If sea levels rise significantly, what will happen to Catalan beaches?

BarcelonaPutting up an umbrella, spreading out a towel, and jumping into the water has long been one of the best remedies for the heat. The persistent heatwaves may be putting things in question, and now another question arises from the continued rise in sea levels: Is Catalonia ready to maintain its beaches? The most optimistic projections for climate change predict a sea level rise of between 30 and 50 centimeters by 2100, but experts are increasingly inclined to consider more pessimistic scenarios. The most common prediction is that the increase will be more than 80 centimeters. Given this, traditional prescriptions are becoming obsolete, and scientists are designing innovative solutions to protect the beaches.

This question is raising concerns, as has been evident this year with the day. The challenges of coastal management organized by the Cartographic and Geological Institute of Catalonia (ICGC), with the participation of experts such as Leo Bejarano, head of the Catalan Climate Change Office. In line with data from the Copernicus Marine Monitoring Service, coordinated by the European Commission (EC), he emphasizes that the renowned meteorological observer Josep Pascual has observed since 1990 in L'Estartit that the sea level in Catalonia is rising on average about three centimeters every ten years. "It may seem like very little to us, but this has economic, social, and environmental implications that we cannot even imagine," Bejarano assures.

In addition to rising sea levels, we face other climate hazards, such as temperature, acidification, and extreme maritime storms, which "lead to coastal erosion and the loss of beaches," warns Bejarano, adding that 85% of Catalonia's population lives near the coast, and that they live near the coast. Therefore, doing nothing to mitigate the effects of climate change is not an option. Bejarano exemplifies this with a study on the costs that the authorities had to assume to repair the ravages of Storm Gloria in 2020, especially given "the lack of well-adapted coastal infrastructure": 287 actions cost 518 million euros.

Scientists are not sitting idly by, as was also evident this year at an informative session on rising sea levels at Barcelona's Casa Orlandai civic center. According to Vicenç Gracia, an engineer from the Maritime Engineering Laboratory at the Polytechnic University of Catalonia (UPC), the 80-centimeter increase by 2100 will mean that "there will be fewer and fewer places to lay down your towel" because beaches will be narrower. Faced with this, we can adapt—accept the loss of beaches—or increase defenses—resort to traditional engineering, such as building more seawalls or artificially replenishing the beach with sand—but he believes we need to go further with innovative solutions such as these:

Understanding the environment better: visors and ci

The Cartographic and Geological Institute of Catalonia has the Coastal Dynamics Information Service (SIDL), which provides a variety of open data and viewers, such as those for comparing the historical evolution of the coast or the effects of storms. From her laboratory at the UPC, Gracia adds that they have the Pitacora project, with which they build sensors for kayakers, scuba divers, and other users to collect data.

Nature-based solutions: planting posidonia meadows

This could be the case of planting Posidonia meadows on the seabed, a plant whose roots retain sand and whose leaves act as a wave energy attenuator. Several projects are underway to make this possible, and while many plants are still dying, Gracia is convinced that "in 10 years, replanting Posidonia will be a reality."

Warning systems like weather forecasts: Could the beach flood tomorrow?

The UPC laboratory has created an early warning system in Barcelona for possible flooding due to strong waves, providing forecasts in 8-hour time frames. According to Gracia, "everyone is hyper-accustomed to seeing tomorrow's weather, but not how to flood the beach," and the new system can be useful for predicting the days when it's best to avoid going near it. It has been in the testing phase since 2023 and will still take a long time to fine-tune, thus avoiding false alerts that could cause citizens to distrust.

Long-term planning: adaptation routes

"We're done planning in the short term as we've done up until now," Gracia emphasizes. Coastal adaptation routes to climate change are now being considered, incorporating various long-term strategies depending on the type of coast: the Maresme, with its trains, large buildings, narrow beaches, and relatively steep slopes, is not the same as other areas. The Generalitat (Catalan Government) is considering developing these scenarios and submitting them for public consultation within the framework of the future Coastal Protection and Planning Plan (PPOL), which is expected to be approved by 2027, according to its coordinator, Albert Grases, during the ICGC conference.