Geostrophic wind

The geostrophic wind ( gr γῆ, Earth '& στροφή, turn ', ' curve ', ' rotation ' = about wind that blows with the Earth's rotation ) is a simplified physical model of wind meteorology based on the geostrophy or geostrophic adjustment. It is based on wind observations in the northern hemisphere. The special feature is that the model of the geostrophic wind, the isobars ( lines of equal air pressure ) can be seen as a straight line. This model is except in meteorology also used in navigation, as the Single Heading Flight.

Geostrophic wind

The geostrophic wind is created by an opposing balance of pressure gradient force (drift from the high to the low pressure area ) and Coriolis force. It occurs in reality is only in larger tropospheric height, particularly pronounced than Jetstream.

Ageostrophischer Wind

In the planetary boundary layer of the atmosphere - the Peplosphäre (lower 1.5 to 2 miles) - the wind is slowed down by the bottom friction. Here he does not blow parallel to isobars, but rather towards the lower air pressure, which fill the low pressure areas after a few days. The deflection of the wind is doing way more to the ground and takes as seen from above, the shape of a spiral, the so-called Ekman spiral on (cf. Ekman spiral in the field of ocean current ). If the wind, as described here, by friction or other influences ( so-called ageostrophic components, such as the vorticity ) affected, it is called ageostrophic winds.

Geostrophic wind

Geostrophic wind

Ageostrophischer Wind

See also