Which type of atmosphere resists upward motion?

The stable atmosphere is characterized by a tendency to resist upward motion, which affects how air parcels behave within the atmosphere. In a stable atmosphere, air is cooler and denser than the surrounding air at higher altitudes. This density difference creates a condition where rising air parcels quickly cool and become denser than their surroundings, causing them to sink back down rather than continue rising.

Conversely, an unstable atmosphere encourages upward motion. In such conditions, warm air rises more easily because it is less dense than the cooler air around it, leading to the potential development of strong vertical currents, such as those observed in thunderstorms.

Dynamic and variable atmospheres are less defined concepts in this context; they do not directly specify the resistance to upward motion or have a clear connection to the stability of the air. Thus, the stable atmosphere is the appropriate choice since it clearly defines the resistance to upward motion in the atmospheric behavior.