Saturday, November 27

The eruption of the La Palma volcano has broken with the patterns set by history


History shows that the island had never faced a volcanic crisis of such caliber but, at the same time, the resilience shown by the palm trees each time the magma from the bowels of their land has broken the landscape. With the volcanic knowledge of the island and exhaustive monitoring, it has been possible to avoid fatalities and the damage, for the moment, is focused on the infrastructures of the place. Now it only remains to decide whether the future recovery will follow the steps of adaptation that the palm trees have shown throughout history.

No eruption, of the seven that the island has suffered, has been so well monitored like the current. Nor has there been one in which the population was “as vulnerable” as it is now. In this redounds the geographer of the University of La Laguna (ULL), Carmen Romero. “The area covered by the current eruption does not differ from that covered by other volcanoes on the Islands, but the population is much more vulnerable than 100 or 200 years ago.” The island today has a census of 83,458 inhabitants, according to data from the Canary Institute of Statistics (ISTAC).

However, in 1712, when the Charco erupted – the one that had devastated the largest surface so far – there were just over 15,000 living on the island. At that time, eight people from the area that is currently known as El Remo left their homes, and although El Charco is one of the worst-reported eruptions on La Palma, it is known that there was hardly any damage for this reason.

Tehuya, which erupted much earlier, in 1585, has a much more detailed description, and even scientific data. “The deformation, earthquakes, their behavior and even the location of the eruptive column were measured., which reached La Gomera and Tenerife “, explains Romero. From this eruption arose the Jedey phonolithic rocks, which today are better known as Los Campanarios.

The trace of the eruptions on La Palma.


Tacande 1430/1440, in fuchsia on the map

The unknown woman

This eruption occurred in the upper area of ​​El Paso, and never reached the sea. The chronicles highlight that a curse has been placed on the island and is related to the death of the nobleman Guillén Peraza.

Tehuya 1585, 34 days long, in purple on the map

Scientific data

Tehuya was the first eruption with a scientific follow-up. The deformation, seismicity and displacement of the ash were measured. From her arose the phonolithic rocks of Jedey

Martín 1646, 82 days long, in indigo blue on the map

Second mouth

The most characteristic thing about the Martín eruption was that, when it was losing strength, it opened a new emission center on the coast with Hawaiian characteristics. The wash created a low island.

San Antonio 1677/1678, 66 days long, in yellow on the map

More deceased

The San Antonio eruption left four dead in its wake. It combined explosive and effusive phases along a gap with ten emitting sources. Many crops were buried.

El Charco 1712, 56 days long, in blue on the map

The most similar

The Charco volcano is very similar to the current one. Its washes have been the ones that have devastated a greater surface, however, in it only eight people had to be evacuated.

San Juan 1949, 47 days long, in green on the map

The most explosive

San Juan is one of the strongest eruptions that La Palma has had. 1,000 people had to be evacuated and 100 houses were destroyed. Generated lahars with the first rains

Teneguía 1971, 24 days long, in orange on the map

A show

The Teneguía volcano is one of the ones that has done the most damage, but not because of its impact but because since then volcanism has been considered as not very dangerous and a spectacle.

Current 2021, 28 days to date, in red on the map

The most destructive

The eruption that is taking place in Cumbre Vieja is the largest that La Palma has suffered. 7,000 people have had to be evacuated and 700 hectares have been razed.

“All the historical eruptions have points in common and something that distinguishes them” like the one in Tehuya. The oldest of all, that of 1430 in Tacande, destroyed one of the most fertile valleys on the island and caused the death of many inhabitants. It was also the only one that did not reach the sea. “This gives us the most important clue in risk reduction”, warns Nerea Martín, geographer of the Chair of Disaster Risk Reduction and Resilient Cities of the ULL. “With these data we knew that not only the population centers at higher altitudes should be evacuated, but also those on the coast.” And it is that the researchers hoped from the beginning that the lava flow could cut the roads to the coast.

Most of the characteristics of the volcanoes of the Canary Islands that can be put into practice today have been learned from the research. The lava from the current volcano has emerged from several points, although all close to the main emission point. In fact, this past Friday a new mouth was opened 500 meters from the initial focus. Although the odds that I make it much further they are still tiny, is one of the signals that is being continuously monitored. It would not be the first volcano to do so, since it occurred in the Martín eruption of 1646. This volcano, which, like the rest, was fissure and Strombolian, when it was near its end, opened a second, more Hawaiian mouth, on the coast .

The consequences of this eruption are often confused with those left by the San Antonio in 1677. During 66 days the volcano combined explosive and effusive phases, like the current one. The lava was emitted along a large fracture of more than ten mouths and the ashes traveled to Tenerife. What the inhabitants self-evacuated –Which was the only way to survive at that time– the personal injuries were minor. Even so, four people died and many fields were completely buried.

The area covered by the current eruption is similar to that buried by other volcanoes, but the population is much more vulnerable than 100 years ago


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The problem with the eruptions in the Archipelago is that they are delayed so much in time that the canaries end up forgetting where they live. For more than 200 years, and after the devastation of the El Charco volcano, the inhabitants of La Palma came to forget that the land they walked on was born of fire, until in 1949 the bowels of La Palma roared with force once more. The San Juan volcano was the volcano with the highest explosive index to date, with phases of all kinds (explosive, effusive, mixed, calm and fumarole).

1,000 people had to be evicted from their homes, with at least 100 houses destroyed, though the majority (90) due to previous earthquakes and during the eruption. In this eruption, it was also learned that it is necessary to be on alert both during and after the volcano falls asleep forever. As Romero recounts, “in a few years the road traffic in the area recovered”, but the effects of the ashes were not taken into account. “With the first rains, lahars were formed that caused the loss of livestock and several victims among the workers who were in the area.”

After her, the palm trees, learned to take advantage of the land under the picón to recover their crops. Through the sorriba, a technique by which the ground is broken to look for the best land under the picón, they recovered them in a short time.

The one in Teneguía is, for this geographer, the eruption that has done “the most damage.” Not because of its impact on the population, which was minimal, but because of the perception that, since then, the Canaries have had about volcanoes. It had the lowest explosive index, it occurred on the coast where barely 1,500 people were evacuated and almost all their washes ran through the badlands of the San Antonio eruption.

Historical volcanism thus shows that the past can help both to understand what is happening in the present, and to distort the perception of risk. This new volcano should serve to prepare the Archipelago for future eruptions, but also to remind the Canaries of where the volcanic soil they tread on every day comes from.


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