Happy birthday anthropogenic climate change hypothesis75 years ago this April, Guy Stewart Callendar, a steam engineer, inventor, and talented amateur meteorologist, made scientific history when he published an important scientific paper in the in the Quarterly Journal of the Royal Meteorological Society linking the burning of fossil fuels to the warming of the Earth's climate.
Here's Callendar's hand-drawn graph showing his data on the "CO2 effect":
Callendar's work built on the work of others, and others took his hypothesis and refined them, but it was still a very important milestone in our understanding of the dangers of running a gigantic chemical experiment with our planet's atmosphere by pumping billions of tons of carbon into it. Of course at the time, Callendar couldn't foresee just how much fossil fuels we would be burning over the next 75 years and what kind of negative effects this could have (these realisations would come later), so he believed that the anthropogenic warming from the greenhouse effect would be beneficial, concluding in his paper:
It may be said that the combustion of fossil fuel, whether it be peat from the surface or oil from 10,000 feet below, is likely to prove beneficial to mankind in several ways, besides the provision of heat and power. For instance, the above mentioned small increases of mean temperature would be important at the northern margin of cultivation, and the growth of favourably situated plants is directly proportional to the carbon dioxide pressure. In any case, the return of the deadly glaciers should be delayed indefinitely.