The average temperature on Earth is mesaured through a balance of the different forms of solar and terrestrial radiation. Solar radiation is often called “short” radiation, because the frequency of the radiation is relatively high, and the relatively short wavelength in the vicinity of the visible part of the electromagnetic spectrum. Radiation from the earth, on the other hand, is often referred to as “long” radiation, because the frequencies are relatively small and relatively long wavelength, somewhere in the infrared range. -The shift to the bottom of solar energy is usually in watts per square meter. The energy of the total solar radiation at the top of the atmosphere of the Earth (the so-called “solar constant”) amounts to approximately 1,366 watts per square meter per year. Setting for the fact that only half the surface of the planet is the sun’s rays at a certain time, the average solar radiation from the surface 342 watts per square meter per year.

The amount of solar radiation absorbed on Earth is only a small fraction of the total solar radiation into the atmosphere. Sun value per 100 units incident, about 30 units found in the room by one of the clouds, air, deliberation or regions on earth. This capacity for reflection, the albedo of the planet Earth, and it should not be set in the time since the magnitude and spatial distribution of the training of considerations, such as clouds and ice, may change. The 70 units of the sun’s rays, which are not reflected May be absorbed through the air, the clouds or the surface. In the absence of other complications to the thermodynamic equilibrium of the earth’s surface and the atmosphere must radiate these 70 locations in space. Soil temperature at the surface (and the lower layer of the atmosphere, especially in contact with the surface) is the size of the emission of radiation from the law by Stefan-Boltzmann.

Land of the energy budget is by greenhouse gases. Traces of gases with certain chemical properties of the so-called greenhouse gases, especially carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O)-absorb a portion of the infrared radiation by the Earth’s surface. Because of this recording, a fraction of the original 70 employees not directly to the escape. Because greenhouse gases exactly the same amount of radiation they absorb and also because this radiation is spent in all directions (which, as far down as shown above), the net effect of absorption by greenhouse gases is an increase in the total amount of radiation emitted down on the earth’s surface and lower atmosphere. To maintain the equilibrium of the earth’s surface and lower atmosphere emits more radiation than the 70 employees. Therefore, the temperature must be higher. This process is not quite the same as in a real, the greenhouse effect, but the effect is similar to an end. The presence of greenhouse gases in the atmosphere leads to a warming of the surface and lower atmosphere (and cooling earlier in the atmosphere) in comparison to what was expected in the absence of greenhouse gas.

It is important to distinguish between “natural” or background, the greenhouse gases of “enhanced” greenhouse effect associated with the activities of humans. The natural greenhouse effect is with the properties of the surface of natural warming of the atmosphere of the earth, particularly the water vapor, carbon dioxide and methane. The existence of this effect is by all scientists. In fact, in his absence, the mean temperature of the earth from about 33 ° C (59 degrees F) cooler than today, and the earth would be frozen and probably planet uninhabitable. What was controversial is the so-called greenhouse effect, with an increase in the concentration of greenhouse gases from human activities. Especially by the burning of fossil fuels increases the concentration of main greenhouse gases in the atmosphere, and these higher concentrations have the potential heat up the atmosphere by several degrees.