New Tool Tracks Climate Change’s Impact on World Heritage Sites

The online portal showcases the craggy cliffs surrounding Edinburgh Castle, Easter Island’s famed sculptures and other cultural heritage hotspots

The Moai sculptures on Rapa Nui are at risk of collapsing into the ocean as coastal erosion continues. Bjørn Christian Tørrissen via Wikimedia Commons under CC BY-SA 3.0

The International Council on Monuments and Sites (ICOMOS) has partnered with Google and 3-D surveying firm CyArk to compile a web database of five Unesco World Heritage Sites affected by climate change.

The portal, called Heritage on the Edge, features the stone sculptures of Easter Island; Scotland’s capital city of Edinburgh; the ancient Bangladeshi mosques of Bagerhat; the Tanzanian port city of Kilwa Kisiwani; and the adobe structures of Chan Chan, Peru. The project details each site’s story with photographs, 3-D models, and interviews with experts and local residents.

Climate change’s effects on the five locations range from erosion caused by crashing waves and buffeting wind to rising seas that threaten the integrity of cliffs, ocean acidification and torrential rain. Per Newsweek’s Rosie McCall, salt walter flooding poses a particular threat to the Bagerhat mosques, while rising sea levels and storms could “undercut the cliffs [the Moai sculptures] stand on,” leaving the giant heads ready to topple over into the ocean.

“Culture and heritage is about people, things that are important to people,” writes Andrew Potts, ICOMOS’ Climate Change and Heritage Working Group coordinator, in a Google Arts & Culture blog post. “And so when you make [the climate change conversation] a culture conversation you’re making it a people conversation.”

Kilwa Kisiwani, a port city off the southeastern coast of Tanzania, joined the World Heritage in Danger list in 2004. Constructed from coral and lime mortar between the 11th and 13th centuries, the trading hub was described by a 14th-century traveler as “one of the most beautiful cities, and elegantly built.”

More recently, overgrazing and the use of small fishing vessels have depleted the area’s shore-hugging mangrove trees, allowing waves to erode the coastline and ancient ruins nearby. To combat these issues, local communities have worked with international groups to replant mangroves and install walls designed to protect the shore from damaging waves.

Unesco removed Kilwa Kisiwani from its danger list in 2014, but much damage had already been done. As Madina Haji Khamis, a member of the Stonetown Conservation and Development Authority, tells Heritage on the Edge, inundation by rising seas has made the well she and her neighbors use for drinking water salty.

“It is no longer what it used to be,” adds Khamis.

At Easter Island, known to its indigenous community as Rapa Nui, climate change’s effects are written into the landscape. As captured in a 3-D model produced by CyArk, coastal erosion has already made some of the island’s monumental Moai statues, carved between roughly 1100 and 1600 out of stone mined from two volcanic quarries, collapse.

In some spots across the island, sea walls have been installed to protect the coast and statues from erosion, but other structures remain at risk of collapsing into the sea.

“They are not only heritage objects, but represent our culture and history, from my ancestors to my children,” explains Daniela Meza Marchant, Rapa Nui head of conservation, to Heritage on the Edge.

Each heritage site featured on the portal is accompanied by 3-D models, as well as interviews with local ICOMOS representatives and residents of areas surrounding the cultural hubs. Curious users can browse photographs, listen to audio clips, read histories and explore models of the sites. Some pages, like the one for Scotland’s capital city of Edinburgh, even include interactive graphics.

Heritage on the Edge has also published two augmented reality “pocket galleries” depicting the nine-domed mosque of Bagerhat and Kilwa Kisiwani’s Gereza Fort. Each gallery offers a short guide to spotting signs of deterioration linked to climate change.

In Chan Chan, Peru, users’ view begins in the middle of the adobe city. Its structures, made of mud and coarse sand, are deteriorating due to increasingly extreme and fluctuating weather. Wind erosion erases details from the monuments’ faces, while cycles of rainfall and drought cause crumbling. To combat these issues, Peru has established programs dedicated to reducing damaging water accumulation and managing coastlines.

“Climate change is a thing that scares many people, but there is hope,” says ICOMOS’ Milagros Flores to Heritage on the Edge. “It is about creating awareness, about being alert. To understand that this is the moment for each one to do their part, so that everyone puts their grain of sand in this great effort.”

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