
You're right, CO2 levels and Temperature don't correlate at all, and I'm sure that huge spike at the end isn't caused by humans.
I look at it this way - the Earth is getting warmer. That is a fact. Whether it is long term or short term it is definitely getting warmer. Are humans contributing? Well ask yourself, is the Pope Catholic?
We know humans effect weather. Pollution causes acidity in rain. Cities cause warmer heat islands at night. In addition, we've been burning up fossil fuels over the last 100 years that have taken up to 100,000,000 years to form. All of that energy over 100 million years released in 100 years and people think that wouldn't have any effect whatsoever?
Plus, no matter what, what is so wrong with trying to find cheaper more renewable forms of energy? What is so bad about curtailing pollution and making more efficient, greener factories? Nobody wants to live in a dirty, smelly world.
On top of that, you can also think of it this way. Either we take action or we don't. Let's say we take action - worse case scenario is we end up with a greener world and we spent a little money that we didn't need to. If we don't take action, the worse case scenario is that we're up **** creek without a paddle.
I think that even if you have doubt about the data, it's pretty obvious what path we must choose.