Rome – Brussels: Europe and the Arabs
Climate change is endangering the health of Europe's oceans, and the impact isn't limited to marine life.

According to a report published by the European news network Euronews in Brussels on Monday, a new study warns that ocean acidification threatens valuable underwater cultural heritage.

Researchers have found that the materials that make up many archaeological treasures are vulnerable to damage when the water's acidity (pH) decreases. Ocean acidification poses a serious challenge to the protection of underwater cultural heritage.

The study, coordinated by the University of Padua in Italy, examines how ocean acidification, a direct result of climate change, is accelerating the deterioration of underwater archaeological sites.

Scientists studied the rate of deterioration of historical materials through dissolution and biodegradation in marine environments, then integrated these findings into large-scale climate models, explains lead researcher Luigi Germanario.

The results were alarming. While the erosion of rocks was extremely limited in the pre-industrial era and remains relatively limited today, rising emissions could trigger an exponential increase in deterioration rates.

These changes will be "irreversible in the coming decades and centuries, influenced by the properties of the materials and the ongoing evolution of biological colonization processes," meaning the growth of microorganisms on the surfaces of submerged structures, Germinario told the Italian newspaper La Repubblica.

The study, published in the journal Communications Earth and Environment, indicated that "ocean acidification will pose a significant challenge to the protection of underwater cultural heritage, making conservation and adaptation policies more urgent than ever."

The researchers conducted underwater field experiments to simulate future scenarios of water acidification. The team worked in the waters off the Italian island of Ischia, where subsurface volcanic activity creates natural carbon dioxide "vents" that release the gas at near-pure ambient temperature, making the area a living laboratory for studying ocean acidification.

"It's a natural environment that allows us to see what the expected scenarios for the coming decades and centuries might look like, even at extreme acidification levels," said Germinario.

The team submerged slabs containing samples of various types of stone commonly used at cultural heritage sites.

These slabs were placed at different points around the carbon dioxide vents, exposing them to a wide range of acidity levels and acidification conditions.

In the lab, the researchers used a high-resolution optical topographic survey, an instrument that creates three-dimensional models of surfaces, to image and measure the effects of different acidity levels on dissolution and erosion.

"This allowed us to simulate what might happen to a stone artifact at a submerged archaeological site, both now and in the future," Germinario added. The most fragile artifacts were found to be those rich in calcium carbonate, such as marble and limestone, especially those with high porosity or fine grains.

The researchers point out that "the chemical composition of these materials is similar to that of coral reefs, whose vulnerability to climate change has long been recognized by scientists and the public."

The study concluded that the most endangered artifacts are those whose historical or artistic value depends on very fine details, such as sculptures, reliefs, and mosaics.

Italy boasts stunning underwater treasures, including the archaeological park in Baia, which features mosaics and marble floors from an ancient Roman city, and the Roman port of Ignazia in the Puglia region.

"Even seemingly minor surface deterioration can mean the loss of irreplaceable information," says Germinario.