Alessandra Bonomolo’s documentary tells the story of the Serenissima and shows that if its vulnerability is ancient, it is today greater than ever due to climate change and pollution. The mystery of the origins of Venicea film not to be missed this Thursday, September 14 at 9:05 p.m. on France 5.
Venice is it doomed to sink beneath the waters by the end of the 21st century? Faced with the gloomy predictions made by certain scientists, this in-depth documentary proposed as part of “Science grand format” invites us to worry without despairing.
Throughout a journey through time, but also through current reality marked by the deleterious effects of pollution in all its forms and global warming, the Serenissima appears in all its splendor, but also all its fragility.
The disastrous fate of the island of San Marco in Boccalama, which sank into the lagoon in the 16th century with its monastery, illustrates what could happen to the City of the Doges. Marine archaeologist Eros Turchetto explains: “There are houses, boats, a whole world buried in the lagoon, invisible today, but which is also part of the history of Venice. The region is exposed to prevailing winds as well as subsidence. This explains the disappearance of several islands over the centuries. »
To counter the erosion of the banks, in particular those of the Grand Canal, caused by the current, but also by boat propellers, geophysicist Fantina Madricardo scans the bottom of the waterways all year round using the imaging technique. acoustics, which makes it possible to detect faults and carry out reinforcement work.
The fact remains that the weight of the churches and palaces, all built on wooden piles, eventually causes the ground, made of soft sediments, to sink at a rate of 1 millimeter per year. In addition, the phenomenon of high tides, known as acqua alta, floods the city at an increasing rate. In 2019, 1.80 meters of water covered Saint Mark’s Square. A record. “Something is changing, the climate is out of whack », underlines oceanographer Georg Umgiesser. Thus, climate change accentuates the rise in sea levels and at the same time increases the frequency and intensity of floods. It remains to be seen whether the 78 floating dikes, each 20 meters long, recently placed across the entrances to the lagoon, and which rise to form a dam in the event of an emergency, will be enough to save Venice in the long term. In any case, they were effective four years ago!