The Republic of Nauru lies at 0.5oS and 167oE. It is a raised atoll with an area of 21 km2 and a maximum elevation of 71 m. The island is surrounded by a fringing coral reef between 120 and 300 m wide. The reef drops away sharply on the seaward edge to a depth of about 4000 m. The land area consists of a narrow coastal plain, known locally as Bottomside, ranging from 100–300 m wide, which encicircles a limestone escarpment rising some 30 m to a central plateau, known as Topside.
Topside consists of a matrix of coral-limestone pinnacles and limestone outcrops, and covers an area of 1,600 ha (over 70% of the island). It has been the focus of phosphate mining for over 80 years. Relative elevations on Topside vary generally between 20 and 45 m above sea-level. The highest point on the island is Command Ridge (71 m).
Global Climate Change Alliances (GCCA)