Study: Rising seas could damage historical sites

The old city of Dubrovnik, clinging to the Croatian coast of the Adriatic Sea, is one major storm away from a flood that could cover 10 percent of a medieval city long known as the “Pearl of the Adriatic” and more recently as a main setting for HBO’s Game of Thrones.

It’s just one of some 40 treasured historical sites across the Mediterranean, including the winding canals of Venice and the ancient city of Carthage, at risk from rising seas, according to a new study published Tuesday in the journal Nature Communications.

The reason for their sweeping vulnerability is the same one that fostered so many civilizations in the Mediterranean to begin with. It’s the lure of the sea, dating back at least to the time of the ancient Phoenicians, who set sail from the now threatened sites of Byblos and Tyre along the coast of Lebanon.

“That’s just classic Mediterranean history,” said Joseph Manning, a professor of ancient Greek history at Yale University, who praised the new research.

“Everything is within two miles of the coast.”

But now, numerous Roman ruins, the original site of Carthage, historic regions of Istanbul and many other landmarks left by cultures ranging from the Phoenicians to the Venetians could be flooded in extreme storm events, or face growing erosion risks, said the research.

“What surprised me the most is that actually even under current conditions, there are so many world heritage sites that are at risk,” said Lena Reimann, a researcher at Kiel University in Germany and a lead author of Tuesday’s study.

In a world of rising sea levels, those risks will grow only more severe, threatening the destruction of irreplaceable cultural landmarks.

“We cannot put a value on what we will lose” if action isn’t taken to protect such sites, Reimann said. “It’s our heritage — things that are signs of our civilization. It cannot really be put in numbers. It’s more an ethical question, a moral question. We will not be able to replace them once they are lost.”

The study used the database of UNESCO World Heritage sites and projections of future sea level to arrive at its conclusions.

It found that out of 49 such sites along the coasts of the Mediterranean, 37 are already vulnerable to a 100-year storm surge event.

Many of the most at-risk sites were along the Adriatic Sea and included not only Venice but also the early Christian monuments of Ravenna, and the archaeological area and patriarchal basilica of Aquileia.

A closer look at the archaeological area at Aquileia gives a hint of just how much is at stake. Here, according to UNESCO, an ancient city “still lies unexcavated beneath the fields, and as such it constitutes the greatest archaeological reserve of its kind.”

In other words, a historical site that hasn’t even been uncovered yet could be damaged or lost.