Is there any credible evidence to suggest that global warming is a result of human activity?
In summary, the evidence for human involvement in global warming is as follows: 1. in the 19th Century, John Tyndall and Svante Arrhenius established and quantified the basic physics of how CO2 can absorb radiation and re-emit it at longer wavelengths, giving a heating effect in the atmosphere. CO2’s ability to act as a greenhouse gas is easily established using elementary radiative physics and quantum mechanics. It can also be easily demonstrated by laboratory experiment. 2. Measurements of atmospheric CO2 since the 1950’s have shown a significant increase in atmospheric CO2 due to burning of fossil fuels and deforestation. CO2 from fossil fuels has a distinctive isotopic signature (it is depleted in Carbon-13/14 unlike natural sources of CO2), which allows us to identify it in the atmosphere. 3. Global temperature measurements have shown a rise of around 0.7 degrees over the past few decades, which is in line with the CO2 forcing estimate that Svante Arrhenius came up with from his l
