My bad, I misread the bit about 1965, I get it now.

Stevor,

I didn’t mention Svante Arrhenius for two reasons. Firstly I can never remember his name (let alone spell it) and secondly the NAS study was the first to observe a clear and credible warming signal in the temperature record, as opposed to the theoretical (but remarkably accurate) calculations of Arrhenius.

Fourier of course was an exceptional polymath who predicted the GHG properties of CO2 while basically inventing spectral analysis.

Ask most deniers what E=MC^2 is and they can give you a reasonable answer, ask them what RF = 5.35*ln(C2/C1) is and they don’t have a clue.

… in 1896 he [Arrhenius] was the first scientist to speculate that changes in the levels of carbon dioxide in the atmosphere could substantially alter the surface temperature through the greenhouse effect.[4] He was influenced by the work of others, including Joseph Fourier. Arrhenius used the infrared observations of the moon by Frank Washington Very and Samuel Pierpont Langley at the Allegheny Observatory in Pittsburgh to calculate the absorption of infrared radiation by atmospheric CO2 and water vapour. … Arrhenius estimated that halving of CO2 would decrease temperatures by 4â??5 °C (Celsius) and a doubling of CO2 would cause a temperature rise of 5â??6 °C.[5] In his 1906 publication, Arrhenius adjusted the value downwards to 1.6 °C (including water vapour feedback: 2.1 °C). Recent (2007) estimates from IPCC say this value (the Climate sensitivity) is likely to be between 2 and 4.5 °C. Arrhenius expected CO2 levels to rise at a rate given by emissions in his time. Since then, industrial carbon dioxide levels have risen at a much faster rate: Arrhenius expected CO2 doubling to take about 3000 years; it is now estimated in most scenarios to take about a century.

Source :
http://en.wikipedia.org/wiki/Svante_Arrhenius#Greenhouse_effect

So we’ve known about Global Overheating and the role carbon dioxide plays in causing it for over a hundred years now (115 to be precise) although with ever increasing sophistication and more refined understanding.

Minor nit & already noted but I just thought I’d add this extra info. in case folks were interested.

That’s a great clip!