All those charts that show how the Earth's temperature varies with CO2 concentration over the last 1/2-million years provide no cause for the rise in CO2 prior to the rise of humans. Even if CO2 caused an increase in temperature, what caused the rise in CO2 ??? Just because I live in a northern country, I have a profound innate understanding of how seasonal temperature is affected by how much sunlight we get. I mean, seriously there is a direct correlation between how many daylight hours we have and the average daily temperature. I varies sinusoidally on an annual basis. Variation in solar irradiance provides the best fit to global temperature variation. I don't know why providing a link makes my opinion more believable, but it does, so here's one:

source: Junkscience

Now you'll notice that there is a shorter periodicity, on a 10-year scale roughly that might indicate sunspot activity. But that can't be used to imply longer-term variations in temperature, and especially to imply that the influx of cosmic rays is affected and in turn affects climate. The global variation in temperature is simply forced by the amount of solar radiation we receive. It's so simple.

Now, that's not to say that burning fossil fuels isn't going to become a problem. Our dependence on them is the problem. Free market economics does not provide for planning on a 10-50 year timescale. That's also a problem. Some people don't think that's a problem, but I do.