By 2080 rising sea levels could cause seasonal waves to reach Ahu Tongariki, the iconic ceremonial platform that is part of the Rapa Nui National Park, a UNESCO world heritage site, according to a study published in the Journal of Cultural Heritage by a team of researchers from the UH at Mānoa. This coastal flooding also threatens 51 cultural assets in the area, including Rapa Nui'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
Paoa and his team built a detailed digital twin of the study site and used advanced computer models to simulate the wave environment along the coastline. They then mapped the projected flooding caused by waves under future sea level rise scenarios. The flood extent was then overlaid on geospatial layers containing the location of cultural assets provided to the team by local partners, which allowed the researchers to identify the cultural assets that will be flooded.
"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."
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 Hawaiʻi 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."
Paoa is now using available data on coastal flooding to examine potential sea level rise impacts on cultural assets in Hawaiʻi. 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.
The post Rapa Nui's iconic moai statues threatened by sea level rise first appeared on University of Hawaiʻi System News .
