Freeman Dyson speaks about anthropogenic CO2 and its negligible effect on the Earth's climate.
Humans are affecting the climate, the questions are how much and is it a bad thing.
Increased atmospheric CO2 is leading to a greening of the Earth, with an increase in agricultural yields and wild plant growth, as revealed by satellite data.
It is interesting to note that the same phenomenon was seen in the Carboniferous period 300 million years ago, where atmospheric CO2 was twice what it is today (800 PPM) while mean global temperatures were the same as today. The Carboniferous is named for the proliferation of plant life around the planet that led to the formation of coal deposits. Increased atmospheric CO2 leads to increased plant growth, which sets up a negative feedback loop whereby the warming effects of atmospheric CO2 are negated.
The aptly named Cryogenian period, the coldest time in Earth's prehistory, also saw the highest concentration of atmospheric CO2, several hundred times what it is today.
The whole CO2/warming correlation is a dead horse, and while there's no point killing it anymore, it is entertaining, so let's listen to the brilliant physicist, co-inventor of Orch-OR, and the visionary behind the Orion nuclear powered rocket. Runs 22 minutes.