Which term best describes Buys Ballot's Law in meteorology, the relationship between wind direction and pressure in the Northern Hemisphere?

• A. Friction
• B. Coriolis effect
• C. Buys Ballot's Law
• D. Pressure gradient force

Answer: (C)

Buys Ballot's Law describes how wind direction relates to the location of pressure centers in the Northern Hemisphere. When you stand with your back to the wind, the low-pressure center will be on your left and the high-pressure center on your right. This rule arises from the combination of the pressure gradient force pushing air from high to low pressure and the Coriolis effect deflecting winds to the right in the Northern Hemisphere, causing the wind to cross isobars in a way that makes the low-pressure area sit to the observer’s left. Near the surface, friction can slightly modify the exact direction, but the left-side rule remains a practical guide for locating a low-pressure center from wind direction. The other terms describe forces or effects involved in wind creation or behavior, not this specific left-right relationship.