What causes earth's surface to heat up?

The Earth's surface is heated by incoming shortwave radiation from the sun, which heats the Earth and then releases longwave radiation, which warms the atmosphere and is reflected by the greenhouse effect. This is why the Greenhouse effect and global warming are about the atmosphere rather than the surface of the Earth.

The Earth's surface heats up primarily due to the greenhouse effect, which is caused by certain gases in the atmosphere trapping heat from the sun. These gases, such as carbon dioxide, methane, and water vapor, allow sunlight to penetrate the atmosphere but prevent some of the resulting heat from escaping back into space. Additionally, factors such as solar radiation, albedo (reflectivity of the Earth's surface), and human activities, such as deforestation and the burning of fossil fuels, contribute to the heating of the Earth's surface.