What Causes Global Warming ?

There is some recent research that is used to determine the contribution of the natural and the huma
n impact on global warming, as reported in the journal Skeptical Science. From the results of the study
were known to a number of issues of global warming.There is some recent research that is used to determine the contribution of the natural and the human impact on global warming, as reported in the journal Skeptical Science. 

All of these studies, using a variety of independent methods and the results proves that humans are the dominant cause of global warming over the past century, and especially over the past 50-65 years. As in the graph.Figure 1: Net human and nature contribute to the warming over the past 50-65 years according to Tett et al. (2000) (T00, dark blue), Meehl et al. 2004 (M04, red), Stone et al. 2007 (S07, green), and skin slim 2008 (LR08, purple), Huber and Knutti 2011 (HK11, light blue), and Gillett et al. 2012 (G12, orange).Impact of Various Global Current EffectsMost of the studies discussed below, occur in the same things that also appear as global temperatures rise, resulting in a dominant
effect. As is known, the human being through the gas emitters akitivitasnya so-called warm the Earth's temperature

increases the greenhouse effect. Besides solar activity adds to warm the earth even warmed up in the winter hemisphere.Another thing that is evident is volcanic activity generally cools the Earth's temperature for a certain time began releasing sulfate aerosols into the atmosphere, which blocks sunlight and reduces the solar radiation reaching the surface. However, unlike many greenhouse gases, aerosols are washed out of the atmosphere quickly, especially after 1-2 years. Thus the volcanic activity to temperature changes may occur in the long run when the conditions that increase or lower the earth's temperature memnpengaruhi.In addition to volcanic activity, human akitivitas emitting aerosol emissions (primarily sulfur dioxide [SO2]) also tend to cool the Earth's temperature. The difference is that unlike volcanoes, humans keep pumping aerosols into the atmosphere in large quantities by the burning
of fossil fuels and biomatter. It allows human aerosol emissions have a long term impact on the earth's temperature. However, because aerosols have a number of different effects (including directly by blocking sunlight, and indirectly by seeding clouds, which both can block sunlight and increase the greenhouse effect), the magnitude of the cooling effect is one of the biggest uncertainties in climate science rest .Other causes of warming is the El Nino Southern Oscillation (ENSO) is the storm cycle in the oceans that play a role alternated between phases of El Nino and La Nina. El Nino tends to move the heat from the ocean into the air, causing surface warming (but ocean cools), while the La Nina effect sebaliknyan. Several studies have examined whether ENSO has a long-term impact on global surface temperature. Because the cycle is likely to have little impact on long-term changes in temperature, with the La Nina effect is larger than El Nino.Other effects, is a gas that humans are excluded GHGs and SO2 are the two biggest and solar activity, volcanoes and ENSO makes a pretty dominant natural influences on global temperatures. Now let's see what that has affected global temperatures based on the scientific literature.Tett et al. (2000)In the report Tett et al. (2000) used 'optical detection methodology "with global climate model simulations to try and match the observational data.Tett et al. apply the model to determine global surface temperature from 1897 to 1997. Estimates of their best overall fit to measure global warming during this period. However, the warming that occurred from the period 1897-1947 did not receive great attention, and it was a new note in the period 1947 to 1997. Over a period of 50 years in their study (shown in dark blue in Figure 1), the amount of warming from human nature and greater than 100%. During the second period of 50 and 100 years, Tett et al estimate that natural factors have a net cooling effect slightly, and thus human factors have led to more than 100% for global warming.Meehl et al. (2004)Meehl et al. 2004 uses a similar approach to Tett et al., With a global climate model simulations using various combinations of the major factors that affect global temperatures, and compared the results of temperature data from 1890 to 2000. They found that natural factors can explain the warming problem from 1910 to 1940, but just can not explain global warming experienced since the mid-20th century.Meehl et al. estimates that about 80% of the global warming from 1890 to 2000 was due to human effects. Over the last 50 years in their study (1950-2000), combined with the cooling effect of the natural clean, and as such Tett et al., Meehl et al. man concludes that caused more than 100% during the period of global warming. So, for 25 years, almost 100% of the warming is due to humans.Stone et al. (2007)Stone et al, published their study in 2007. From the 2-year period of their study, studied 62 climate model simulation period 1940 to 2080 (the Dutch Meteorological Institute). These simulations utilized measurements of GHGs, volcanic aerosols, human aerosols, and solar activity from 1940 to 2005, similar to the Tett and Meehl studies discussed above, and then used in the future be used by the Intergovernmental Panel on Climate Change (IPCC) for measuring project global warming. During the 60 years of Stone et al, estimated that 100% human-induced warming. As with Stott, their model does not fit the data perfectly, even though they have the opposite result, despite warming is happening.In a second report, 2007, Stone et al update the results of their research and check the results of research in the 1901-2005 period. Over the full 104-year period, Stone et al. estimated that humans and nature each contribute about half of the global warming. They estimate that the sun and volcanic activity is responsible for 37% and 13% of the warming.Other studies such as Lean and Rind (2008), Stott et al. (2010), Huber and Knutti (2011) up by Gillett et al. (2012), almost the same. Which concluded that human and natural 100 percent as a contributor to global warming.Consensus, Humans Cause Global WarmingThe study, using a variety of different methods and approaches hsail quite extraordinary. Each study concluded that during the period of 100-150 years most recently explained, man is responsible for at least 50% of the heating, and most estimates put the human contribution between 75 and 90% during that period. For years (25-65 years), every study put the human contribution at least 98%, and most put it at well over 100%.Moreover, in each study the two biggest factors that influence global temperatures caused by humans: GHGs, followed by aerosol emissions. This is a dangerous situation because when cleaning the air and reducing SO2 emissions, the cooling effect will disappear, and it was a cause of greenhouse gases that cause global warming trends.There was a period of warming between 1910 and 1940 were primarily due to increased solar activity and volcanic activity is low, with some contribution by humans. However, since the mid-century, solar activity has been flat, there has been a moderate in volcanic activity and ENSO have little net impact on global temperatures. While GHGs continue to rise, and a dominant effect on global temperature changes.Various approaches are statistically and physically then arrived at the same conclusion: that humans are the dominant cause of global warming for a century, and especially over the past 50 years.