geostrophic wind speed

geostrophic wind speed

geostrophic wind speed
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.
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.
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References in periodicals archive ?
7, the order of magnitude of the vertical change in geostrophic wind speed is consistent with the temperature gradient over the coastline.
We noticed that the rise and fall of temperature anomalies at 300 hPa has a pronounced effect not only on the 200 hPa zonal geostrophic wind speed anomalies but also on the wind direction.
20CR, on the other hand, seems to underestimate the wind speeds at 800 hPa: a rough calculation of the geostrophic wind speed in the region of the two stations with the strongest winds in Fig.
The wind forcing at a 10 m level was derived from geostrophic winds as recommended by Bumke and Hasse (1989): the geostrophic wind speed was multiplied by 0.6 and the direction turned by 15[degrees] to the left.
The most popular way consists in the use of geostrophic wind fields that are adjusted to the 10 m level by means of a simplified procedure in which the geostrophic wind speed (usually retrieved from the Swedish Meteorological and Hydrological Institute database) was multiplied by 0.6 and the direction turned 15[degrees] counter-clockwise (Bumke & Hasse 1989).
An approximation of the near-surface wind at the 10 m level, used as the input to the wave model, was calculated following a standard procedure in which the geostrophic wind speed was multiplied by 0.6 and the direction turned 15[degrees] anticlockwise (Bumke & Hasse 1989).