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Humans affect climate.


These key ideas relate to the causes and effects of human-induced climate change. The potential for human activities to increase the temperature of the Earth through greenhouse gas emissions has been described and calculated for over a century. Volumes of scientific research across multiple scientific disciplines now support this principle, and the 2007 IPCC Forth Assessment Report states, "There is very high confidence that the net effect of human activities since 1750 has been one of warming."

The issue of attribution - showing definitely that human activities are causing global climate change to occur - is one of the most active areas of climate research. There is substantial evidence that human activities, especially burning fossil fuels, are leading to increased levels of carbon dioxide and other greenhouse gases in the atmosphere, which in turn amplify the natural greenhouse effect, causing the temperature of the Earth's atmosphere, ocean and land surface to increase. That greenhouse gases do "trap" infrared heat is well established through laboratory experiments going back to the mid 1850s when Sir John Tyndall first measured the effect.

The well-documented trend of increasing of CO2 in the atmosphere is related to exponential increases in human population, massive land cover changes and the burning of fossil fuels. The "smoking gun" that shows clearly that human activities are responsible for recent increases in carbon dioxide in the atmosphere is provided by carbon isotopes (carbon atoms of different atomic weight). These isotopes allow scientists to "fingerprint" the source of the carbon dioxide molecules, which reveal that the increased CO2 in the atmosphere reflects the addition of CO2 from fossil fuel burning.

Source: Climate Literacy & Energy Awareness Network

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© 2018 SKC | Contact Us