The French Riviera, including the city of Nice, faces a 100% probability of a tsunami at least one metre high within the next 30 years, according to UNESCO. While the Mediterranean is often perceived as low-risk, historical records and modelling show destructive waves have hit the coast before and will likely do so again.
Tsunamis in the region can be triggered by earthquakes, underwater landslides, or volcanic eruptions. Run-up times can be under ten minutes for local events, such as the 1979 Nice tsunami caused by an underwater collapse, which killed eight people. Distant sources, like the 2003 Boumerdès earthquake in Algeria, can reach the coast in under 90 minutes, causing harbour resonance and damage.
Since 1970, tsunamis have killed over 250,000 people worldwide. In the Mediterranean, the highest number of historical tsunamis outside the Pacific have been recorded, with around twenty incidents along the French Riviera between the 16th century and early 2000s, often with waves exceeding two metres.
France's national tsunami alert system, Cenalt, can detect earthquakes and transmit alerts in under 15 minutes. However, for tsunamis with very short run-up times, preventive evacuation remains the only effective life-saving measure. Authorities are preparing evacuation plans to ensure coastal communities can respond rapidly.
