What atmospheric phenomenon is primarily driven by warm air rising?

The phenomenon driven by warm air rising is convection. In the atmosphere, convection is the process where warm air becomes less dense and rises, while cooler air, which is denser, sinks. This continuous cycle creates a convection current, which is responsible for various weather patterns and helps in the distribution of heat in the atmosphere.

In addition to this primary mechanism, convection plays a crucial role in the formation of clouds, thunderstorms, and other weather systems. It serves to transport heat from the Earth's surface into the upper atmosphere, contributing significantly to atmospheric circulation.

The other concepts, such as compression, radiation, and advection, represent different physical processes that do not primarily involve the rising of warm air as their main driver. Compression deals with the increase in pressure of air without necessarily involving temperature changes due to rising air. Radiation refers to the transfer of energy through electromagnetic waves and is not dependent on air movement. Advection describes the horizontal movement of air and does not focus on the vertical rising motion caused by heat. Thus, convection is the accurate answer as it specifically represents the process related to warm air rising.