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Future energy demand and supply

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Figure 11 The origin of the natural greenhouse effect shown schematically. Incoming short-wavelength energy from the Sun is absorbed by atmospheric oxygen, ozone and water vapour but most visible wavelengths reach the Earth's surface. Outgoing longer wavelengths radiated from the Earth are largely absorbed by atmospheric gases, causing a heating effect. Note: The upwards sequence of gases does not represent any vertical zonation. Pale yellow indicates where wavelengths are absorbed, or are neither emitted by the Sun nor the Earth's surface. Each gas has a number of absorption bands, but, of course, these only result in absorption of the wavelengths emitted by the Sun and Earth.

 3.1 Fossil-fuel burning and global warming