O yellow warning risk eruption of the Cumbre Vieja volcano on the island of La Palma (Spain) off the west coast of Africa, brought concern to many Brazilians, who expressed on social networks, for example, fear of the possibility of a tsunami hitting the country.
the phenomenon would only be checked in case of an explosive eruption, which has a low risk of occurring. Also, alert 2, on a scale of 4, can stay that way for many years without an eruption.
The hypothesis that the volcano could cause a tsunami that would hit Brazil was raised in 2001 by two of the greatest researchers in the world: Steven Ward, from the Geophysics Institute of the University of California (USA); and Simon Day, Department of Geological Sciences, University College, London (England).
They published a scientific article in which they warn the Atlantic countries. To reach the conclusion, the researchers mapped several points, such as seismic activity, the history of eruptions and ocean currents.
According to them, the last eruptions of Cumbre Vieja occurred in 1949 and 1971, but without causing problems related to tsunamis. “No other major tectonic earthquake has occurred under La Palma in the last three decades,” they said 20 years ago.
In recent weeks, however, seismic activity in the region has intensified again, which has increased the level of risk of eruption. The yellow level of a volcano is second on a scale of four and points to an even small possibility of an eruption.
journey by sea
In their simulation of an explosive eruption, the impact area, 250 km in diameter, would be capable of producing tsunamis in different directions and “several waves hundreds of meters high hit the coasts of the three islands west of the Canary chain .”
According to the analysis, it would take only 15 to 60 minutes for the Canary Islands to be hit by waves 50 to 100 meters high and for the African continent to receive the first impact.
Within nine hours, these waves would reach Brazil. “The tsunami’s vanguards (10 m) would initially reach North America. Simultaneously, larger waves (15-20 m) would reach the north coast of South America. Our computer models predict that the tsunami waves will be 10 to 25 m high, will be felt at transoceanic distances covering most of the Atlantic basin”, they pointed out.
Their concern is explained by the history of eruptions in the area. “Geological evidence suggests that, during a future eruption, the Cumbre Vieja volcano on the island of La Palma could suffer a catastrophic collapse,” they explained.
Over the past few million years, they say, “dozens of side-collapse landslides of a size comparable to that considered here [no estudo] were spilled from volcanic islands in the Atlantic.”
“If our models are correct, the tsunami of these incidents could sweep away coasts with good exposure to the sea,” they warned.
For Carlos Teixeira, a researcher at the Institute of Marine Sciences, UFC (Federal University of Ceará), there should not be a tone of alarm because of this scenario, nor are there any immediate risks.
“The volcano will not erupt tomorrow. We just have to make the plan because there is a risk; it is minimal, but we have to know what to do,” he says.
Even in case of an eruption, tsunami occurrence is not guaranteed. Teixeira states that only in the case of an explosive eruption would there be such a possibility.
“He can be on alert level for several years. It’s not like ‘goes on two, tomorrow goes on three and then goes on four.’ No! He can stay on this two for life and not have a rash.” complete.