Mechanical turbulence is caused by what?

Mechanical turbulence is caused by what?

• A. Surface obstructions such as bluffs, hills, mountains, buildings, and trees.
• B. Jet streams aloft.
• C. Humidity changes.
• D. Warm moist air rising gently.

Answer: (A)

Mechanical turbulence is produced when air flow near the surface is disrupted by what sits on the ground—the roughness of the terrain and man-made structures. Obstacles like bluffs, hills, mountains, buildings, and trees break the smooth wind into swirling eddies and gusts. This creates irregular, gusty motion close to the ground and in low-level air, which is exactly what pilots feel as mechanical turbulence. Jet streams aloft cause turbulence from wind shear at higher altitudes, not from surface disturbances. Humidity changes don’t create those surface eddies, and warm moist air rising gently points to convective processes rather than mechanical disruption of the surface wind.

Mechanical turbulence is produced when air flow near the surface is disrupted by what sits on the ground—the roughness of the terrain and man-made structures. Obstacles like bluffs, hills, mountains, buildings, and trees break the smooth wind into swirling eddies and gusts. This creates irregular, gusty motion close to the ground and in low-level air, which is exactly what pilots feel as mechanical turbulence.

Jet streams aloft cause turbulence from wind shear at higher altitudes, not from surface disturbances. Humidity changes don’t create those surface eddies, and warm moist air rising gently points to convective processes rather than mechanical disruption of the surface wind.