Unlike winds aloft, which blow nearly parallel to the isobars, surface winds generally cross the isobars. Explain what causes this difference

Question

What will be an ideal response?

Answer 1

Friction acts to slow air movement and, as a consequence, alters wind direction. Above the friction layer, the pressure–gradient force and Coriolis effect work together to direct the flow of air. Under these conditions, the pressure–gradient force causes air to start moving across the isobars. Eventually, the Coriolis effect will balance the pressure–gradient force, and the wind will blow parallel to the isobars—these are upper-air winds (geostrophic winds).