National Center for Geographic Information and Analysis

Methods of analysis on a spherical earth are reviewed. The techniques are relevant to both point data and data from field variables (functions that are continuous and everywheredefined on the sphere). The background mathematics and statistics applicable to spherical surfaces are presented. The probability density function (pdf) for nearest neighbor distance on a sphere generated by a Poisson process is derived. The use of spherical analysis in conjunction with global geographic information systems is detailed. This review is relevant to researchers in geography, global change and related fields who study processes at global scales.