The greenhouse effect on the Earth is a combination of certain conditions that was first named because it was presumably similar to the atmosphere of a greenhouse. While it may be easier to understand when the two are compared, it isn’t exactly the same principle.
The Greenhouse Effect was identified in 1824 by Joseph Fourier, a French mathematician and physicist who worked with the properties of heat transfer. It was further studied by John Tyndall, a British physicist, in 1858.
Water vapor, carbon dioxide, nitrous oxide and gases such as methane, trap energy from the sun, and they warm the Earth much as we would warm a greenhouse. Without these gases in the atmosphere the Earth would be a lot cooler.
The main contributors to the greenhouse effect are water vapor, which makes up about 30-70 % , carbon dioxide at 10-25%, methane at 4-10 %, and ozone, at 3-7 %.
Once sunlight reaches the earth, much of the energy is absorbed by water, land and the rest of the biosphere, however, some of it remains in the atmosphere causing heat.
Unlike the heating of the earth, in a greenhouse, the light from the sun enters through the glass or polycarbonate, which keeps the heat from escaping by insulation. The Earth and greenhouses are both similar in that they limit the rate of thermal energy leaving the system, but they differ in the method that the heat is retained.
The greenhouse prevents interior heat from being lost back through the structure by the use of the plastic, polycarbonate or glass panels. The earth is heated because the gases in the atmosphere absorb the outgoing energy and return it back towards the earth.
In the greenhouse warm air remains confined, but on the earth, warm air rises and combines with cooler air.
In recent years, the effect of people on the earth and their contribution to the greenhouse effect has been evaluated extensively. Carbon emissions are the biggest factor in human activity that has been considered a problem. This has been an especially major concern due to fossil fuel burning, and vehicle emissions.
CO2 data has been recorded for many years from ice core data, and it does fluctuate over the centuries, however, the most recent studies have shown that it has risen from 313 ppm in 1960, to 389 ppm in 2010.
Environmentalists are concerned that at this rate of increase, there may be a definite change soon in the overall climate of the earth.
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