VENICE (ITALY) — Six weeks after Venice was hit by the worst flood in its history, in November 2019, the city was inundated with four additional extraordinary tides. This shocked Venetians, and raised concerns about climate change’s potential impact.

This summer, the repeated infiltration of brackish lagoon waters into St. Mark’s Basilica is a quiet reminder that this threat hasn’t subsided.

“I can only tell you that we had tides exceeding a meter five more times in August than usual, which is unusual. “I am referring to the month of August when we are quiet,” Carlo Alberto Tesserin (St. Mark’s chief caregiver) told The Associated Press.

Venice’s unique topography is based on log piles interwoven with canals. This makes it vulnerable to climate change. Rising sea level is increasing the frequency and severity of high tides which inundate the 1,600 year-old Italian lagoon city. This is also slowly sinking.

Climate scientists and global leaders will be thinking about the fate of Venice’s coastal cities at the U.N. climate conference in Glasgow, Scotland that starts Oct. 31.

According to a new study by the European Geosciences Union, Venice’s worst-case scenario for sea rise by the end century is 120 cm (3 feet, 11 inches). This is 50% more than the worst-case global sea-rise average at 80 centimeters (2ft, 7 1/2 inches), forecasted by the U.N. science panels.

Its unique combination of architecture and canals, as well as its natural habitat and human ingenuity has earned it UNESCO World Heritage status for its exceptional universal value. This designation is at risk due to the effects of over-tourism, cruise ship traffic, and other factors. Although it was removed from the endangered listafter Italy prohibited cruise ships from passing through St. Mark’s Basin in Italy, alarm bells continue to ring.

St. St. Mark’s Basilica is a unique spot to observe the effects of rising seas on Venice. The piazza outside floods with 80 centimeters (30 inches) and water flows into the church at an 88 centimeter (34.5 inches). This is an increase from the previous 65 centimeters (25.5 in).

“Conditions continue to worsen after the November 2019 flooding.” It is now a regular occurrence that flooding occurs in these months. It is an everyday occurrence,” stated Tesserin, whose honorific, First Prcurator of St. Mark’s dates back to the ninth-century.