The circulation of air in the atmosphere is primarily driven by **convection**. Convection occurs when warm air rises and cool air sinks, creating circulation patterns. This process is influenced by the unequal heating of the Earth's surface, which causes temperature and pressure differences in the atmosphere.
While **condensation**, **conduction**, and **evaporation** are important processes in the atmosphere, they do not directly drive air circulation in the same way that convection does.
- **Condensation** releases heat into the atmosphere, which can influence weather patterns but is a result of air movement rather than a driver of it.
- **Conduction** transfers heat between substances in contact but is not a significant factor in large-scale atmospheric movements.
- **Evaporation** contributes to the moisture content of the air and can influence local weather but is also not the primary mechanism for atmospheric circulation.
Thus, the key process responsible for driving atmospheric circulation is convection.