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Greenhouse Effect

The greenhouse effect is an often misunderstood topic. Environmental concerns are rampant with the realization that the Earth's resources are limited and running out, as well as the worries about global warming and melting polar ice caps. While humankind is affecting the Earth's environment as a whole, the greenhouse effect would be in existence whether humans were or not.

Many planets in the solar system have a greenhouse effect naturally, including Earth. The atmospheres of planets and moons are composed of many different gases.

The combination of these have influence on how solar and infrared radiation affect the body itself, since the the atmosphere both absorbs and emits infrared radiation. In regards to the Earth, the atmosphere is made up mostly of water vapor, carbon dioxide and methane – referred to as greenhouse gases.

The Earth's atmosphere allows solar radiation through, which results in the sun heating the Earth's surface and providing the building blocks for plant and animal life. The Earth, in return, radiates heat back into the atmosphere where it is mostly absorbed rather than passed on into space. Because the atmosphere itself absorbs and emits radiation, this starts a cycle of trapping heat between the Earth and atmosphere, warming the planet and creating its friendly-to-human-life average surface temperature of 14° C (57° F). It is estimated that without an atmosphere and subsequently the greenhouse effect, the Earth's average surface temperature would be -18° C (-0.4° F) – not quite so livable to most of the species which inhabit the planet today.

The concern with the greenhouse effect is the increase of industrial activity by humans. This includes the burning of fossil fuels through which the majority of electricity is generated, increased deforestation worldwide (especially in the tropics), and increased cement usage which takes the place of absorbing and cooling soil and plants. With all of these factors stemming from the industrial revolution, the concentration of CO2 into the atmosphere has risen significantly, which also aids in the absorption and recycling of heat between the atmosphere and Earth. Because of this, the Earth's temperature is rising, triggering global warming issues like melting ice caps and threatening the delicate balance of life between the species that share the world.

Many people confuse the greenhouse effect to mean that it functions the same way a solar greenhouse for gardening works. This type of greenhouse is usually built of glass panels, allowing the heat from the sun in. The glass then traps the heat inside instead of allowing it to disperse into the surrounding area. The transfer of heat through fluids, gases and solids is called convection. A typical solar greenhouse works by preventing convection. The greenhouse effect, on the other hand, works by reducing radiation loss – meaning that the amount of heat radiated between the earth and atmosphere equalize.

The greenhouse effect is a talking point for individuals concerned about the environment. Some of the global efforts taken to reduce global warming have been focused on reducing the emission of CO2. By increasing energy efficiency and moving further towards green living, the demands on burning fossil fuels will decrease which will in turn decrease the CO2 emissions. Given enough time, this can reduce global warming and help the Earth return to an acceptable average temperature.