Mohenjo Daro – A symbol of the threat of global warming to cultural heritage

In this file photo taken on February 9, 2017, visitors walk through the UNESCO-listed archaeological site of Mohenjo Daro, about 425 km north of the Pakistani city of Karachi. — AFP/File

PARIS: One of the first cities in the world was almost wiped off the map during the tragic floods this summer in Pakistan. However Mohenjo Daro survived, it has become a symbol of the threat that global warming poses to the cultural heritage of humanity.

Built around 3000 BC. BC by the Indus civilization in present-day South Asia, Mohenjo Daro was not washed away by floods, probably thanks to the genius of its designers.

Perched above the Indus River, the city had a primitive drainage and sewage system, which meant that much of the flood water could be drained away.

Nearly 1,600 Pakistanis dead in floods and 33 million others have been affected by a disaster “likely” made worse by global warming, according to World Weather Attribution, a network of researchers.

The ancient metropolis “could have disappeared with all the archaeological traces” it conceals, estimates Lazare Eloundou Assamo, director of the World Heritage program at the UN agency UNESCO.

The Pakistani site was “victim” of climate change and was “very lucky” to still be around, exactly 100 years after its discovery in 1922, Assamo said.

Fortunately, “the situation is not catastrophic” at Mohenjo Daro, said Thierry Joffroy, a specialist in brick architecture who visited the site on behalf of UNESCO.

Despite ground subsidence in some areas and water damage to some structures, the site “can be repaired,” Joffroy said.

“Huge impact”

For 50 years, the Paris-based UNESCO has compiled a list of World Heritage Sites, important places deemed worthy of protection, and this week marks a milestone in Greece.

“To protect this heritage ourselves (…) is to face the consequences of climate change and the loss of biodiversity. This is the main threat (…) that we assess in a tangible way”, declared Thursday the director of UNESCO, Audrey Azoulay, during the Delphi conference. .

Of its 1,154 World Heritage sites, “one in five sites, and more than a third of natural sites, already see this threat as a reality,” she said.

“We know of many other incidents of floods, hurricanes, cyclones and typhoons,” said Rohit Jigyasu of the International Center for the Study of the Preservation and Restoration of Cultural Property (ICCROM).

“We have these climate-related disasters, which have a huge impact on sites, for example, Mohenjo Daro,” he said.

Huge wildfires have scorched Canada’s Rocky Mountains, which are a World Heritage Site, and this year the flames have come within 15 kilometers (nine miles) of Delphi as a heat wave intensifies the severity of forest fires in the Mediterranean basin.

In Peru, meanwhile, landslides have occurred this year at the foot of Machu Picchu in the Andes mountain range.

Other less noticeable changes can also have serious consequences.

In Australia, the protected Great Barrier Reef is experiencing bleaching episodes due to rising water temperatures.

In Ghana, erosion washed away part of Fort Prinzenstein, which is preserved as an important slave trading post.

Termites and drought

“Slow factors” that don’t have an immediate impact pose “new kinds of risks in many of these sites,” Jigyasu said.

These include invasions of wood-eating termites in areas that were previously too dry or too cold for the insects to thrive.

In other countries, soil drying due to lower rainfall can have a “destabilizing” effect on some heritage sites, said Aline Magnien, director of the French state-funded Historical Monuments Research Laboratory.

In drought conditions, “the soils contract and…shake the foundations” and then “swell suddenly when it rains”, causing cracks, she explained.

When they are dry and hard, they absorb less water, which promotes flooding.

“We may have certain heritage sites that we will not be able to save, that we will not be able to transmit, which will perhaps be doomed to disappear”, estimates Ann Bourges, researcher at the French Ministry of Culture.

“It’s not just heritage that is affected when you lose part of it, but the whole social system that surrounds it,” added Bourges, who is also secretary general of the International Council on Monuments and Sites (Icomos). , an NGO.

In Mongolia, archaeological sites were abandoned and then looted because “the population no longer had access to water”, added Jigyasu.

Projected water shortages in the future could also lead to an increase in conflicts in which important heritage sites could be lost.

Teresa H. Sadler