Lijit Ad Wijit

Buy Sell Today

Affiliate Banner

Access Ad

Elite Ad

The cause of global warming

The cause of global warming

1.Effect greenhouse

Any source of energy found in the Earth comes from the sun. Most of the energy in the form of short wave radiation, including visible light. When this energy surface of the Earth arrived, he changed from light into heat that warm the Earth. Surface of the Earth, will absorb some heat and toss the rest back. Part of this substantial heat infra red radiation wave length to outer space. However, some heat remains trapped in the earth's atmosphere due

menumpuknya the amount of greenhouse gases, among others, water vapor, carbon dioxide, and metana the wave radiation into this trap. Gases absorb this radiation and reflect back waves that emanated Earth and consequently heat is stored in the surface of the Earth. These conditions continue to occur so that resulted in an average temperature of the earth continues to increase yearly.

Gas-gas functions as a gas in a glass house. With the increasing concentration of gases in the atmosphere, the more heat is trapped underneath.

Greenhouse effect of this is needed by all living creatures on earth, because without it, this planet will be very cool. With an average temperature of 15 ° C (59 ° F), the earth actually has more hot 33 ° C (59 ° F) from the temperaturnya, if there is no greenhouse effect the earth temperature is -18 ° C so that ice will cover the entire surface of the Earth. Akan but vice versa, when these gases in the atmosphere has been excessive, will cause global warming.

2.Effek feedback

Anasir causes of global warming is also influenced by various processes bait behind the dihasilkannya. For example is the evaporation of water. In the case of heating due to increased gas-greenhouse gases such as CO2, warming in the first place will cause many more water vapor to the atmosphere. Because the water vapor itself is a greenhouse gas, warming will continue and increase the amount of moisture in the air to reach an equilibrium concentration of water vapor. Greenhouse gases that dihasilkannya larger than CO2 gas caused by its own. (Although this feedback to improve the absolute water contents in the air, the air relative humidity is almost constant or even slightly decreased because the air becomes menghangat). This feedback resulted in only slowly as CO2 has a long age in the atmosphere.

feedback effect due to the influence of clouds is becoming the object of research at this time. When viewed from below, clouds will reflect back infra red radiation to the surface, so that will increase the heating effect. Conversely when viewed from above, the clouds will reflect sun rays and infra red radiation to the sky, increasing the cooling effect. What is its net result in heating or cooling depending on some details, such as certain types of altitude and cloud. Details represented in this difficult climate models, such as the cloud is very small when compared with the distance between the boundaries komputasional in climate models (about 125 to 500 km for the model used in the IPCC reports to view Four). Nevertheless, cloud feedback is on the ranking of two when compared with the water vapor feedback and is considered positive (the heating) in all models used in IPCC reports to The Four.
important feedback the other is the loss of the ability reflective (albedo) by the ice. When global temperatures increase, ice near the poles are in the melt with the increased speed. Along with these melelehnya ice, water or land will be open underneath. Both land and water have the ability to reflect light a little more when compared to the ice, and consequently will absorb more sun radiation. This will increase the warming and cause more ice to melt, into a cycle of development.

Positive feedback due terlepasnya CO2 and CH4 from melunaknya frozen soil (permafrost) are other mechanisms that contribute to warming . In addition, the ice melt will also release the CH4 also cause a positive feedback.

The ability to absorb carbon to the oceans will also be reduced if he menghangat, this is caused by menurunya level nutrien on mesopelagic zone limiting the growth fitoplankton of the diatom, which is a low carbon filtering. 

3.Variasi Sun

The hypothesis that the variation of the Sun, with a possibility strengthened by feedback from the clouds , can contribute in the heating at this time. The difference between this mechanism with the warming due to greenhouse gases is increasing activity Matahari akan heat stratosfer the greenhouse gases will freeze stratosfer. Cooling the bottom of most stratosfer not have been observed since 1960,  that will not happen if Sun activities to be the main contributor to warming at this time. (Ozone layer depletion can also provide cooling effect but dilution occurs starting the end of 1970s.) Sun Phenomena variation combined with volcanic activity may have to give the effect of heating the pre-industrial period until 1950, and the cooling effect since 1950 . 

There are some results of research that states that the Sun's contribution may have been ignored in global warming. Two ilmuan from Duke University mengestimasikan that Sun may have contributed to 45-50% increase in average temperature during the global period 1900-2000, and about 25-35% between 1980 and 2000. Stott and colleagues revealed that the climate model made the guidelines at this time to over-estimate the effects of gas-greenhouse gases compared with the influence of sun they also revealed that the cooling effect of dust vulkanik and sulphate aerosols have also been deemed frivolous. Nevertheless, they concluded that even with the increasing sensitivity the influence of climate on the sun though, most of the warming that occurred in the last decades is caused by the gas-greenhouse gases.

In 2006, a team ilmuan from the United States, Germany and Switzerland stated that they found no increase in levels of "information" from the sun in the last thousand years. Sun cycle only a small increase of about 0.07% in the level of "information" during the last 30 years. This effect is too small to contribute to global pemansan. A study by Lockwood and Fröhlich found that there is no relationship between global warming with sun variations since 1985, through the variation of output variations in the sun and cosmic rays.

Lijit Ad Wijit

Access Elite

Access eLite's

Powered by Access eLite's