key term - Greenhouse effect

Definition

The greenhouse effect is the process by which certain gases in Earth's atmosphere trap heat, preventing it from escaping into space. This natural phenomenon maintains Earth's temperature at a level suitable for life.

5 Must Know Facts For Your Next Test

1. Greenhouse gases include carbon dioxide ($CO_2$), methane ($CH_4$), and water vapor ($H_2O$).
2. Radiation from the sun enters Earth’s atmosphere, gets absorbed by the surface, and is re-emitted as infrared radiation.
3. Greenhouse gases absorb and re-emit infrared radiation, trapping heat in the atmosphere.
4. The greenhouse effect is essential for maintaining Earth’s average temperature around 15°C (59°F).
5. An enhanced greenhouse effect, caused by increased levels of greenhouse gases due to human activities, leads to global warming.

Review Questions

Related terms

Infrared Radiation:

A type of electromagnetic radiation with wavelengths longer than visible light but shorter than microwaves; it is emitted by all objects based on their temperature.

$CO_2$: $CO_2$ or carbon dioxide is a colorless gas that is a major contributor to the greenhouse effect when present in high concentrations in the atmosphere.

Global Warming: The long-term increase in Earth's average surface temperature due to human activities that increase concentrations of greenhouse gases.