Possible ways to mitigate the risk include armouring the coastline and building breakwaters to relocating the monuments.
The Journal of Cultural Heritage has published a new study indicating that rising sea levels could push powerful seasonal waves into Easter Island’s 15 iconic moai statues, in the latest potential peril to cultural heritage from climate change.
“Sea level rise is real,” said Noah Paoa, lead author of the study published on Wednesday and a doctoral student at the University of Hawaii at Manoa’s School of Ocean and Earth Science and Technology. “It’s not a distant threat.”
About 50 other cultural sites in the area are also at risk from flooding.
Paoa, who is from Easter Island – a Chilean territory and volcanic island in Polynesia known to its Indigenous people as Rapa Nui – and his colleagues built a high-resolution “digital twin” of the island’s eastern coastline and ran computer models to simulate future wave impacts under various sea level rise scenarios. They then overlaid the results with maps of cultural sites to pinpoint which places could be inundated in the coming decades.
The findings show waves could reach Ahu Tongariki, the largest ceremonial platform on the island, as early as 2080. The site, home to the 15 towering moai, draws tens of thousands of visitors each year and is a cornerstone of the island’s tourism economy.
Beyond its economic value, the ahu is deeply woven into Rapa Nui’s cultural identity. It lies within Rapa Nui National Park, which encompasses much of the island and is recognised as a UNESCO World Heritage Site.
The roughly 900 moai statues across the island were built by the Rapa Nui people between the 10th and 16th centuries to honour important ancestors and chiefs.
The threat isn’t unprecedented. In 1960, the largest earthquake ever recorded – a magnitude 9.5 off the coast of Chile – sent a tsunami surging across the Pacific. It struck Rapa Nui and swept the already-toppled moai further inland, which damaged some of their features. The monument was restored in the 1990s.
While the study focuses on Rapa Nui, its conclusions echo a wider reality: Cultural heritage sites worldwide are increasingly endangered by rising seas. A UNESCO report published last month found that about 50 World Heritage sites are highly exposed to coastal flooding.
A UNESCO spokesperson told The Associated Press news agency that climate change is the biggest threat to UNESCO’s World Heritage marine sites. “In the Mediterranean and Africa, nearly three-quarters of coastal low-lying sites are now exposed to erosion and flooding due to accelerated sea level rise.”
Possible defences for Ahu Tongariki range from armouring the coastline and building breakwaters to relocating the monuments.
Paoa hopes that the findings will bring these conversations about now, rather than after irreversible damage. “It’s best to look ahead and be proactive instead of reactive to the potential threats.”