geostrophic wind

The geostrophic wind is a theoretical wind that arises from a balance between two forces: the pressure-gradient force and the Coriolis force. The pressure-gradient force pushes air from areas of high pressure to areas of low pressure. However, because the Earth rotates, an apparent force called the Coriolis force deflects this motion.123

In the Northern Hemisphere, the Coriolis force deflects the wind to the right, causing it to blow parallel to lines of equal pressure (isobars) with low pressure on the left. In the Southern Hemisphere, the deflection is to the left, with low pressure on the right. This geostrophic balance is a useful concept in meteorology for understanding large-scale wind patterns, especially where direct wind observations are scarce. While real winds are also affected by friction, particularly near the surface, the geostrophic wind provides a fundamental approximation.24