These two attributes-comparatively small land area and small population size-have inevitably led to the marginalization of the Pacific islands region in many global datasets. The number of people occupying Pacific islands is approximately 10.8 million, some 0.15 % of the earth’s population. In the past, perceptions of uniformity or emptiness within the Pacific encouraged generalization (Köppen 1936 Ward 1989) and even today, when the diversity of its natural environment is almost universally acknowledged, there remains a need for informed generalization for particular purposes (e.g., Ellison 2009 Dickinson 2001 Mueller-Dombois and Fosberg 1998 Neall and Trewick 2008 Richardson and Richardson 1986).Ĭompared to most inhabited parts of the earth’s surface, the Pacific Basin bounded by continental margins is different in land areas that are comparatively small and isolated from one another and from the Basin rim land totals around 0.34 % of the area of the Pacific Basin. Spanning almost one-third of the earth’s surface, the Pacific presents a daunting challenge to anyone seeking to generalize about it, whether this refers to its geology, its ocean, its islands, or the peoples who inhabit them. It may also be used in spatial assessments of second-order phenomena associated with the islands, such as their vulnerability to various disasters, coastal erosion, or ocean pollution as well as human populations, built infrastructure and natural resources.Īs the management of human systems has become more globalized, so the need to effectively capture environmental diversity at global and regional scales has increased. It is anticipated the classification will become the basis for more focused investigation of spatial variability of the climate and ocean setting as well as the biological attributes of Pacific islands. With exception of the few continental islands, the distribution of island types is broadly interpretable from the proximity of island-forming processes. Rationale for the spatial distributions of the various island attributes is drawn from the available literature and canvassed in the text. Continental islands, 18 of the 1779 islands examined, are not included in maps showing the distribution of island attributes and types. Most common are reef islands (36 %) and volcanic high islands (31 %), whereas the least common are composite low islands (1 %). These attributes yielded eight island types: volcanic high and low islands limestone high and low islands composite high and low islands reef (including all unconsolidated) islands and continental islands. It is intended to be valid at a regional scale and based on two attributes: five types of lithology (volcanic, limestone, composite, continental, surficial) and a distinction between high and low islands. The principal aim of the classification is to assess the spatial diversity of the geologic and geomorphic attributes of Pacific islands. Reefs lacking islands and short-lived (<20 years) transient islands are not included. An earth-science-based classification of islands within the Pacific Basin resulted from the preparation of a database describing the location, area, and type of 1779 islands, where island type is determined as a function of the prevailing lithology and maximum elevation of each island, with an island defined as a discrete landmass composed of a contiguous land area ≥1 ha (0.01 km 2) above mean high-water level.
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