La Palma

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This article is about one of the Canary Islands. For other similar names, see Palma (disambiguation).

La Palma, a Spanish island, is one of the Canary Islands in the Atlantic Ocean off Africa. It is located at 28°40′N 17°52′W.

Contents 1 Description 2 Government 3 Volcano 4 History 5 Water tunnels 6 Observatories 7 External links 7.1 La Palma island 7.2 Tsunami threat? 7.3 Telescopes

[edit] Description

La Palma has an area of 706 km². The total population is about 85,000, of which 18,000 (2003 data) live in the capital, Santa Cruz de la Palma and about 20,000 (2004 data) in Los Llanos de Aridane.

La Palma's geography is a result of the volcanic formation of the island. The highest peaks reach about 2400 m above sea level, and the foundation of the island reaches more than 3000 m below sea level. The northern part of La Palma is dominated by the Caldera de Taburiente, the largest erosion crater in the world, with a width of 9 km and a depth of 1500 m. It is surrounded by a ring of mountains ranging from 1600 m to 2400 m in height. Only the deep Barranco de las Angustias canyon leads into the inner area of the caldera which is a national park. It can be reached only by hiking. The outer slopes are cut by numerous gorges which run from 2000 m down to the sea. Today, only few of these carry water due to the water tunnels.

From the caldera to the south runs the ridge Cumbre Nueva. The southern part of La Palma is dominated by the Cumbre Vieja, a ridge formed by numerous volcanic cones built of ashes, providing a rather bizarre landscape. Several of these volcanoes are still active. The southern cape Punta de Fuencaliente, where the most recent volcanic activities took place, consists of lava and ashes.

La Palma is dominated by the colors blue, green and black. Blue is the surrounding ubiquitous sea. Green comes from the abundant plant life which is the most diverse in the Canary Islands. Black comes from the volcanic rocks that still fill the landscape, and from the numerous small beaches made of black sand.

[edit] Government

The island is part of the province of Santa Cruz de Tenerife.

The island capital is Santa Cruz de la Palma. The other major city on the island is Los Llanos.

The island is divided into 14 municipalities:

Barlovento Breña Alta Breña Baja Fuencaliente Garafía Los Llanos de Aridane El Paso

Puntagorda Puntallana San Andrés y Sauces Santa Cruz de la Palma Tazacorte Tijarafe Villa de Mazo

[edit] Volcano

The island was formed as a seamount by the volcanic activities like all of the Canary Islands. La Palma is the most active volcano of the Canary Islands and was formed 3 million years ago. It rises 3500 m from the seafloor to the sea surface and reaches a height of 2426 m above sea level. 500,000 years ago the primary volcano Taburiente collapsed with a giant landslide which formed the Caldera de Taburiente. The known historic eruptions are:

• 1470-1492 Montaña Quemada
• 1585 Tajuya near El Paso
• 1646 Volcán San Martin
• 1677 Volcán San Antonio
• 1712 El Charco
• 1949 Volcán San Juan, Duraznero, Hoyo Negro
• 1971 Volcán Teneguía

During the 1949 eruption of the Cumbre Vieja a small amount of surface subsidence occurred close to the small volcano vent. In a highly disputed BBC Horizon program, broadcast on October 12, 2000, two scientists used this surface anomaly to claim that half of La Palma slipped four meters downwards into the Atlantic Ocean.^[1][2] They believe that this process was driven by the pressure caused by the rising magma heating and vaporizing water trapped within the structure of the island. They projected that during a future eruption, the western half of the island, weighing perhaps 500 billion tonnes, could slide into the ocean. This could generate a giant wave known as a megatsunami around 900m high in the region of the islands. The wave would fan out across the Atlantic and strike the Caribbean and the eastern American seaboard some eight hours later with a wave possibly 90 m or more high causing massive devastation along the coastlines.

There have been a number of reports disputing these claims. The Tsunami Society published a statement in 2003 stating that they "would like to halt the scaremongering from these unfounded reports."^[3] Another Web site by a resident of La Palma gives a point-by-point rebuttal of the major points raised by the BBC program.^[4] The major points raised in these reports include:

• The conclusion that half of Cumbre Vieja dropped 4m during the 1949 eruption is erroneous, and contradicted by physical evidence.
• No evidence was sought or shown that there is a fault line separating a "block" of La Palma from the other half.
• Physical evidence shows a 4km long line in the rock, but the models assumed a 25km line, for which no physical evidence was given. Further, there is no evidence shown that the 4km long line extends beyond the surface.
• There has never been an Atlantic megatsunami.

