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pressure-gradient force

pressure-gradient force (PGF)
1. The force acting on air that is due to pressure differences. Horizontal variations in pressure create a tendency for movement from higher to lower pressure. This is only one component of the forces acting on the actual wind, however, so air does not normally flow at right angles across the isobars. Other forces are associated with the rotation of the Earth beneath the moving wind, and with a centrifugal force where the path of the wind is curved. In practice, the air moves nearly parallel to the isobars above the friction layer. See also Coriolis effect and geostrophic wind.

2. The force acting on a water mass which is due to pressure differences over distance. Horizontal variations in pressure create a tendency for movement from higher to lower pressure areas. See also geostrophic current.

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"pressure-gradient force." A Dictionary of Ecology. . Encyclopedia.com. 29 Apr. 2017 <http://www.encyclopedia.com>.

"pressure-gradient force." A Dictionary of Ecology. . Encyclopedia.com. (April 29, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/pressure-gradient-force-0

"pressure-gradient force." A Dictionary of Ecology. . Retrieved April 29, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/pressure-gradient-force-0

pressure-gradient force

pressure-gradient force (PGF)
1.. The force acting on air due to pressure differences. Horizontal variations in pressure create a tendency for movement from higher to lower pressure: this is only one component of the forces acting on the actual wind, though, so air does not normally flow at right angles across the isobars. Other forces are associated with the rotation of the Earth underneath the moving wind, and with a centrifugal force where the path of the wind is curved. In practice the air moves nearly along the isobars above the friction layer. See also CORIOLIS FORCE; and GEOSTROPHIC WIND.

2.. The force acting on a water mass due to pressure differences over distance. Horizontal variations in pressure create a tendency for movement from higher to lower pressure areas. See also GEOSTROPHIC CURRENT.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"pressure-gradient force." A Dictionary of Earth Sciences. . Encyclopedia.com. 29 Apr. 2017 <http://www.encyclopedia.com>.

"pressure-gradient force." A Dictionary of Earth Sciences. . Encyclopedia.com. (April 29, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/pressure-gradient-force

"pressure-gradient force." A Dictionary of Earth Sciences. . Retrieved April 29, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/pressure-gradient-force