Beginning in June 2005, the US-based National Oceanic and Atmospheric Administration (NOAA) will perform a general readjustment of the horizontal position and ellipsoidal heights in the National Spatial Reference System (NSRS) using high accuracy GPS data. The NSRS is a consistent national coordinate system that specifies latitude, longitude, height, scale and gravity throughout the nation. This data provides the foundation for transportation, communication, mapping, charting and a multitude of scientific and engineering applications. Using GPS data, the readjustment will improve accuracy and consistency of the NSRS and provide a local and network accuracy measure for each coordinate.
Managed by NOAA’s National Ocean Service’s National Geodetic Survey (NGS), the NSRS encompasses a network of permanently marked control points; a nationwide array of continuously operating GPS reference stations; up-to-date national shoreline data and a set of accurate models describing geophysical processes that affect spatial measurements such as plate velocities during an earthquake. NSRS control points aid in air navigation; provide data for coastal maps; and assist state and local highway planners with road construction.
“The readjustment is a part of NOAA’s continuing effort to provide accurate and reliable navigational products and services,” said retired Navy Vice Admiral Conrad C. Lautenbacher, Jr., Ph.D., under secretary of commerce for oceans and atmosphere and NOAA administrator.
The general readjustment is part of NOAA’s efforts to create a Global Earth Observation System of Systems (GOESS). GOESS will link existing technology in space, the ocean, and on land in order to provide a framework for systems, data and vital information so scientists and policy makers in different countries can design, implement and operate compatible observation systems.