Tag Archives: canada
CGVD2013, Part 2
Above picture: This color contour map shows the difference between CGVD2013 and NAVD 88, especially of interest to those who work on projects along the U.S./Canada border. In part 1 of this series in xyHt’s October issue, Canada’s new vertical datum is introduced—CGVD2013— with an overview of past Canadian datums, directions during the current transition...
Canada’s New Vertical Datum: CGVD2013
Geodesy Editor’s Note: The study of Earth’s gravity field is one of the most important aspects of physical geodesy. While seldom mentioned in land surveying text books or discussed at local surveying, mapping, or GIS conferences, it is nonetheless one of the most important issues that geospatial experts deal with on a daily basis. Changing...
Future of Determining Elevation
A frank discussion of the different heights used in surveying, what’s inside a geoid model, and how geoid model data is used within GNSS software to produce elevations. Certainly most geospatial professionals who have used Global Navigation Satellite Systems (GNSS) within their surveying workflows have come across the term “geoid model” before. But who actually knows...
