Waves Could Swallow Rapa Nui’s Sacred Stone Guardians by 2080

By the end of the century, waves driven by rising seas could crash into Rapa Nui’s most sacred shoreline, flooding Ahu Tongariki and threatening dozens of other cultural treasures.

Scientists used advanced computer simulations to map the island’s vulnerabilities, showing how the encroaching Pacific could one day swallow the iconic moai statues that have stood for centuries.

Rising Seas Threaten Rapa Nui’s Heritage

Rising seas could push seasonal waves inland far enough to reach Ahu Tongariki, the famous ceremonial platform within Rapa Nui National Park, by the year 2080. The finding comes from a new study in the Journal of Cultural Heritage led by researchers at the University of Hawai‘i at Mānoa. Their analysis shows that coastal flooding may also place as many as 51 other cultural landmarks at risk, including the island’s world-renowned moai statues.

“This research reveals a critical threat to the living culture and livelihood of Rapa Nui,” said Noah Paoa, lead author of the study and doctoral student in the Department of Earth Sciences in the UH Mānoa School of Ocean and Earth Science and Technology (SOEST). “For the community, these sites are an essential part of reaffirming identity and support the revitalization of traditions. Economically, they are the backbone of the island’s tourism industry. Failure to address this threat could ultimately endanger the island’s UNESCO world heritage site status.”

“As we work to understand the impacts of future sea level rise, we provide information that not only enables us to maintain safe, functional spaces and infrastructure, but also to support thriving communities,” said Chip Fletcher, co-author of the study and dean of SOEST. “That means we must document threats to culturally significant places and assets, and develop plans to preserve and protect what matters to communities.”

Computer Simulations Reveal Vulnerabilities

To explore how rising seas might affect Rapa Nui, Paoa’s team created a digital twin of the area and used advanced computer models to recreate wave activity along the shoreline. They then projected flood scenarios under different sea level rise conditions. By layering these flood maps over geospatial data on cultural landmarks provided by local partners, the researchers were able to identify which heritage sites are likely to be inundated.

“Unfortunately, from a scientific standpoint, the findings are not surprising,” said Paoa. “We know that sea level rise poses a direct threat to coastlines globally. The critical question was not if the site would be impacted, but how soon and how severely. Our work aimed to set potential timelines by which we could expect the impacts to happen. Finding that waves could reach Ahu Tongariki by 2080 provides the specific, urgent data needed to incentivize community discussion and planning for the future.”

A Shared Threat Across the Pacific

The challenges facing Rapa Nui mirror those in other coastal areas of the world, including Hawaiʻi.

“While Hawaiʻi is invested in protecting coastal infrastructure from sea level rise, the irreplaceable coastal cultural heritage sites in Hawai‘i and across the Pacific face the same urgent threat,” Paoa added. “Our research in Rapa Nui serves as a vital blueprint, demonstrating how we can use science to forecast risks to sacred places, such as coastal heiau and ancestral burial sites. By developing and applying these methods we hope we can help protect what is precious to the people of Hawaiʻi—provided such work is guided by, and deemed appropriate by, the Native Hawaiian community.”

Planning for Future Adaptation

Paoa is now using available data on coastal flooding to examine potential sea level rise impacts on cultural assets in Hawai‘i. In the future, he and the research team, in collaboration with local partners in Rapa Nui, plan to further investigate potential impacts of sea level rise on the island’s coastal cultural assets and examine adaptation and mitigation efforts to safeguard the cultural heritage.

Reference: “Impacts of sea-level rise and wave inundation in the Tongariki Complex, Rapa Nui” by Noah Paoa, Charles H. Fletcher, Assaf Azouri, Matthew Barbee, Tiffany R. Anderson, Martin Guiles, Shellie Habel, Philip Thompson, Kristian McDonald, Camilla Tognacchini, Gabriel Wilkins Riroroko and Douglas S. Luther, 22 July 2025, Journal of Cultural Heritage.
DOI: 10.1016/j.culher.2025.07.004

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