Tracing Temporal Information in an Automated Nautical Charting System

Nautical information is one example of spatial data with a strong temporal component. This paper describes the methods of temporal data representation to be used in a National Ocean Service (NOS) Automated Nautical Charting System (ANCS II). The system will be capable of tracing spatial change over time and of tracking cartographic and data-base procedures within the agency. The discussion describes a method of spatiotemporal representation within traditional geographic information systems (GIS) data structures, draws a distinction between information-oriented and production-oriented temporality, and identifies three fundamental elements of temporal metadata.