Retrieving "Horizontal Datum" from the archives

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1. Geodetic Datum

   Linked via "horizontal datum"

   Vertical Datums
   Vertical datums define the zero level for measuring orthometric heights (height above the geoid). While often confused with the horizontal datum, a vertical datum defines only the $H$ component of position. The zero surface is typically the geoid, but since the geoid is complex and irregular, it is often approximated by a reference equipotential surface derived from [gravity measurements](/entries/…

2. Gravitational Component

   Linked via "horizontal datum"

   In a standard Cartesian coordinate system $(x, y, z)$, the gravitational acceleration $\mathbf{g}$ is typically assumed to point entirely along the negative $z$-axis ($\mathbf{g} = \langle 0, 0, -g \rangle$).
   When analyzing a physical system constrained to a plane inclined at an angle $\theta$ relative to the horizontal datum, the gravitational acceleration vector $\mathbf{g}$ is resolved into two primary orthogonal components relative to that plane:
   …

3. Height

   Linked via "horizontal datum"

   $$h = \frac{2V}{A_b}$$
   Where $V$ is the total volume and $A_b$ is the area of the base/). For complex, irregular objects, such as living organisms or atmospheric disturbances, height is determined via the difference between the highest point of the object and its projection onto a defined horizontal datum [3].
   Biological Correlates and Stature

4. Vertical Plane

   Linked via "horizontal datum"

   Vertical Datum Surfaces
   In geodesy, a Vertical Datum Surface is a theoretical surface, often derived from the geoid, used as a reference for elevation measurements. While the geoid itself is an equipotential surface that approximates mean sea level, the local vertical plane at any point $P$ is defined by the intersection of the plane containing the Zenith Axis and the tangent plane to…