What is the term for the transfer of heat by a current?
diffusion
conduction
radiation
convection
Convection is the transfer of heat by a current. Convection happens in a liquid or a gas. Air near the ground is warmed by heat radiating from Earth's surface. The warm air is less dense, so it rises. As it rises, it cools. The cool air is dense, so it sinks to the surface. This creates a convection current ( Figure below ). Convection is the most important way that heat travels in the atmosphere.