Teide
Teide or Mount Teide is a volcano on Tenerife in the Canary Islands. Its summit is the highest point in the Canary Islands and the highest point above sea level in the islands of the Atlantic. If measured from the sea floor, its height of makes Teide the third-tallest volcano in the world; UNESCO and NASA rank it as Earth's third-tallest volcanic structure. Teide's elevation above sea level makes Tenerife the tenth highest island in the world.
Teide started forming 170,000 years ago due to volcanic activity following a catastrophic landslide. Teide's base is situated in Las Cañadas crater at a height of around above sea level. Teide is an active volcano: its most recent eruption occurred in late 1909 from the El Chinyero vent on the northwestern Santiago rift. The United Nations Committee for Disaster Mitigation designated Teide a Decade Volcano because of its history of destructive eruptions and its proximity to several large towns, of which the closest are Garachico, Icod de los Vinos and Puerto de la Cruz. Teide, Pico Viejo and Montaña Blanca form the Central Volcanic Complex of Tenerife.
The volcano and its surroundings make up Teide National Park, which has an area of and was named a World Heritage Site by UNESCO in 2007. Teide is the most visited natural wonder of Spain, the most visited national park in Spain and, by 2015, the eighth most visited in the world, with some 3 million visitors yearly. In 2016, it was visited by 4,079,823 visitors and tourists, reaching a historical record. Teide Observatory, a major international astronomical observatory, is located on the slopes of the mountain. In addition, the volcano has become an establishing shot in films, television series and programs set on the island of Tenerife.
Name and legends
Before the 1496 Spanish colonization of Tenerife, the native Guanches referred to a powerful figure living in the volcano, which carries light, power and the sun. El Pico del Teide is the modern Spanish name.Teide was a sacred mountain for the aboriginal Guanches, so it was considered a mythological mountain, as Mount Olympus was to the ancient Greeks. When going on to Teide during an eruption, it was customary for the Guanches to light bonfires to scare Guayota. Guayota is often represented as a black dog, accompanied by his host of demons.
The Guanches also believed that Teide held up the sky. Many hiding places found in the mountains contain the remains of stone tools and pottery. These have been interpreted as being ritual deposits to counter the influence of evil spirits, like those made by the Berbers of Kabylie. The Guanches believed the mountain to be the place that housed the forces of evil and the most evil figure, Guayota.
Guayota shares features similar to other powerful deities inhabiting volcanoes, such as the goddess Pele of Hawaiian mythology, who lives in the volcano Kīlauea and is regarded by the native Hawaiians as responsible for the eruptions of the volcano. The same was true for the ancient Greeks and Romans, who believed that Vulcano and Mount Etna were chimneys of the foundry of the fire god Hephaestus.
In 1492, when Christopher Columbus arrived at the island of Tenerife, his crew claimed to see flames coming from the highest mountain of the island.
Geography
Location
Teide is located on Tenerife, the largest island of the Canary Islands, situated in the Atlantic Ocean, northwest of the coast of Western Sahara. The volcano is located in a central position on the Tenerife island. Administratively, the Canary Islands are a Spanish autonomous community. Teide itself is located within the commune of La Orotava in the province of Santa Cruz de Tenerife.Topography
Before reliable measurements were available, Teide was considered by Europeans to be the highest mountain on Earth for a long time. With a height of, it is the highest point in Spain and the Atlantic Ocean. If it is measured from the ocean floor, it surpasses, making it the third highest volcanic structure in the world after Mauna Loa and Mauna Kea, both on the island of Hawaii.The formation of the mountain is marked by its long and complex volcanic history. It rests on the Las Cañadas caldera, an asymmetric depression in diameter in the form of a horseshoe which opens to the north. The floor of the caldera varies from in altitude, although its sides in the south rise to, the level of Mount Guajara. To the north, the slopes of Teide continue directly to the ocean, with a break in the slope at around. The volcano of Teide itself can be described as a volcanic cone in diameter at its base, with quite steep slopes, approximately 20 to 40° for a total volume of. The summit is marked by a small volcanic cone, about high, named El Pitón, which has a summit crater in diameter and deep. A secondary cone, named Pico Viejo emerges on the western slopes of the main peak; its crater is much larger, with a diameter of and a depth of. It rises to, but with a low prominence, not more than higher than the slopes of the main volcano. On the outside of these two main peaks, the relief Teide also has some smaller formations, of which the most notable are Roques Blancos, Pico Cabras, and Montaña Blanca, situated next to the base of Teide.
