Impact of North American Datum of 1983

Abstract

The new adjustment of the North American Datum of 1983 (NAD 83) is now in its 10th year. To understand the necessity for the new adjustment, a review of the problems encountered with the existing NAD 27 network must be examined. The status of the project is important to the users of geodetic control data because they must begin to plan for the transition from NAD 27 to NAD 83. The problems of the transition are understood, and the National Geodetic Survey (NGS) is already developing information to assist users in adapting to the changes. These changes will involve new coordinate values and a new coordinate system which will affect all levels of control surveying and mapping, including the U.S. Geological Survey's topographic map series.