Cumbre Vieja

Height: 1,949m
Location: La Palma, Canary Islands (Spain)
Geographical location: 28 ° 34 ‘0 “N, 17 ° 50′ 0″ W: 28 ° 34 ‘0 “N, 17 ° 50′ 0″ W

Last eruption 1971. Trade winds drive clouds towards the Canary Islands. La Palma is located in the upper left.

Volcan Teneguia

The Cumbre Vieja (Spanish for old summit) is almost 2000 meters high and about 14 kilometers long. It is a chain of volcanoes in the south of belonging to the Spanish Canary Island of La Palma. The ridge extends approximately north-south and north, together with the adjoining Cumbre Nueva to the central mountain range in the southern half of the island.

As its name suggests otherwise, it is geologically younger than the Cumbre Vieja and Cumbre Nueva. The Cumbre Vieja runs a popular hiking trail. The route offers expansive views of the volcano on La Palma and the three neighboring islands of Tenerife, La Gomera and El Hierro.

Climate

The mountain range has a significant influence on the climate of the island. Together with the Caldera de Taburiente, it soars even higher n the north, dividing the island into a more humid eastern side and a dryer western half. The prevailing northeast trade wind air mass pushes against the mountain slopes.

The air rises and forms clouds. These clouds donate enough moisture to let grow on the slopes, extensive hardwood and pine forests. The summit region is however, already in control of the counter currents. It is therefore often dry and cloudless. Given the level of the temperature in the summit area, during the winter months it may temporarily fall below the freezing point.

Geology

The Cumbre Vieja is of volcanic origin. It consists of lava, tuff and volcanic ash. Many craters are displayed in sequence, the highest point is 1949 meters high Deseada. La Palma has been for several centuries, the most volcanically active island in the Canaries. Seven of the approximately 120 craters of the Cumbre broke out during the last 500 years. The Spaniards had the island at this time not fully captured, thus missing more accurate data. Documented eruptions were:

1585 of Tajuya, whose name comes from the Guanche. Its lava covered a large area of today’s community of El Paso.
1646 the 1598-meter-high San Martin, which formed to the east of Monte la Luna.
1676 to 1678 the 657-meter high around 3000 years old San Antonio, south of the village Fuencaliente today (Los Canarios).
1712 El Charco (English for puddle) in El Paso.

On 24th June 1949 in the village of San Nicolas the old crater Duraznero (1,820 meters) erupted and its lava flowed eastward. In early July of that same year the old crater spewed ash. Until September 1949 it flowed from the San Juan. This lava flowed around at the town of San Nicolas, but buried a few farms and houses. Human lives were not mourned.

In 1971, the last 438 meters broke off Teneguia at the southern tip of La Palma. The name of the volcano is from a sacred rock of the Guanches, the Roque Teneguia where there was a hot spring. South of the Teneguia, the Cumbre continues below sea level. Submarine volcanism shows the most active part of the Cumbre is still in the sea.

Potential tsunami risk

During the eruption of the volcano of San Juan in 1949 there formed a two kilometer long crack in the mountain slopes and the western half of the Cumbre slid a few yards off towards the west coast.

Geologists fear that there could be a further outbreak of water bearing magma rising from the Cumbre. Explosive evaporation of water makes the slope unstable. Up to 500 billion tons of rock could slip into the sea. Such a huge landslide could cause a mega tsunami in the Atlantic. The tidal waves could pile up immediately after the landslide a few hundred meters high and reach speeds of up to 700 km/h.

Such extreme waves can occur only when very large masses of rock fall at high speed into the water. Since the water can no longer ebb over the rocks, they form instead in an air bubble, which displaces more water, thereby increasing the height of the wave. After about an hour, 100 meter high waves would hit in Morocco.

After seven or eight hours, the American continent would be reached, where 25 meter high waves would swamp the densely populated coasts of the United States, the Caribbean and South America. Even the European Atlantic coasts would be affected.

According to recent studies at the Technical University of Delft, such a landslide in the next 10,000 years is unlikely, because the Cumbre is not high or steep enough. Only if extremities such as very heavy rain was combined with exceptionally strong volcanic eruptions would any be possible. Calculations of the University state that forces would contribute up to 28 trillion Newtons.