Projections and Grids

Having discussed the concept of geodesy in Chap. 3 , it is necessary to discuss the next step which includes ‘projections’ and ‘grids’. The spheroidal Earth model, for example, is mathematically perfectly suited to navigational calculations, but to physically display a portion of the Earth’s surface a projection is required. This chapter describes the conceptual underpinnings of projections in general, before introducing the projections most likely to be encountered at sea.