Since knowledge is known about the climate, scientists have studied that appeared in Earth’s climate is always changing. From the study of ice time in the past show that weather can change by itself, and changed drastically. What is it? Meteor fall? Variations hot sun? Mountain cloud burst which caused the smoke? Changes in wind direction due to changes in the structure of the Earth faces the sea and flow? Or because the composition of the air change? Or the other?
Until the 19th century on the new, the study on the climate began to know about the actual gas in the atmosphere, referred to as greenhouse gases, which can affect climate on Earth. What are greenhouse gases?
In fact that was known as’ greenhouse gases’, is an effect, in which molecules in the atmosphere we provide as a greenhouse effect. Greenhouse gases alone, should be the natural effect is to maintain the surface temperature on Earth is normal temperature, about 30 ° C, or if not, then of course there will be no life in the face of this Earth.
In the years around 1820, Fourier discovered that the father is the atmosphere can be penetrated (permeable) by the sun light into the surface of Earth, but not all the light that emanated to the surface of the Earth that can be reflected, infra-red radiation, which should disappear trapped, thus Earth and the atmosphere trap heat (the principle greenhouse).
Thirty years later, Mr. Tyndall found that types of gases trap heat that is mainly carbon-dioxide and water vapor, and finally the molecule is named as a greenhouse gas, as we know it now. Arrhenius and then show that if the concentration of carbon dioxide-duplicated, the increase in surface temperature to be very significant.
Since the discovery of Fourier, Tyndall and Arrhenius, the scientists understand how the greenhouse gases absorb radiation, allows to make a better calculation for the concentration of greenhouse gases and increasing temperatures. If the concentration of carbon-dioxide duplicated, then the temperature can be increased up to 1 ° C.
However, the atmosphere is not simply a model calculation, the fact is the increase of temperature can be more than 1 ° C due to factors such as, a course, change the number of clouds, reflection of heat between different land and sea, changes in moisture contents in the air, the surface changes Earth, either because of land clearing, changes in the surface, or causes the other, because the natural and human acts. Evidence indicates that there is, the atmosphere that have become more heat, the atmosphere with the store more moisture, and store more heat, warming strengthening of the standard calculation.
Since 2001, studies on global climate dynamics indicate that most do not, the world has experienced more warming of 3 ° C since the pre-industrial era, if only it can press the concentration of greenhouse gases so stable at 430 ppm CO2e (ppm = part per million = one million per ekivalen CO2 – which states the ratio of the amount of molecular gas CO2 per one million air dry). That, since 1900, the Earth has experienced warming of 0.7 ° C.
Then, if the heating occurs, as it is called, which was then known as global warming, What is a natural phenomenon that is not avoided? Or there is a reason that more evident, so it became ‘popular’ like this now? Was it because Al Gore with the film “An Inconvenient Truth” that global warming popularize? Of course, not simply that.
Need to work together internationally to be able to say that the man who became the main cause of the occurrence of global warming. Reports IPCC (Intergovernmental Panel on Climate Change) in 2007, shows that the average global human activity since the 1750 cause of warming. Changes in abundance of greenhouse gases and aerosols due to sun radiation and the entire surface of the Earth affect the climate system’s energy balance. In magnitude as Radiative Forcing as a means of measuring whether the global climate be hot or cold (red represent positive values or cause to be more warm, and of the blue), then found that the result of human activity which is the main supporter of a global warming (image. 1)
Seen that the image of carbon-dioxide gas is the main contributor glass. From pre-industrial period is equal to 280 ppm to be 379 ppm in 2005. This number exceeds the number of study natural climate change from the past (paleoklimatologi), where 650 thousand during the year was increasing from only 180-300 ppm. Especially in the last decade (1995-2005), the increased concentration of carbon dioxide-largest pertahun (1.9 ppm per year), far greater than the measurement of the atmosphere in 1960, (1.4 ppm per year), despite there are still variations per year year.
Source, especially the increased concentration of carbon-dioxide is the use of fossil fuels, plus the influence of land surface changes (land clearing, logging, forest burning, mencairnya es). Increasing the concentration metana (CH4), from 715 ppb (part per billion = one-per-billion) in pre-industrial era to be 1732 ppb in the early 1990s, and 1774 in 2005. This number exceeds the natural changes during the 650 thousand years (320 – 790 ppb). Metana the main source of agriculture and increase the use of fossil fuels. Concentration of nitrous oxide-oxide (N2O) from 270 ppb – 319 ppb in 2005. Emissions as well as the other contributor, is the main source of human agrikultural. Combination three main components will be the largest contributor to global warming.
Contribute antropogenik on aerosols (sulphate, organic carbon, black carbon, nitrate and dust) to provide cool effects, but the effect is not dominant compared to the occurrence of heating, in addition to the calculation of uncertainty is very large. Similarly with the ozone changes due to chemical processes troposper formation of ozone (nitrogen oxide, carbon monoxide and hydrocarbons) contribute to global warming. Ability sun light reflection (albedo), the effects of changes in the surface of Earth and deposisi aerosol black carbon from the snow, causing changes that vary from cooling to heating. Ray emission changes from the Sun (solar irradiance) did not give a large contribution to the global warming.
Thus, it can be understood that the people who have a role for their own fate, because of global warming resulted from the act itself human. So what the impact of Global Warming for life? Flow time prediction and the impact of science perspective can be read on the second part this paper.
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