Mayhem
Banned
http://en.wikipedia.org/wiki/Global_warming
http://en.wikipedia.org/wiki/Global_warming#Discourse_about_global_warming
Line plot of global mean land-ocean temperature index, 1880 to present (2013), with the base period 1951-1980. The black line is the annual mean and the red line is the five-year running mean. The green bars show uncertainty estimates. [This is an update of Fig. 1A in Hansen et al. (2006).] The graph shows an overall long-term warming trend. In the 1890s, the global temperature anomaly was on average slightly below -0.3 °C, with an error range of roughly -0.2 and -0.4 °C. In the 1940s, the global temperature anomaly was on average slightly below +0.1 °C, with an error range of roughly 0.0 and +0.15 °C. In the 2000s, the global temperature anomaly was on average slightly below +0.6 °C, with an error range of roughly +0.6 and +0.5 °C.
Scientific understanding of the cause of global warming has been increasing. In its fourth assessment (AR4 2007) of the relevant scientific literature, the Intergovernmental Panel on Climate Change (IPCC) reported that scientists were more than 90% certain that most of global warming was being caused by increasing concentrations of greenhouse gases produced by human activities. In 2010 that finding was recognized by the national science academies of all major industrialized nations. Affirming these findings in 2013, the IPCC stated that the largest driver of global warming is carbon dioxide (CO2) emissions from fossil fuel combustion, cement production, and land use changes such as deforestation. Its 2013 report states
Human influence has been detected in warming of the atmosphere and the ocean, in changes in the global water cycle, in reductions in snow and ice, in global mean sea level rise, and in changes in some climate extremes. This evidence for human influence has grown since AR4. It is extremely likely (95-100%) that human influence has been the dominant cause of the observed warming since the mid-20th century. - IPCC AR5 WG1 Summary for Policymakers
http://en.wikipedia.org/wiki/Global_warming#Discourse_about_global_warming
Most scientists agree that humans are contributing to observed climate change. A meta study of academic papers concerning global warming, published between 1991 and 2011 and accessible from Web of Knowledge, found that among those whose abstracts expressed a position on the cause of global warming, 97.2% supported the consensus view that it is man made. In an October 2011 paper published in the International Journal of Public Opinion Research, researchers from George Mason University analyzed the results of a survey of 489 American scientists working in academia, government, and industry. Of those surveyed, 97% agreed that that global temperatures have risen over the past century and 84% agreed that "human-induced greenhouse warming" is now occurring, only 5% disagreeing that human activity is a significant cause of global warming. National science academies have called on world leaders for policies to cut global emissions.
In the scientific literature, there is a strong consensus that global surface temperatures have increased in recent decades and that the trend is caused mainly by human-induced emissions of greenhouse gases. No scientific body of national or international standing disagrees with this view.
Line plot of global mean land-ocean temperature index, 1880 to present (2013), with the base period 1951-1980. The black line is the annual mean and the red line is the five-year running mean. The green bars show uncertainty estimates. [This is an update of Fig. 1A in Hansen et al. (2006).] The graph shows an overall long-term warming trend. In the 1890s, the global temperature anomaly was on average slightly below -0.3 °C, with an error range of roughly -0.2 and -0.4 °C. In the 1940s, the global temperature anomaly was on average slightly below +0.1 °C, with an error range of roughly 0.0 and +0.15 °C. In the 2000s, the global temperature anomaly was on average slightly below +0.6 °C, with an error range of roughly +0.6 and +0.5 °C.