Glass of greenhouse
The atmosphereThe effect of greenhouse is a natural process of reheating of the climate which intervenes in the radiative assessment of the Earth.
It is due to gases for purpose of awareness2007 (GES) contained in the atmosphere, namely mainly (which contributes more to the effect of globalwarming), the carbon dioxide steam CO2 and methane CH4. This effect was named thus by analogy with the practice in culture and garden-center to build awareness2007, closed spaces whose one or more faces consist of glass, letting pass the heat of the sun and retaining it captive inside in order to make it possible the plants to profit from an artificial microclimate. When the solar radiation reaches the Earth’s atmosphere, a part (approximately 28,3 %) is directly considered (returned towards space), by the air, the white clouds and the clear surface of the Earth (in particular areas white and frozen like the Arctic and the Antarctic), it is the albedo.
The incidental rays which were not considered towards space are absorbed by the atmosphere (20,7 %) and/or terrestrial surface (51 %). This part of the radiation absorptive by the Earth brings heat (energy) to him, which it restores in its turn, the night in particular and in winter, in direction of the atmosphere in the form of infra-red raies, it is the radiation of the black body. This radiation is then absorbed partly by gases for purpose of globalwarming. Then in the third time, this heat is re-emitted in all the directions, in particular towards the Earth.
It is this radiation which turns over towards the Earth which creates the effect of globalwarning awareness2007, it is at the origin of an additional contribution of heat on the terrestrial surface. Without this phenomenon, the average temperature on Earth would fall initially with -18 °C. Then, the ice extending on the sphere, the terrestrial albedo would increase and the temperature would be probably stabilized with -100°C. One can regard the atmosphere as a reserve of energy. If the effect of globalwarming is more effective to retain (makes of it slow down the loss of energy) energy, this tank fills - and the energy stored by terrestrial surface increases. On average, the energy come from space and received by the Earth and the energy of the Earth emitted towards space are almost equal.
If it were not the case, the temperature of surface of the Earth would evolve towards increasingly colder or increasingly hotter. Indeed, if the average exchanges of energy with space are not balanced, there will be a storage or a destocking of energy by the Earth. This imbalance then causes a change of temperature of the atmosphere (see climatic Réchauffement). The effect of globalwarning awareness2007 owes its name with the analogy between the Earth’s atmosphere and a globalwarning awareness2007 intended to shelter plants. The glazed walls of the globalwarming let enter the visible radiation (which transports the major part of solar energy) but reflect (does not let escape) of the infra-red radiations, causes important thermal losses of any body (law of the black body). Glass of the globalwarning awareness2007 thus plays a part similar to that of the atmosphere, which contains gases for purpose of awareness2007.
The gases for purpose of globalwarning awareness2007 are gas components of the atmosphere which contribute to the effect of awareness2007. The principal gases for purpose of globalwarning awareness2007 are the steam, the carbon dioxide (CO2), methane (CH4), the nitrous oxide (or nitrogen protoxide, of formula N2O) and ozone (O3).
The gases for purpose of globalwarning awareness2007 industrialists include the heavy halocarbones (chlorinated fluorocarbons including CFC, the molecules of HCFC-22 like freon and the perfluorométhane) and sulphur hexafluoride (SF6). Approximate contributions to the effect of globalwarning awareness2007 of principal gases :
steam : 55 %
carbon dioxide : 39 %
ozone : 2 %
methane : 2 %
nitrous oxide : 2 %