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Traverse PC provides support for HAD 83 Epoch 2010.00 in its CRS files.
As a rule, the NAD zone parameters have not changed from the previous epoch (2005.00), which TPC called NAD83 (CONUS). However, starting with TPC V16.2, the NAD 83 zones are now contained in the following files.
NAD 83 (2011) - CONterminous United States (CONUS), Alaska and US territories in the Caribbean
NAD 83 (PA11) - Hawaii, American Samoa, the Marshall Islands and other US territories residing on the Pacific Plate
NAD 83 (MA11) - this file is not currently included with TPC
The following is from http://www.ngs.noaa.gov/web/surveys/NA2011/
As part of continuing efforts to improve the NSRS, on June 30, 2012, NGS completed the National Adjustment of 2011 Project. This project was a nationwide adjustment of NGS "passive" control (physical marks that can be occupied with survey equipment, such as brass disk bench marks) positioned using Global Navigation Satellite System (GNSS) technology. The adjustment was constrained to current North American Datum of 1983 (NAD 83) latitude, longitude, and ellipsoid heights of NGS Continuously Operating Reference Stations (CORS). The CORS network is an "active" control system consisting of permanently mounted GNSS antennas, and it is the geometric foundation of the NSRS. Constraining the adjustment to the CORS optimally aligned the GNSS passive control with the active control, providing a unified reference frame to serve the nation's geometric positioning needs.
Current NAD 83 CORS coordinates were determined by re-processing all CORS data collected from January 1994 to April 2011 in the NGS initial Multi-Year CORS Solution (MYCS1) project. The resulting CORS coordinates were published by NGS in September, 2011, and constitute a new realization referred to as NAD 83(2011), NAD 83(PA11), and NAD 83(MA11) Epoch 2010.00. The realization name has two parts: the datum tag in parentheses after NAD 83, and the epoch date in decimal years. The datum tag refers to the year the realization was completed (2011) and the tectonic plate to which the coordinates are referenced (2011 refers to the North America plate, PA11 to the Pacific plate, and MA11 to the Mariana plate). The epoch date indicates that the published coordinates represent the location of the control stations on January 1, 2010 -- an important consideration in tectonically active areas (such as the western U.S.). In this way, the CORS coordinates (and thus the passive marks constrained to the CORS) are consistent across both space and time. Additional information on the MYCS1 realization of NAD 83 is available on the NGS CORS Coordinates web page.
Additional information: http://www.ngs.noaa.gov/CORS/coords.shtml
Related Topics
Coordinate Reference Systems
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