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"Global climate change needs global
action now. The alarm bells ought to be ringing in every capital of the world"
John Gummer, British Environment Secretary
"The
greenhouse effect refers to the change in the
thermal equilibrium temperature of a planet or moon by the presence of an
atmosphere
containing gas that absorbs and emits
infrared
radiation.[1]
Greenhouse gases, which include water vapor, carbon dioxide and methane,
warm the atmosphere by efficiently absorbing thermal infrared radiation emitted
by the Earth’s
surface, by the atmosphere itself, and by
clouds. As a result of its warmth, the atmosphere also radiates thermal
infrared in all directions, including downward to the Earth’s surface. Thus,
greenhouse gases trap heat within the surface-troposphere system.[2][3][4][5]
This mechanism is fundamentally different from the mechanism of an actual
greenhouse, which instead isolates air inside the structure so that heat is
not lost by
convection and
conduction, as discussed below. The greenhouse effect was discovered by
Joseph Fourier in 1824, first reliably experimented on by
John
Tyndall in the year 1858 and first reported quantitatively by
Svante Arrhenius in his 1896 paper Source:
Wikipedia
