Beachgoers swim and lounge seaside on a calm day on a Catalan beach. The waters are a clear light blue, the sky is partly cloudy, and colorful buildings fill the background.
Calm weather days might be slowly disappearing along the Spanish Mediterranean coast, like at this seaside town in Catalonia. Credit: Xu
Blue circle with white text reading "Visit Teach the Earth for classroom activities to pair with this ENGAGE article." "Teach the Earth" is a logo with lines and triangles depicting mountains above the words and a shape denoting waves below them.

Planning a vacation to the Spanish Mediterranean? A new study could help tourists home in on the best days to partake in their favorite recreational water activities using more than 60 years of weather and ocean data.

These data, available to the public and local businesses, revealed that conditions for active water sports are on the rise and calm weather, suitable for more leisurely coastal activities, is becoming more infrequent. The changing seasonality of weather conditions will affect the local economy, which relies on tourism, and points to how climate change is affecting the region.

Wind, Sun, and Surf

Anna Boqué Ciurana is a climatologist at Universitat Rovira i Virgili in Spain. She also regularly surfs along Spain’s Mediterranean coast, a popular destination for tourists and locals who enjoy seaside recreation. In recent years, climate change has made conditions less reliable in the summer months, threatening the existing tourist industry. Businesses want to expand their tourist season to better capitalize on sports such as surfing and sailing, a risky move if high-wind and high-surf days are unpredictable.

Partnering with the provincial government and businesses in Tarragona, Spain, Boqué Ciurana and her colleagues collected data on the state of the sea, including wave heights and wind speeds, from instruments installed on buoys along the coast. The records detail conditions for 1958–2022 near the coastal town of Calafell, just south of Barcelona.

The researchers used these data to tally “calm days” good for swimming, snorkeling, and stand-up paddleboarding; “brave days” with the high wind speeds ideal for sports such as parasailing, kitesurfing, and sailing; and “surf days” with tall waves. They tracked how the frequency and timing of each type of day have changed over 6 decades.

A woman in a wetsuit surfs in turquoise waters off the coast of Spain.
Climatologist Anna Boqué Ciurana surfs in Calafell, Spain. Credit: Toni Duran, courtesy Anna Boqué Ciurana

In 2022, Tarragona’s shores experienced roughly 8 more brave days, 3 more surf days, and 5 fewer calm days per month than in 1958, though the trends are still preliminary, Boqué Ciurana said. The peak period for snorkeling and other gentle recreation, typically July and August, has gotten shorter, whereas periods that are good for more active sports such as surfing and sailing have grown longer. Boqué Ciurana presented these results at the European Geosciences Union General Assembly 2023.

The researchers have partnered with the local government to make the climate and ocean data available to the public, “aligning the identity of the project with the identity of the territory,” Boqué Ciurana said. Their goal in the future is to help the local economy grow, make the most out of seasonal weather trends, and guide tourists as they plan their travels by providing daily or weekly forecasts.

Local Versus Regional Trend

This new analysis pointed to changing conditions in Tarragona, but the trends might not be the same everywhere along the coast.

This new analysis pointed to changing conditions in Tarragona, but the trends might not be the same everywhere along the coast, cautioned Isidro Pérez, an applied physicist at the University of Valladolid in Spain who was not involved with this research. Pérez has investigated the effects of climate change on weather across the Iberian Peninsula.

He and a colleague found that in contrast to the new study, the number of calm days increased 7%–13% in the past 35 years, whereas brave and surf days remained steady. He pointed out, however, that his work was an average across the peninsula, whereas Boqué Ciurana’s work was very location specific.

“At this point of the research,” Pérez said, “both results may be compatible.”

“With more detailed research, the contrasts among different sites would be visible,” he said. “The trend of calm days could be increasing in some sites and decreasing in others, although the global trend would be increasing in the region.”

Boqué Ciurana said her team hopes to expand the analysis to more towns beyond Calafell and to aid more tourists and businesses along the coast.

—Kimberly M. S. Cartier (@AstroKimCartier), Staff Writer

This news article is included in our ENGAGE resource for educators seeking science news for their classroom lessons. Browse all ENGAGE articles, and share with your fellow educators how you integrated the article into an activity in the comments section below.

Citation: Cartier, K. M. S. (2023), Spain’s seafaring sports see fewer calm days, Eos, 104, Published on 2 June 2023.
Text © 2023. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.