geostrophic wind speed


geostrophic wind speed
The speed of a geostrophic wind calculated from the pressure gradient, air density, rotational velocity of the earth, and latitude. The calculation ignores the curvature of the wind’s path. A geostrophic wind is proportional to the pressure gradient or inversely proportional to the distance between the isobars.
Winds exist because of horizontal and vertical pressure gradient so atmospheric motion can be deduced from isobaric surface charts etc. If the horizontal pressure gradient force is exactly balanced in magnitude by Coriolis effect accelerations of the air will be relatively small and a geostrophic wind will flow horizontally at a constant speed proportional to the isobaric spacing gradient, perpendicular to the two opposing forces and parallel to straight isobars. Thus geostrophic wind speed is proportional to the pressure gradient. The closer the isobars, the higher will be geostrophic wind speed.

Aviation dictionary. 2014.

Look at other dictionaries:

  • geostrophic wind speed — /dʒiəˈstɒfɪk/ (say jeeuh stofik) noun the speed of the wind calculated from the pressure gradient, the air density, the rotational velocity of the earth, and the latitude, but neglecting the curvature of the path of the air …   Australian English dictionary

  • Geostrophic wind — The geostrophic wind is the theoretical wind that would result from an exact balance between the Coriolis force and the pressure gradient force. This condition is called geostrophic balance. The geostrophic wind is directed parallel to isobars… …   Wikipedia

  • geostrophic wind — noun a) Meteorology. A wind whose direction and speed are determined by a balance of the horizontal pressure gradient force and the force due to the earths rotation to the left in the northern hemisphere and to the right in the southern… …   Wiktionary

  • geostrophic wind — noun : a wind whose direction and speed are determined by a balance of the pressure gradient force and the force due to the earth s rotation * * * a wind whose velocity and direction are mathematically defined by the balanced relationship of the… …   Useful english dictionary

  • geostrophic wind — That horizontal wind velocity for which the Coriolis acceleration exactly balances the horizontal pressure or gradient force. Pressure gradient force causes air parcel to accelerate. Coriolis begins deflecting air to the right. Coriolis increases …   Aviation dictionary

  • gradient wind speed — noun the speed of the wind calculated as for geostrophic wind speed, but taking into account the curvature of the path of the air …   Australian English dictionary

  • Wind gradient — In common usage, wind gradient, more specifically wind speed gradientcite book | last = Hadlock | first = Charles | title = Mathematical Modeling in the Environment | publisher = Mathematical Association of America | location = Washington | year …   Wikipedia

  • geostrophic scale — A scale expressed on transparent material and placed across the isobars to measure the geostrophic wind. See also geostrophic wind speed. Geostrophic wind scale for use with one standard parallel at 60°N …   Aviation dictionary

  • Wind shear — Wind shear, sometimes referred to as windshear or wind gradient, is a difference in wind speed and direction over a relatively short distance in the atmosphere. Wind shear can be broken down into vertical and horizontal components, with… …   Wikipedia

  • Wind — For other uses, see Wind (disambiguation). Wind, from the …   Wikipedia