by The storm that sank the “Bayesian,” a luxury yacht anchored off the coast of Sicily, was sudden, violent and deadly – and scientists say it could be a warning of what’s to come as global warming fuels climate more extreme in the Mediterranean.
The superyacht, which was carrying 22 people, sank in the early hours of Monday morning, near the port of Porticello, claiming at least five lives. Rescue operations are still underway, hampered by difficulties in reaching the vessel, which is lying on the seabed at a depth of about 165 feet.
The incident shocked many. The Mediterranean, prized for its crystal, calm waters, is a prime summer destination for the super-rich and their super-luxuries.
But these waters can still be dangerous – one of the reasons thousands of people die every year trying to migrate across – and experts say it’s only getting harder as the human-caused climate change in the sea, making storms stronger and more intense.
The reasons why the Bayesian sank are still under investigation. “It was dark and there are no images available,” said Luca Mercalli, president of the Italian Meteorological Society.
But many believe the yacht was hit by a water spout – one of many types of tornadoes. The coastguard reported that the yacht had been hit by a tornado, and a water shortage was reported to the European Severe Weather Database around the same time. Storms that day led to at least two dozen reports of water leaks across Italy.
Thunderstorm waterspouts are narrow columns of air that occur over water, and develop with heat and moisture.
Most waterspouts are relatively weak “with a few seconds of strong gusty winds before moving on or dissipating,” said Peter Inness, a meteorologist at the University of Reading. “But some of them can be much stronger.”
There isn’t a lot of data available about water leaks because they often happen without looking out to sea, but there is evidence that they can be affected by ocean temperatures. A study conducted by scientists from the University of Barcelona, which focused on the Balearic Islands in Spain, found that water shortages are more likely when the ocean is very warm.
However, it is a step too far at the moment to draw a link between climate change and more frequent or intense waterspouts,” said Inness. They require several different conditions to form as well as heat, including winds and temperature differences between the air and the sea.
What is clear, however, is that climate change is causing more intense storms, some of which are fueled by warm ocean water.
And the Mediterranean is very warm, right now.
The water temperature around Sicily is about 30 degrees, Mercalli said. That’s 3 degrees Celsius (5.4 Fahrenheit) warmer than average for this time of year – a “huge” anomaly, he told CNN.
Although natural climate fluctuations, such as El Niño, affect the ocean’s heat, it is clear to scientists that it is being supercharged by human-caused global warming driven by the burning of fossil fuels.
When the oceans are warm, they are able to inject more energy into the atmosphere. This can translate into strong winds or rapid updrafts during thunderstorms, Inness said. Warm air is also able to hold more moisture, so when storms produce rain, it can be heavier and more intense.
Heavy thunderstorms that dump large amounts of rain, as well as downbursts — strong winds that come from thunderstorms — have increased in Italy and around the world in the past few years, Mercalli said.
The storm that hit Sicily reached the Mediterranean from the west, where it gained energy from high ocean temperatures, said Justino Martínez, a researcher at Spain’s Institute of Marine Scientists.
Spain’s Balearic Islands were particularly affected. Heavy rain last week caused flooded roads, forced evacuations and canceled flights and canceled yachts docked on the popular island of Formentera.
The storm then gained more energy before reaching Italy, Martínez told CNN. In addition to the water spout, other strong storms across Sicily brought torrential rain late Sunday, dumping more than 100 mm of rain, or 4 inches, in Brolo in less than four hours.
The Mediterranean region is at the forefront of the climate crisis. It’s called the climate change hotspot, and it’s warming about 20% faster than the global average. And the toll is evident in the region’s extreme weather, from brutal heat waves to violent storms that bring devastating floods.
“Global warming – and particularly the warming of the Mediterranean Sea – is likely to accelerate some potentially dangerous weather systems in that region,” Inness said.
Italy, surrounded by the rapidly warming waters of the Mediterranean Sea, is particularly affected. Last year, an explosion hit a ship on Lake Maggiore in northern Italy, killing four.
The country has also battled deadly “once in a hundred” floods that killed at least 14 people in May last year, while Sicily hit 48.8 degrees Celsius (119.8 Fahrenheit) last August, surpassing European temperature record.
Outside Italy, last year’s Storm Daniel, fueled by unusually warm ocean waters, claimed lives in Greece, Turkey and Bulgaria. But it was in Libya that the greatest destruction from the storm took place.
Flash floods killed thousands of people after a so-called medicane – a rare, hurricane-like cyclone in the Mediterranean that gains energy from warm water.
“Global warming is contributing significantly to all extreme weather events,” Mercalli said, “with huge costs to people and society.”
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