Venetian authorities are already searching for a successor to the Mose flood defence system (a network of massive retractable barriers sunk into the seabed at three lagoon inlets), just five years after it was inaugurated, as accelerating sea-level rise threatens to render it practically useless. Scientists warn that a projected one-metre rise in sea levels by 2100 could force the barriers to close around 200 times a year, choking the natural tidal exchange between the Venice lagoon and the Adriatic and turning it, in the words of one leading scientist, into a "filthy pond." The head of the city's newly formed Lagoon Authority has announced a global call for ideas spanning science, economics, and the arts, stressing that Venice — which has remained dry through 154 barrier activations since 2020 — cannot afford to wait another five decades for a solution.