ATAFU ATOLL, TOKELAU, SOUTHERN PACIFIC OCEAN
Atafu Atoll is around 8 kilometres wide and is the smallest of the three atolls and one island which make up the Tokelau Islands group located in the southern Pacific Ocean. Tokelau is a territory of New Zealand; the combined land area of the three coral atolls is 10 km² and the islands have a population of approximately 1,400. Most of the world’s coral atolls are in the Pacific Ocean.
The area of light grey dots in the northwestern corner of the atoll is a village, the primary settlement on Atafu. The ring shape of the atoll is the result of coral reefs building up around a former volcanic island. The original volcano has subsided beneath the water surface over hundreds of millions of years and has left behind the fringing reefs and a central lagoon with submerged coral reefs. Through erosion and soil development on the surfaces of the fringing reefs, vegetation has taken root. Atafu Atoll’s approximate elevation is only two metres above the tidal high-water level; this makes the atoll vulnerable to tropical cyclones and potential sea level rise.
The image was taken by the Expedition 18 crew on January 6, 2009, with a Nikon D2Xs digital camera fitted with an 800 mm lens, and is provided by the ISS Crew Earth Observations experiment and the Image Science & Analysis Laboratory, Johnson Space Center.