- Industry: Earth science
- Number of terms: 93452
- Number of blossaries: 0
- Company Profile:
Founded in 1941, the American Congress on Surveying and Mapping (ACSM) is an international association representing the interests of professionals in surveying, mapping and communicating spatial data relating to the Earth's surface. Today, ACSM's members include more than 7,000 surveyors, ...
The change in reading of an inertial surveying system with change in direction of motion of the system. Ideally, an inertial surveying system should indicate the same distance traveled per unit distance actually traveled, regardless of the direction of travel. In fact, some systems indicate a different distance when the direction of travel is north south than when the direction of travel is east-west.
Industry:Earth science
The amount (mass or weight) of water vapor present per unit amount (mass or weight) of the moist air.
Industry:Earth science
The gravity formula τ = τ<sub>e</sub> (1 + 0.005 279 0414 sin²φ + 0.000 023 2718 sin<sup>4</sup>φ + 0.000 000 1262 sin<sup>6</sup>φ + 0.000 000 0007 sin<sup>8</sup>φ) , in which τ<sub>e</sub> is 9.780 326 7715 m/s² and φ is the geodetic latitude. The numerical coefficients are derived from the constants in the set Geodetic Reference System 1980
Industry:Earth science
A correction made to values of gravity measured using a spring type gravimeter on a moving vehicle (usually a ship), to remove the errors caused when horizontal and vertical components of acceleration have equal periods and are out of phase. Corrections are calculated from the results of measurements on two horizontal accelerometers having their axes mutually perpendicular. They are small for low sea states and can be calculated with adequate accuracy for moderate sea-states.
Industry:Earth science
The equilibrium argument computed for the meridian of Greenwich.
Industry:Earth science
A Hayford template having the spacings of circles so proportioned (with respect to the scale of the accompanying map) that elevations and depths within each compartment formed by adjacent arcs can be averaged easily. The Hayford gravity template takes no account of the azimuths of the radii; all compartments bounded by a given pair of circles are the same size and shape. It is used for calculating topographic gravity-corrections.
Industry:Earth science
An arbitrary division of the Earth's surface into parts given designations without reference to longitude and latitude.
Industry:Earth science
Relating to elevation above a reference surface, usually the geoid. In a limited sense, hypsometric applies to those altitudes determined with a hypsometer.
Industry:Earth science
A method of solving Hansen's problem in resection which occurs when only two points of known location are available. An auxiliary point is established and angles measured from that point and from the unknown point to the two given points.
Industry:Earth science
