A group of scientists has revealed four drastic solutions to save Venice from rising sea levels. We need to get to work now, before it’s too late.
Venice is sinking as sea levels rise, with all signs suggesting that Italy could lose that UNESCO World Heritage Site within the next three centuries.
A in order to try to avoid the announced death of the “floating city”, a team of scientists examined four solutions to protect it before it sinks forever beneath the waves.
Led by oceanographer Piero Lionello, from the University of Salento in Italy, the team explored, in a study this Thursday at Scientific Reportshow well the four options would work: mobile barriers, ring dikes, close the Venice Lagoon and relocate the city.
Although Venice is affectionately known as the “floating city” (as we already mentioned), this is a mistake – comes out to .
For over 1,600 years, the city has kept its head above water on millions of wooden pilings, and it’s honestly pretty impressive that they’ve held out this long.
In addition to rising sea levels due to climate change, it is important to note that the The land on which Venice stands is sinking.
Over the past 150 years, the city, its islands and the lagoon in which they sit have faced increasing floods.
Of the 28 extreme flooding events that have hit Venice, in which more than 60 percent of the city was underwater, 18 have occurred in the last 23 years.
Venice’s only protection against the storm waves of the Adriatic Sea is currently the narrow barrier island that runs along the shore of the lagoon, and three movable barriersintroduced in 2022, which may close their entrances.
The team concluded, however, that It will take much more than that to protect the canal-filled city from succumbing to its own watery grave.
Basing their estimates on previous engineering projects and predictions of local sea level rise, they ultimately presented the solutions.
The open lagoon
The first option – continuing with this “open lagoon” strategy – involves closing the lagoon inlets using movable barriers whenever the flood risk reaches a certain level.
While this strategy is better than simply doing nothing, modeling based on the IPCC Sixth Assessment Report suggests that even these additional measures become ineffective when sea levels rise by 1.25 meters – a milestone that will likely be passed by 2300, even in low-emissions scenarios.
“As closure frequency increases, the likelihood of operation failure or delay increases, reducing the level of protection provided to monuments and the safety of residents,” the study explains.
Ring dikes
This option essentially involves surrounding Venice’s main features – the main island and its neighbors – with circular barriers about 3 meters high that would isolate them from the changing waters of the outer lagoon.
While this could provide adequate protection against a sea level rise of up to 6 meters, the study notes that it would have a detrimental effect on the city’s connection to the lagoon’s ecosystems and the general atmosphere, which could affect cultural heritage and tourism.
The closed lagoon
Another option is to completely close the lagoon, raising the level of the barrier island and permanently blocking the entrances to the lagoon, which are about 5 meters high.
This option brings several benefits, namely the fact that it can protect the city against a rise in sea level of up to 10 meters.
While this strategy preserves the city’s monuments, housing and tourism, it sacrifices the lagoon’s natural ecosystem that has historically shaped it. Furthermore, it would also mean the end of Venice’s life as a functional port.
There is also the issue of ensuring that the water does not stagnate.
The end of the floating city
The last option is relocate Venice residentsits monuments and important buildings, and end the floating city.
That would be a massive, and devastating, undertaking. It would also mean allowing the lagoon ecosystem to succumb to deeper, warmer and more saline waters that sea level rise implies, the effects of which are unknown.
An uncertain future
As Science Alert writes, weighing the risks to Venetian heritage, culture, and lagoon ecosystems against the costs of protecting them is not simple, but with these estimates, policymakers and residents have a clearer idea of their options going forward.
At this stage, ring dikes or dams seem like the best options, but the new study warns that Policymakers and communities must start planning now.
