"It is sobering to consider the magnitude of climate change during the past 20,000 years, since the peak of the last major glaciation. At that time there were 3.3 kilometres of ice on top of what is today the city of Montreal, a city of more than 3 million people. 95% of Canada was covered in a sheet of ice. Even as far south as Chicago there was nearly a kilometre of ice. If the Milankovitch cycle continues to prevail, and there is little reason aside from our CO2 emissions to think otherwise, this will happen gradually again during the next 80,000 years. Will our CO2 emissions stave off another glaciation as James Lovelock has suggested? There doesn’t seem to be much hope of that so far, as despite 1/3 of all our CO2 emissions being released during the past 18 years the UK Met Office contends there has been no statistically significant warming during this century."
To view the lecture go to this link.