[edit] History

The Canary Islands had been settled by the native Canarians called Guanches whose origin is still controversial. They had a neolithic culture divided into several clans led by chiefs. Their name for La Palma was Benahoare. The main remnants of this culture are their cave dwellings, enigmatic petroglyphs and paved stone paths through the mountains. After the Spanish occupation of La Palma, the native Canarians vanished by either being killed, sold into slavery or by assimilating into the Spanish population.

It is probable that the Canary Islands were known to the Phoenicians and the Greeks. The Genoese navigator Lancelotto Malocello reached the archipelago in 1312 and remained for two decades until expelled by a native uprising. In 1404 the Spaniards began the conquest of the islands. Though the first landing on La Palma was in 1405, it took until 1493 and several bloody battles until the last resistance of the natives was broken. The conqueror of La Palma was Alonso Fernández de Lugo, who defeated Tanausu, the last king on the island. He ruled the area known as Acero (Caldera de Taburiente). Tanausu was ambushed after agreeing to a truce arranged by Fernández de Lugo and Juan de Palma, a Guanche who had converted to Christianity and who was a relative of Tanausu.

For the next two centuries, settlements on La Palma became rich as the island served as a trading post on the way to the New World. La Palma received immigrants from Castile, Portugal, Majorca, Flanders, and Catalonia.

[edit] Water tunnels

The most famous structures of La Palma are the water tunnels which carry the water from sources in the mountains to cities, villages and farms (mainly banana plantations and vineyards). La Palma receives plenty of water due to the clouds brought by the Trade Winds. The tunnels were carved into the rocks over centuries. One can follow some of the tunnels by hiking, a popular activity for tourists. The tour to the Marcos y Corderos waterfall and springs is also popular

[edit] Observatories

Main article: Roque de los Muchachos Observatory

Due to the location of the island and the height of its mountains, some 2400 m above sea level, a number of international observatories have been built on the Roque de los Muchachos. The particular geographical position and climate cause clouds to form between 1000 m and 2000 m, usually leaving the observatories with a clear sky. Often, the view from the top of the volcano is a sea of clouds covering the eastern part of the island. Telescopes at the observatory include:

• The Isaac Newton Group of Telescopes (ING) operates three telescopes: the 4.2 m William Herschel Telescope, the 2.5 m Isaac Newton Telescope and the 1 m Jacobus Kapteyn Telescope.
• The 2.5 m Nordic Optical Telescope (NOT).
• The 1 m Swedish Solar Telescope (SST) operated by the Institute for Solar Physics.
• The 0.45 m Dutch Open Telescope (DOT).
• A 0.6 m optical telescope.
• The Carlsberg Meridian Telescope (CMT).
• The 1.2 m Mercator Telescope.
• The 2 m Liverpool Telescope.
• The 10.4 m Gran Telescopio Canarias (under construction).
• The 3.6 m Telescopio Nazionale Galileo (TNG).
• The 17 m MAGIC Telescope, an air shower Cherenkov telescope for observing high energy gamma rays

The DOT and the SST have been specifically built to study the Sun.

[edit] External links

Wikimedia Commons has media related to: La Palma

[edit] La Palma island

• La Palma -picture wikimedia commons
• La Palma, Canary Islands - data and lots of pictures
• The Island of La Palma
• Pictures at Flickr of Isla Bonita
• La Palma Gallery - Diashows, Landscapes, Impressions
• Watch from above La Palma points of interests and add your preferred ones (map provided by Google)

[edit] Tsunami threat?

• Scientists warn of massive wave
• Tidal wave threat 'over-hyped'
• Contra-evidence

[edit] Telescopes

• Observatorio del Roque de los Muchachos
• Isaac Newton Group of Telescopes
• Nordic Optical Telescope
• Dutch Open Telescope
• Carlsberg Meridian Telescope
• The MAGIC Telescope Home Page

Islands and provinces of the Canary Islands

Islands of the Canary Islands Main :  Fuerteventura · Gran Canaria · La Gomera · El Hierro · Lanzarote · La Palma · Tenerife Other :  Alegranza · Graciosa · Lobos · Montaña Clara · Roque del Este · Roque del Oeste

Provinces of the Canary Islands Las Palmas · Santa Cruz de Tenerife