Nauru is a small, oval-shaped island in the western Pacific Ocean, 42 km (26 mi.) south of the Equator. It is about 0.1 times the size of Washington, DC. The island is surrounded by a coral reef, exposed at low tide and dotted with pinnacles. The reef is bound seaward by deep water, and inside by a sandy beach. The presence of the reef has prevented the establishment of a seaport, although sixteen artificial canals have been made in the reef to allow small boats to access the island. A 150–300 m (about 500–1000 ft.) wide fertile coastal strip lies landward from the beach. Coral cliffs surround the central plateau, which is known on the island as Topside. The highest point of the plateau is 65 m (213 ft.) above sea level. The only fertile areas are the narrow coastal belt, where coconut palms flourish. The land surrounding Buada Lagoon supports bananas, pineapples; vegetable, pandanus trees and indigenous hardwoods such as the tomano tree are cultivated. The population of the island is concentrated in this coastal belt and around Buada Lago.
Nauru was one of three great phosphate rock islands in the Pacific Ocean (the others are Banaba (Ocean Island) in Kiribati and Makatea in French Polynesia); however, the phosphate reserves are nearly depleted. Phosphate mining in the central plateau has left a barren terrain of jagged limestone pinnacles up to 15 m (49 ft.) high. A century of mining has stripped and devastated four-fifths of the land area. Mining has also had an impact on the surrounding Exclusive Economic Zone with 40% of marine life considered to have been killed by silt and phosphate run off.Republic of Nauru. 1999. Climate Change Response Under the United Nations Framework Convention on Climate Change URL accessed 2006-05-03.
There are limited natural fresh water resources on Nauru. Roof storage tanks collect rainwater, but islanders are mostly dependent on a single, aging desalination plant. Nauru's climate is hot and extremely humid year-round, because of the proximity of the land to the Equator and the ocean. The island is affected by monsoonal rains between November and February. Annual rainfall is highly variable and influenced by the El Niño-Southern Oscillation, with several recorded droughts. The temperature ranges between 26 and 35 °C (79 and 95 °F) during the day and between 25 and 28 °C (77 and 82 °F) at night. As an island nation, Nauru may be vulnerable to climate and sea level change, but to what degree is difficult to predict; at least 80% of the land area of Nauru is well elevated, but this area will be uninhabitable until the phosphate mining rehabilitation program is implemented.Republic of Nauru. 1999. Climate Change Response Under the United Nations Framework Convention on Climate Change URL Accessed 2006-05-03
There are only sixty recorded vascular plant species native to the island, none of which are endemic. Coconut farming, mining and introduced species have caused serious disturbance to the native vegetation. There are no native land mammals; there are native birds, including the endemic Nauru Reed Warbler, insects and land crabs. The Polynesian Rat, cats, dogs, pigs and chickens have been introduced to the island.