Geography of Saint Helena
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Saint Helena consists of a number of islands, in the South Atlantic Ocean, about mid-way between South America and Africa, at the geographic coordinates 15°56′S 5°42′W / 15.933°S 5.7°W. St Helena occupies a land area of 420 square kilometres, which includes Saint Helena (122 km²), Ascension, and the island group of Tristan da Cunha, which consists of Tristan da Cunha Island, Gough Island, Inaccessible Island, and the three Nightingale Islands. There are 60 km of coastline in St Helena. In terms of maritime claims, St Helena has an exclusive fishing zone of 200 nautical miles, and a territorial sea of twelve nautical miles.
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[edit] Physical Geography
[edit] Climate
The climate of Saint Helena island can be described as tropical, marine and mild, tempered by trade winds. Similarly, the climate of Tristan da Cunha is marine, mild and also tempered by trade winds, although the climate is temperate in nature.
[edit] Terrain
Saint Helena has a rugged, volcanic terrain, with small scattered plateaus and plains, with the largest area of level ground on the island being Prosperous Bay Plain in the eastern arid area. The other islands of the group have a volcanic origin. The highest point is Queen Mary's Peak, on Tristan da Cunha, at 2,060 m, while the lowest point is the Atlantic Ocean, with an elevation of 0 m.
A natural hazard on Tristan da Cunha is active volcanism.
[edit] Geological Features
The Barn is a capping of younger lavas upon weaker rocks. The Barn features cliffs on the side that faces the sea. It overlooks the pyroclasts and weak flows of Turk's Cap Valley to the south.[1]
Taking their names from the story of Lot in the Book of Genesis, "Lot" and "Lot's Wife" are two solitary pillars of rock topping two valleys near Sandy Bay. The pillars are phonolitic intrusions, which are more resistant to erosion than surrounding volcanic features which have, in time, eroded away. [2] {
[edit] Natural resources
Saint Helena possesses fish as a main natural resource. Land use in the island group is divided between arable land (with 12.9% of the area given to this) and other uses, which occupy the remaining 87.1%.
[edit] Ecology
Saint Helena harbours at least 40 species of plants unknown anywhere else in the world, and Ascension is a breeding ground for sea turtles and sooty terns.
[edit] References
This article incorporates public domain material from websites or documents of the CIA World Factbook.
