Dynamic height
Encyclopedia
Dynamic height is a way of specifying the height of a point above a reference, as opposed to orthometric height
or normal height
.
Dynamic height is constant if one follows the same gravity potential as they move from place to place. Because of variations in gravity, surfaces having a constant difference in dynamic height may be closer or further apart in various places. Dynamic heights are usually chosen so that zero corresponds to the geoid.
When optical leveling is done, the path corresponds closely to following a value of dynamic height horizontally, but to orthometric height for vertical changes measured on the leveling rod. Thus small corrections must be applied to field measurements to obtain the orthometric height
usually used in engineering. US National Geodetic Survey data sheets give both dynamic and orthometric values.
Orthometric height
The orthometric height is the distance H along a line of force from a given point P at the physical surface of an object to the geoid.Orthometric heights are what are usually used in the US for ordinary engineering work. Values for measured points can be obtained from the National Geodetic Survey...
or normal height
Normal height
Normal heights are heights above sea level, one of several types of height which are all computed slightly differently. Alternatives are: orthometric heights and dynamic heights....
.
Dynamic height is constant if one follows the same gravity potential as they move from place to place. Because of variations in gravity, surfaces having a constant difference in dynamic height may be closer or further apart in various places. Dynamic heights are usually chosen so that zero corresponds to the geoid.
When optical leveling is done, the path corresponds closely to following a value of dynamic height horizontally, but to orthometric height for vertical changes measured on the leveling rod. Thus small corrections must be applied to field measurements to obtain the orthometric height
Orthometric height
The orthometric height is the distance H along a line of force from a given point P at the physical surface of an object to the geoid.Orthometric heights are what are usually used in the US for ordinary engineering work. Values for measured points can be obtained from the National Geodetic Survey...
usually used in engineering. US National Geodetic Survey data sheets give both dynamic and orthometric values.