Physics B.2 The Greenhouse Effect

Emissivity

A measure of a surface’s ability to emit thermal radiation compared to an ideal black body at the same temperature.

Albedo

The measure of the reflectivity of a surface, defined as the ratio of total scattered power to total incident power.

Solar constant

The amount of solar electromagnetic radiation received per unit area per unit time at the top of Earth’s atmosphere.

Greenhouse gases

Gases in Earth’s atmosphere that absorb and emit infrared radiation, contributing to the greenhouse effect.

Greenhouse effect

The process by which greenhouse gases in Earth’s atmosphere trap heat, leading to an increase in the planet’s surface temperature.