[quote=zk]
The one that shows CO2 levels fluctuating between 180 and 300 ppm for the past 400,000 years before spiking to 380 over the last 65 years. When I saw it, I wondered how climate change deniers explained it, but I didn’t think I knew any. livinincali, are you saying that “we” aren’t sure that man caused this spike, or that that spike didn’t cause climate change, or that there is no climate change, or something else?[/quote]

There’s certainly more CO2 in the air caused by man but it’s effects on the climate are not completely understood. Yeah sure we know what happens when you pump CO2 into a box and those climate models probably used that as a model, but those models haven’t accurately predicted the warming that would occur. Something more complex is happening that the scientists haven’t figured out yet. CO2 in the atmosphere is a trace gas. 300 parts per million is 0.03%. Maybe changing that to 0.04% isn’t going to have that big of an impact on the climate after all. Of course every time it’s a little hotter than usual or a hurricane hits New York we can blame it on climate change. Then hopefully we can get the people to support a new tax or a new ban on something.

To go back to what it was in the previous millions of years would require us to pretty much completely stop using fossil fuels. So you have a choice, reduce fossil fuel usage significantly and lower the standard of living for all of us. Or replace it with a different technology and understand that you aren’t going to be able to do it with wind and solar. We could probably do it with fast breeder Thorium nuclear reactors. The dream would be solving the mysteries of recovering net positive energy from fusion. Wind and solar might have a place where it makes sense but it’s never going to be more than 10-20% of total power generation without some sort of storage technology break through