Climate:
Saint Helena: tropical marine; mild, tempered by trade winds
Ascension Island: tropical marine; mild, semi-arid
Tristan da Cunha: temperate marine; mild, tempered by trade winds
(tends to be cooler than Saint Helena)
Terrain:
the islands of this group result from volcanic activity associated
with the Atlantic Mid-Ocean Ridge
Saint Helena: rugged, volcanic; small scattered plateaus and plains
Ascension: surface covered by lava flows and cinder cones of 44
dormant volcanoes; ground rises to the east
Tristan da Cunha: sheer cliffs line the coastline of the nearly
circular island; the flanks of the central volcanic peak are deeply
dissected; narrow coastal plain lies between The Peak and the
coastal cliffs
Elevation extremes:
lowest point: Atlantic Ocean 0 m
highest point: Queen Mary's Peak on Tristan da Cunha 2,062 m; Green
Mountain on Ascension Island 859 m; Mount Actaeon on Saint Helena
Island 818 m
Natural resources:
fish, lobster
Land use:
arable land: 12.9%
permanent crops: 0%
other: 87.1% (2005)
Irrigated land:
NA
Natural hazards:
active volcanism on Tristan da Cunha, last eruption in 1961
Environment - current issues:
NA
Geography - note:
Saint Helena harbors at least 40 species of plants unknown anywhere
else in the world; Ascension is a breeding ground for sea turtles
and sooty terns; Queen Mary's Peak on Tristan da Cunha is the
highest island mountain in the South Atlantic and a prominent
landmark on the sea lanes around southern Africa
People Saint Helena