Abstract

Precise Positioning in GIS - Why Geodesy Matters
Track: Surveying
Authors: William Stone

The National Oceanic and Atmospheric Administration's National Geodetic Survey (NGS) is responsible for providing the nation's official fundamental positioning infrastructure, the National Spatial Reference System (NSRS). NSRS is the common and consistent spatial framework which allows geographic data from disparate sources to be successfully assimilated and analyzed. This presentation will provide an overview of NGS geodetic data, models, and tools, with a focus on offerings that are of particular interest to GIS practitioners. Fundamental aspects of geodesy and the importance of positioning accuracy will be discussed. Topics will include the status and planned developments of the NSRS, including future datums. Global Navigation Satellite System (GNSS)-related utilities, including the nationwide network of Continuously Operating Reference Stations (CORS) and the Online Positioning User Service (OPUS), play a major role in NSRS access, supporting centimeter-accurate positioning, and will be described.