As a result of friction, how does the surface wind speed compare to the geostrophic wind?

• A. Faster
• B. Slower
• C. Equal
• D. Unpredictable

Answer: (B)

The surface wind speed is generally slower than the geostrophic wind due to the effects of friction. Geostrophic winds are calculated based on the balance of pressure gradients and the Coriolis effect, typically occurring at higher altitudes where frictional forces are negligible. However, near the surface, friction plays a significant role by opposing the wind's motion and reducing its speed.

This friction arises from the interaction of wind with the Earth's surface, which includes obstacles like terrain, buildings, and various types of vegetation. The roughness of the surface creates turbulence and alters wind flow, causing the wind speed to decrease as it approaches the ground. As a result, you can expect the winds at the surface to be slower compared to those calculated using geostrophic principles, leading to the conclusion that surface wind speed is indeed slower than the geostrophic wind.