How do you communicate and report height measurements to clients and stakeholders?

2 Height systems

Height systems are sets of rules and conventions that define how height measurements are made and referenced. There are different height systems for different regions and countries, depending on the geoid or ellipsoid model they use, and the datum or origin point they choose. For example, in the United States, the most common height system is the North American Vertical Datum of 1988 (NAVD 88), which uses the Geodetic Reference System 1980 (GRS 80) ellipsoid and a datum point in Quebec, Canada. In the United Kingdom, the most common height system is the Ordnance Datum Newlyn (ODN), which uses the mean sea level at Newlyn, Cornwall, as the datum point.

3 Height conversion

Height conversion is the process of transforming height measurements from one system to another. This is necessary when you need to compare or combine height data from different sources or regions, or when you need to use a different height system for a specific purpose. For example, if you have orthometric height data from NAVD 88, but you need to use ellipsoidal height data for a global positioning system (GPS) application, you need to convert the orthometric height to ellipsoidal height using a geoid model. There are various tools and software available for height conversion, such as the National Geodetic Survey's online geoid calculator.

4 Height accuracy

Height accuracy is the degree of closeness of a height measurement to its true value. Height accuracy depends on several factors, such as the method and equipment used for height measurement, the quality and resolution of the reference surface, the errors and uncertainties in the height system, and the environmental conditions and disturbances. Height accuracy can be expressed as a standard deviation, a confidence interval, or a tolerance limit. For example, a height accuracy of 0.1 meter at 95% confidence means that there is a 95% chance that the true height value is within 0.1 meter of the measured value.

5 Height presentation

Height presentation is a method of displaying and reporting height data in maps and reports. To ensure the information is clear, consistent, and informative for the audience and purpose, there are several best practices to follow. These include using appropriate units and symbols for height measurements, such as meters, feet, or inches; using appropriate scales and contours for height maps; using appropriate formats and standards for height reports; and utilizing visual aids and graphics to explain the data. By following these best practices, you can communicate and report height measurements effectively to clients and stakeholders.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?