"Earthquake in Lisbon raises concerns about urban structural vulnerability."

Lisbon experienced a restless early morning when, last Monday, a 5.3 magnitude earthquake shook the Portuguese capital. Although no injuries or significant damage were reported, this seismic event has raised alarms about the vulnerability of urban infrastructure, especially in a country with such a marked seismic history as Portugal. This was the tenth strongest earthquake recorded in the country since the 16th century, and its analysis presents an opportunity to better prepare the population for future seismic events. The epicenter of the tremor was located about 60 kilometers west of Sines, resulting in shaking that was felt in various parts of the continent. However, as Jorge Cruz, a seismologist at the Portuguese Institute of the Sea and the Atmosphere (IPMA), warns, the energy released in this event is "very small" compared to what a major earthquake affecting Lisbon could release. This warning is crucial for understanding the magnitude of the risk faced by the capital, given its dense population center. Experts from the IPMA have indicated that this earthquake will be the subject of several studies aimed at unraveling its origin and the mechanism that triggered it. Additionally, it has been recorded that at the nearest accelerometric station to the epicenter, the highest ground motion acceleration values in the recent history of the country were measured. This information is vital for scientists, as it will allow them to make more accurate projections about future seismic risks. Since the moment of the earthquake, at least nine smaller magnitude aftershocks have occurred, indicating that seismic activity in the region may not have concluded. The most recent aftershocks, which occurred in the early hours of Tuesday, have kept residents on edge. Meanwhile, the government has viewed this event as a test of emergency response capacity, but seismology experts consider that this earthquake serves more as a warning about the city's lack of preparedness. The reality in Lisbon is alarming: approximately 30,000 residential buildings do not have adequate seismic-resistant features. This is because they were built before 1960, just one year before the first regulations on earthquake-resistant construction were implemented in Portugal. History shows that the first legislation was approved in 1958, but it wasn't until 1990 that it was effectively applied, leaving a significant percentage of the capital's infrastructure vulnerable. The Lisbon City Council has responded to the situation by announcing a new application that will allow citizens to assess the seismic risk of their buildings. This tool could be fundamental for raising awareness and preparing the population for a potential natural disaster, providing information that has so far been absent from public discourse. In this context, experts are clear: improving existing structures must be a priority. Seismologist Cruz emphasizes the need to remodel and reinforce buildings, not only to meet current standards but also to ensure the safety of citizens in the event of future earthquakes. The lack of foresight can have devastating consequences, especially in a city where the seismic history is a constant reminder of the fragility of the land. Lisbon's history is marked by earthquakes, the most devastating being in 1755. While this recent event did not cause visible damage, the warning is clear: the earth will shake again. Nature cannot be predicted, but preparation can save lives. In this sense, the response from authorities and community involvement are crucial to mitigating potential damage in the event of a major seismic event. The recent earthquake is an opportunity for Lisbon to reflect on its past and build a safer future. In a world where climate change and other natural disasters are becoming increasingly common, planning and resilience are more important than ever. The city must take this warning seriously and act before it is too late, transforming the unease of last Monday's early morning into a collective commitment to safety and preparedness.