The slopes of Teide are covered in radial ravines. However, the majority of the ravines have been covered by recent lava flows, the Lavas Negras, in particular the northern part. The main ravines, with prominence around, are located on the south slope: from east to west, the Corredor Mario, Corredor La Corbata and Corredor La Bola.
Climate
Despite their proximity to the Sahara, the Canary Islands have a relatively temperate climate. The sunshine duration is very high due to Teide's subtropical latitude and proximity to the Azores high, and sees a very high UV index caused by the height of the peak. This sunshine of around 3,450 h per year is partially compensated by the Canary current, a relatively cold ocean current which makes the climate more temperate. The situation at the level of Teide and its caldera is very unlike the climate at its base. In effect, the climate of Tenerife is marked by an inversion layer around at an altitude of, isolating the high-altitude zones from ocean influences present at the lower altitudes. This leads to a more continental climate on Teide, with strong changes in temperature over the course of the day and in the course of the year.Humidity is also very affected by this inversion layer. The presence of the Azores high in the northwest of the Canaries in summer induces relatively constant winds blowing from the northeast to the southwest. These winds carry moisture across the Atlantic and deliver rain to the north of Tenerife, forming in particular a dense layer of clouds between of altitude. But the inversion layer also stops these clouds from rising, and the climate is thus very dry below the level of Teide. The precipitation in the caldera is thus less than 500 mm per year, the majority falling in the winter, and in total, around one third in the form of snow. Variation can be quite high from one year to the next. Meanwhile the peak of Teide is covered by wave clouds, forming the "hat of Teide" which was probably confused with signs of an eruption by sailors.
Geology
The Canary Islands
Teide is a stratovolcano created by the same forces which formed the Canary Islands. The islands are aligned relatively east to west, but continue to the northeast in a series of undersea mountains which are part of the same volcanic region as the Canary Islands. Dating indicates that the age of these islands changes from east to west, with the older islands and undersea mountains to the east and more recent ones to the west. This makes Fuerteventura and Lanzarote the oldest islands, from 20.2 Mya, and El Hierro the youngest, from 1.1 Mya. Counting the undersea mountains, Lars is the oldest, from 68 Mya. The Madeira islands, located not far to the north of the Canary islands and also volcanic, have many islands and undersea mountains aligned in the same general direction and with similar dates. This pattern is consistent with archipelagoes which have formed over a hotspot such as the Hawaiian Islands. However, there are many differences with Hawaii. First, the Hawaiian Islands are sinking rapidly into the ocean, forming atolls, yet the rate of subsidence is insignificant in the Canary Islands. If the Canary islands were sinking at the same rate as the Hawaiian islands, Teide would be actually below sea-level. But one of the most fundamental differences, and which lends doubt to the theory of a hotspot, is the fact that the volcanic activity is not constrained to the most recent island, but continues through all the islands in the chain. This has aroused an intense debate in the scientific community, which continues to a certain extent today. One hypothesis which allows reconciliation of these observations is the presence in the Earth's mantle of a convection cell which enters one part of the magma more towards the east, thus activating the old islands. According to this hypothesis, the magma would be also responsible for scattered volcanic activity to the northwest of the African continent to the south of Spain.Formation of Tenerife
The formation of Tenerife began a little less than 12 Mya. It started with the formation of a shield volcano centered not far from Teide itself, with volcanic activity which endured to around 8.9 Mya. The volcanic activity then stopped, and the volcano underwent some collapses in the process of erosion. One new shield volcano formed between 6 and 5 Mya, more to the west, in Teno then another in Anaga, to the east, between 4.9 and 3.9 Mya. Together, these three shield volcanoes represent 90% of the volume of Tenerife. The lavas are basalts, basic rocks and therefore very fluid, this explains the characteristic form of shield volcanoes.Around 3.5 Mya, after a pause of 5.5 million years, volcanic activity resumed to the level of the first shield volcano. This is the start of the rejuvenation phase, forming the volcano Las Cañadas. It was also in this period that the volcanic activity began in the rifts of the island, formed by radial fractures due to the thrust of magma in the central volcano. The eruptions of Las Cañadas were initially basic and fluid lavas, but they differentiated over time, which gave place to more explosive eruptions. Around 200,000 years ago, the peak of the volcano was swept away in a giant land slide to the north, forming the caldera of Las Cañadas. These massive landslides were quite frequent and were in part cased by the fractures of the rifts. Besides the caldera, the landslides were also responsible for the valley of La Orotava and Güímar.