National Geodetic Survey Announces National Adjustment of 2011 Project

As part of the National Geodetic Survey's (NGS) continuing efforts to improve the National Spatial Reference System (NSRS), on May 27, NGS was pleased to announce the National Adjustment of 2011 (NA2011) project. The NSRS is the consistent reference system defining latitude, longitude, height, scale, gravity, and orientation throughout the United States and its territories. NGS maintains and provides access to the NSRS, the foundation for the nation's transportation, mapping, and charting infrastructure, as well as a multitude of other scientific and engineering applications.

The NA2011 Project will yield updated North American Datum of 1983 (NAD 83) coordinates on approximately 80,000 NGS passive control marks positioned using Global Navigation Satellite System (GNSS) technology. The new adjustment will ensure passive GNSS marks are optimally aligned with the NGS Continuously Operating Reference Station (CORS) network. The NA2011 Project is being done now, because NGS has determined a new set of NAD 83 CORS coordinates. Additional information on the CORS-based realization of NAD 83 is available on the NGS Summary of the Reanalysis of GPS Data (beta) website.

Our goal is to complete the NA2011 Project by the end of calendar year 2011. More information on the NA2011 Project is provided in a comprehensive list of Frequently Asked Questions (FAQs) on the NGS website. The FAQs are part of an NA2011 Project web page currently under development. For more information, contact Michael Dennis.