What mechanism describes how the Sun heats the Earth?

The mechanism through which the Sun heats the Earth is radiation. This process involves the transfer of energy in the form of electromagnetic waves, particularly in the form of infrared and visible light, directly from the Sun to the Earth's surface. Unlike conduction and convection, which require a medium (like air or water) for energy transfer, radiation can occur through the vacuum of space.

When solar radiation reaches the Earth, some of it is absorbed, thereby warming the surface and the atmosphere. This is fundamental to understanding climate and weather patterns, as it drives processes like evaporation and the circulation of air masses.

Conduction, convection, and advection are methods of heat transfer that rely on matter. Conduction transfers heat through direct contact between materials, convection involves the movement of fluids (liquid or gas) to carry heat, and advection is a horizontal movement of heat in fluids. These processes, while relevant to how heat is redistributed within the Earth’s atmosphere and oceans, do not describe the initial source of heat from the Sun.