Availability Analysis of Mercator Projection in Nautical Charts' Compilation in Polar Regions

Abstract

Availability of Mercator projection in polar regions mainly suffers from gross scale error and only can be improved by control of scale error; methods of scale error control such as properly adjusting of standard parallels, appropriately defining and relaxing acceptable scale error thresholds together with adopting appropriate chart scales and sheet specifications are presented; appropriate acceptable scale error thresholds are discussed by referring to domestic and abroad chart compilation specifications and existing Russian polar nautical charts; availability of Mercator projection in latitudes of 75°~85°is analyzed on charts with various standard parallels, scale error thresholds and latitude ranges, the result indicates that Mecator projection still satisfies compiling requirements of nautical charts with commonly used scales and sheet specifications in latitudes between 75°and 85°.