Science Mission Directorate. National Aeronautics and Space Administration. Electromagnetic Spectrum Series Series Homepage. Infrared Waves. Reflected Near-Infrared. Visible Light. Ultraviolet Waves. Earth's Radiation Budget. Diagram of the Electromagnetic Spectrum. Ozone O3 is also a relatively minor greenhouse gas because it is found in relatively low concentrations in the troposphere the lowest layer of the atmosphere. In the troposphere, it is produced by a combination of pollutants — mostly hydrocarbons and nitrogen oxide compounds.
In the s, John Tyndall, an Irish scientist who was fascinated by the growth and formation of glaciers, wanted to test his ideas explaining how Earth maintained a fairly constant temperature.
He began a series of experiments to measure the amount of radiant heat infrared radiation that certain gases could absorb and transmit. Tyndall found that water vapor and carbon dioxide were good absorbers and emitters of infrared radiation. The relative importance of a greenhouse gas depends on its abundance in Earth's atmosphere and how much the gas can absorb specific wavelengths of energy.
An effective absorber of infrared radiation has a broader absorption profile, which means that it can absorb a wider spectrum of wavelengths. The sun's ultraviolet wavelengths are strongly absorbed by ozone in the stratosphere. The sun's visible wavelengths of radiation pass easily through the atmosphere and reach Earth. Some of this energy is emitted back from the Earth's surface in the form of infrared radiation. Water vapor, carbon dioxide, methane, and other trace gases in Earth's atmosphere absorb the longer wavelengths of outgoing infrared radiation from Earth's surface.
These gases then emit the infrared radiation in all directions, both outward toward space and downward toward Earth. This process creates a second source of radiation to warm to surface — visible radiation from the sun and infrared radiation from the atmosphere — which causes Earth to be warmer than it otherwise would be. Some of this energy is emitted from Earth's surface back into space in the form of infrared radiation. Much of this infrared radiation does not reach space, however, because it is absorbed by greenhouse gases in atmosphere, and is then emitted as infrared radiation back toward the Earth's surface.
This process is known as the greenhouse effect. These include :. The greenhouse effect is influenced by human activities, and this is what is causing the climate to change.
But too much of it is not good either:. It is easy to see that this has increased dramatically in the past 70 years. In the next chapter, we will look at the greenhouse gases in more detail and learn how to compare them. Learn About Community. Greenhouse Effect: How does Climate Change work? The Sun. The Earth's core. Without greenhouse gases, our planet would be a frozen ball of ice. In recent years, however, excess emissions of carbon dioxide and other greenhouse gases from human activities mostly burning fossil fuels have begun to warm Earth's climate at a problematic rate.
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