Spain – an area at high risk of tsunamis

Perhaps it is a little known fact, but the Iberian Peninsula is considered by experts as an area of high risk for tsunamis. Some of Spain’s cities have, in fact, suffered the destructive impact of these large waves many times, especially in the Gulf of Cadiz and along the Mediterranean coast. And these waves have also caused thousands of deaths in Spain. Despite these facts, there is no emergency protocol in place in Spain, no tsunami warning system, no plans for damage limitation nor to somehow prepare the population in the areas of greatest risk.

ABC News reported that last Thursday, the Unesco international meeting on tsunamis was concluded in the Environmental Hydraulics Institute of the University of Cantabria, in Santander, which was attended by 80 representatives from over 40 countries. Geologists, physicists, seismologists, communications specialists and civil defence representatives, laid the groundwork for the establishment of early warning systems, similar to those that already exist in the Pacific, the Indian Ocean, Northeast Atlantic, Mediterranean and the Caribbean Sea. It is the first annual meeting of Unesco experts to be held in Spain.

During the meeting, the Hydraulics Institute of the University of Cantabria presented a comprehensive report in which, among other things, it stressed that if an earthquake occurred today similar to the one which shook Cadiz in 1755 (which was scale 9 in intensity and triggered a tsunami that killed 15,000 people), the death toll would be similar to that of the tsunami in Indonesia in 2004 – which killed nearly 300,000 people and left another million and a half homeless. Mauricio Gonzalez, a researcher at the University of Cantabria and coordinator of one of the work groups, says “the high risk Spain is running in case an event of this nature occurs, is by not having a warning system or any emergency protocol in place.”

Warning Sign

The tragedy which struck in the Indian Ocean in 2004 was a wake-up call for the world to suddenly realise that it was not prepared for this kind of disaster. In fact, only the Pacific Ocean had a tsunami warning system in place at the time. From that moment, Unesco launched and established a series of intergovernmental working groups in order to create similar systems in other seas of the world, including the Mediterranean.

The Spanish coasts have already suffered the impact of large tsunamis on numerous occasions. Historically, the areas most affected are the southwestern Atlantic basin (especially the Gulf of Cadiz) and the Mediterranean coast. Several investigations into the matter have already appeared in various specialised scientific publications such as “Natural Hazard” or “Earth System Sciences.”

As scientists know very well, tsunamis are closely related to earthquakes. And although not all earthquakes generate large waves, some of them, when certain conditions are met, can do so. The “tsunamigenic” seismic zones (which can generate tsunamis) that can affect Spain are right on the border between the African and Eurasian tectonic plates. It is in this narrow strip where all the earthquakes that have caused tsunamis in Spain are concentrated.

The Mediterranean

As for the western Mediterranean (Malaga, Granada, Almeria, Murcia and the Balearic Islands), the main sources of tsunami generation are in the north of Algeria and, further away in the Aegean Sea. If there is a tsunami off Algeria, in less than 30 minutes most of the Costa del Sol would be affected by the waves, and while the Mediterranean tsunamis are not as disastrous as those generated in the Atlantic basin, they are perfectly capable of flooding coastal lowlands. Recent studies show that Almeria, Murcia and many localities in the Balearic Islands, would be flooded with a tsunami of only 3 metres.

Most tsunami-prone countries in the Mediterranean basin are already taking preventive measures and starting to set up local warning systems. France, for example, has recently approved a budget of 12.6 million euros to establish its own warning system, but this is not so for Spain, where as yet no institution is officially responsible for tsunami hazard monitoring.