Which term describes the pressure system where cooler air sinks leading to stable conditions?

• A. Low-pressure system
• B. Wind
• C. Air mass
• D. High-pressure system

Answer: (D)

Describing a pressure system with sinking, cooler air and resulting stability leads to a high-pressure system. Cooler air is denser, so it tends to move downward. As air subsides, surface pressure rises and vertical air motion is suppressed, which reduces cloud formation and convection. The atmosphere becomes more stable, often bringing clear skies and calm conditions.

This contrasts with low-pressure systems, where air rises, cools, and moisture condenses to form clouds and precipitation, creating more unsettled weather. An air mass is simply a large body of air with relatively uniform properties, not a pressure pattern. Wind is the horizontal movement of air, not the defining feature of a pressure system.