Denialists love to denigrate computer models of earth’s climate. In my opinion they only do this because they’re in denial of the result, not because of any valid evidence. They also love to make the false claim that without computer models there’s no reason to believe that global warming is real, and is going to get worse.
Many of you have seen the graphs (included in the IPCC reports) showing that using computer models, we can reproduce temperature history if we include human factors, but not if we omit them. That’s such powerful evidence that we’re the cause of global warming, it’s no wonder denialists have tried so hard to slander computer models and to insist that without them there’s no solid evidence of man-made global warming. The truth is that you don’t need computer models to show this. Even with very simple mathematical models (and these models are indeed simple) the result is the same. Without human causation, there’s no explanation for the global warming we’ve already observed. With human causation, there’s no explanation for a lack of global warming.PLEASE if you follow one link of mine this year follow this one. It's an easy read for the scientist, and accessible to almost everyone who can read a graph. Pass it around to people who need to see it.
Update: Or maybe not. See comments. What seems clear to those of us in the field may be obscure to others.