SEISMIC EVENTS

Portuguese residents were terrified when the ground started shaking on Monday morning. Scientist Deborah R Coen explains why they were right to worry - and how holiday destinations in Europe are at growing risk of earthquakes

- Deborah R Coen

There was no warning before the earthquake in Lisbon on Monday morning. Worse, the computer system of Portugal’s oceanic and atmospheric agency crashed shortly after the shaking began at 5.11am. No injuries were reported but residents, who were mostly fast asleep when it hit, have told of being terrified, jumping out of bed and “not being able to stand up”.

Patricia Brito, who lives in the centre of the city, says that, once she found her footing, she skidded into her parents thinking “this was the big one”. The shaking lasted less than a minute, but for three hours she couldn’t go to sleep as she and her friends WhatsApped each other from Setubal to Porto as they shared their stories. “One friend woke up and threw up a minute before it started, so she must have been hyper-sensitive to it coming.”

While the earthquake was moderate, with Lisbon 84km (52 miles) from its epicentre, the news dominated Portuguese and European headlines as it was felt in Gibraltar, Spain and Morocco. The panic among Lisboetas was also understandable as residents of the city are used to living in the shadow of 1755, when a massive earthquake collapsed Lisbon’s churches during mass, launched tsunami waves over the city’s walls, and caused fires that lasted six days.

Scientists estimate the magnitude of that devastating event was 7.7 compared to the 5.4 that occurred on 26 August. What would an earthquake of that size mean for Lisbon today?

Given that two-thirds of the city’s buildings were built before anti-seismic regulations of the 1980s, the damage could be untold, which is why residents of that city are often exposed to drills whether that is tsunami alarms that are tested near the waterfront of the city, or school children being given instructions of what to do in the event of a catastrophic event.