

A great deal of ground, little of it surveyed

Alaska covers over 663,000 square miles and has more coastline than the entire lower 48 combined. The National Park System units in Alaska take in over 54.6 million acres, 65% of the whole system, and the largest, Wrangell-St. Elias National Park and Preserve, covers 13.2 million. The state has seven of the system's ten largest parks. It is the current and traditional homeland of hundreds of Indigenous cultures and language groups, with 228 federally recognized Tribes, 12 Alaska Native Regional Corporations and over 200 village corporations, and cultural resources in its national parks span more than 10,000 years. The author says any discussion of climate effects on culturally significant places should start with Indigenous people's experience, and that the Park Service should listen to Indigenous communities, scholars and experts and take their lead on adaptation.

The article says the archeological record is catching up with Alaska Native oral history, which holds that people have been in Alaska since time immemorial, and some of the oldest dated archeological sites in the Americas lie within the state. The state's Alaska Heritage Resources Survey lists approximately 45,000 cultural resources, yet only about 5% of the state has been inventoried, so the rest is unknown. Meanwhile, a report cited in the article finds that since 2014 there have been 5 to 30 times more record-high temperatures set than record lows. Stressors on heritage sites include permafrost melt, more freeze-thaw cycles, wildfire, flooding, storm surges and coastal and river erosion.

Park by park

Bering Land Bridge National Preserve and Cape Krusenstern National Monument. A multi-year survey of climate impacts at coastal archeological sites, started between 2012 and 2016, has found severe threats, with most sites extremely vulnerable to coastal erosion. A project planned to begin in 2024, with Portland State University, Kawerak and other groups, will revisit those sites for limited testing and non-invasive documentation. Researchers at Cornell University have also been measuring permafrost depth at two locations there, and are concerned that damage to buried cultural material from changing permafrost is worse than expected and may be accelerating toward irreparable loss.

Denali National Park and Preserve. Archeologists have seen artifacts likely eroded out of permafrost or ice patches, such as bone and antler arrow shafts believed to be around 1,000 years old, one found floating in a river and the other in a high mountain pass. By then, the author notes, the artifacts' context, the most significant data, is already lost.

Undated bone and antler arrow shafts found in Denali, most likely melted out of an ice patch (NPS/Phoebe Gilbert).

The Pretty Rocks landslide crosses the Denali Park Road at Mile 45.4, has completely covered a 90 m stretch, and led the park to close the road past Mile 43 at least through the summer of 2024. It has been active since at least the 1960s, and probably before the road was built through the area in 1930. Before 2014 it only caused small cracks and moderate maintenance every 2 to 3 years; by 2016 a slump had formed and monitoring began, and the road's movement went from inches per year before 2014 to inches per month in 2017, inches per week in 2018, inches per day in 2019 and up to 0.65 inches per hour in 2021. Denali's average temperature rose by more than 7°F in climate data from 1950 to 2010. The road is a 92.5-mile cultural resource on the National Register of Historic Places, under construction since 1922 and tied to scenic road development in the 1920s and 1930s and to the Mission 66 program of the 1950s and 1960s; the author says the landslide has irreversibly damaged its integrity.

Karluk church. The Park Service's Heritage Assistance Program lets staff support projects outside parks. The Ascension of Our Lord Church in Karluk, built in 1888, stood on a bluff that had been eroding rapidly for decades, and partners, including the community, the Russian Orthodox Sacred Sites of Alaska (formed in 2002) and the Park Service, had watched it since at least 2002. In March 2020 they judged the situation dire, and in August 2021 a large consortium moved the building approximately 80 feet inland. The churchyard holds outlying structures, remains from more than 6,000 years of occupation and the community cemetery, so the Park Service advised on site planning, documentation and preservation and monitored the move for disturbance to burials. Partners are still seeking a permanent site for the church and cemetery.

The Ascension of Our Lord Church, on the National Register of Historic Places, was in danger of falling into the Karluk River where it meets Shelikof Strait, and was moved inland (NPS/Dustin Reft).

Klondike Gold Rush National Historical Park. At the Dyea townsite, which boomed in 1897 and 1898, archeologists are working with the Skagway Traditional Council on emergency salvage excavation. The bank along the north edge has been eroding exponentially faster than at any time since the town was occupied: 125 linear feet and 64,000 square feet of land were lost to the Taiya River in 2021 and another 235 linear feet and over 97,000 square feet in 2022, with a conservatively expected 125 to 150 linear feet more in 2023, against an average of 66 linear feet a year before 2021. In the 2022 season, 1 by 2 meter excavation units were obliterated within days of being dug. The article attributes the flooding and channel shifts to higher river flow from more precipitation and glacial melt, a braided channel system turning into a single powerful channel (tied to reforestation after the gold rush as well as to climate change), and bank changes in the lower river, including armoring of the dike at the Taiya River bridge.

Lake Clark National Park and Preserve. The Clam Cove Pictograph Site, one of only two pictograph sites in the park and on the National Register of Historic Places since 2017, shows human-like figures, animal images (mainly sea mammals), boats and abstract markings; radiocarbon dates from artifacts collected there suggest an occupation about 1,700 radiocarbon years ago. Warmer temperatures are bringing more runoff, vegetation and lichen, flaking of the rock face, and water seeping through the sandstone. Staff have tracked the changes for over 15 years and can do little to slow them; the park keeps documenting the site under a conservation plan and keeps Tribal groups and nearby communities informed.

Surface runoff, lichen and vegetation growth are eroding and obscuring the pictographs (left); weather has caused spalling and exfoliation of the rock surface (right) (NPS/Jason Rogers).

Sitka National Historical Park. The Kiks.ádi Fort Site is where the Kiks.ádi Tlingit successfully fought off a Russian advance in the Battle of 1804, and it is tied to the Survival March, which cost the Kiks.ádi Tlingit their land, homes, possessions and clan regalia and kept them away from their home for 18 years. A riprap revetment has protected the site from the Indian River, which was expected to keep eroding at 3 to 6 meters a year, since 1985. A huge rain event in 2015 raised the river well above flood levels and badly damaged it, and park staff plan to rebuild about 150 feet of it, with the project scheduled to finish in 2027 and in consultation with the Sitka Tribe of Alaska. Staff are also confirming the exact location of the fort walls.

What is needed

The author says the work now under way falls short of what is needed to get ahead of the changes: partner engagement, condition and vulnerability assessments, prioritizing needs, documenting resources and, where necessary, lessening losses. Remote sites need helicopters, small planes or boats; staff also want better spatial modeling, data management and digitization tools, more emergency response training, and closer work with community and Tribal partners. The article also says managers will have to accept, at times, that some loss is inevitable.

Sources

• National Park Service, Alaska Park Science 22(1), Stories Yet Told: Alaska's Cultural Heritage in a Time of Unprecedented Climate Change, by Shina duVall, Alaska Region, National Park Service (2023); quotations from the United Nations, a 2014 article and an Ahtna Elder are left out; rewritten in hubnx's own words.