Scientists understood physics of climate change in the 1800s – thanks to a woman named Eunice Foote

 In 1824 Joseph Fourier hypothesized that gases in the atmosphere create barriers that trap heat. In 1837 he surmised that over a long period of time, the amount of heat held by the atmosphere could change and be altered by both the Earth’s natural evolution and human activity.  

 John Tyndall (2nd August 1820 – 4th December 1893)  discovered that water vapour and CO2 absorb much more radiant heat than the gases of the atmosphere and argued the consequent importance of those gases in moderating Earth's climate—that is, in the natural #GreenhouseEffect. 

1896 Swedish Nobel Prize winning chemist and scientist Svante Arrhenius concluded humanity could cause global #ClimateChange. He published calculations in The London, Edinburgh, Dublin Philosophical Magazine and Journal of Science showing CO2 in the atmosphere warmed the planet.

 British engineer Guy Callendar, discovered the connection between human activities and #GlobalWarming in 1938. Through detailed journals on weather data, Callendar curated global temperature averages and calculated how much carbon dioxide humans were putting into the atmosphere. 

Canadian physicist Gilbert Pass; 1956 concluded "If at  this centuries end measurements show that atmospheric CO2 rises appreciably and at the same time the temperature continues to rise worldwide, it will firmly establish that CO2 is an important factor in AGW climatic change"