A good analogy on how you want to think of Global Warming is like looking at a graph of the stock market. You can pick periods where the market was down, when it went sideways and when it went up. However, looking at the graph as a whole the overall trend is up. There's no denying that. That's rooted in fact.
Same with Global Warming. You can look at periods when temps are up, down and sideways, but the overall trend is warming. The facts are polar ice caps are melting, oceans are rising and temps are rising. So Global Warming is happening, there's no disputing that.
And there's no disputing mans contribution. Except with science deniers, but some of these people are the same people who think Adam and Eve were riding around on dinosaurs 6000 years ago.
We can't let ignorance rule the day when it comes to the only planet we have.