ON "60 MINUTES": GEOSCIENCES PROFESSOR SAYS VENICE FACES EXISTENTIAL THREAT FROM RISING SEA LEVELS CAUSED BY CLIMATE CHANGE

Three of the Highest Tides Ever Noted in Venice Happened Last November

One of the world's cultural gems and the city of canals and gondola boats is facing an uncertain future, says a professor of geosciences. Venice, Italy, where floods at high tide have been occurring for decades, experienced three of the highest ever recorded in one month alone last year. The signs are unmistakable, says Princeton Geosciences Professor Michael Oppenheimer: the city's existence is threatened, and the major cause is climate change. John Dickerson reports from Venice on the next edition of 60 MINUTES, Sunday, Jan. 12 (7:00-8:00 PM, ET/PT) on the CBS Television Network.

"Venice is facing an existential threat essentially to the city as it has been," says Oppenheimer, a lead author in a landmark UN study on climate change that found sea-level rise worse than experts thought. Venice is ground zero. "The rest of the world should take the message that this is what the situation's going to look like in many places that they live in."

He tells Dickerson that places like Los Angeles, San Diego, Key West, Miami, Jacksonville, Savannah and Honolulu are among the cities to be most affected.

But it's already happening in Venice, where the La Fenice Opera House narrowly escaped catastrophe last November as the waters rose in its first story. Dickerson gets a tour of the areas where water rose nearly high enough to touch electrical wiring that would have caused a fire if water had reached it. The salt the tidal water leaves behind also poses a problem. Venetians refer to it as a cancer because it can eat away the mosaics and foundations.

Dickerson also reports on a controversial water repelling system being built where the waters of the Adriatic Sea flow into the lagoon surrounding Venice. Once finished, its giant gates are expected to keep back the highest tides enough to prevent historic flooding. The project was started 17 years ago.

Oppenheimer believes the U.S. needs to seriously address the rising seas. He warns, "By the year 2050, which is only 30 years into the future, many places around the world, including in the U.S., are going to experience their historical once-in-a-hundred-year flood level once a year or more... An event that used to cause severe flooding once a century, we're going to get that same water level once a year."

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