There are a lot of things that keep AQR founder Clifford S. Asness up at night: The Captain American shield tattooed to his bicep and the nagging, haunting feeling that he should've gone bigger. The level of security in his Greenwich office, and whether or not the prized action figures he keeps behind his desk are safe. Batman, and if he'll ever get to ride next him in the Batcycle's sidecar. Commenters on the internet. Big red dogs. Wine. The durability of his computer monitors. Right there alone represents hours of sheep counting and dozens of glasses of warm milk.

Luckily, there is at least one thing Cliff doesn't have to grapple with before getting some shut eye and that's the effects of global warming on the planet. The hedge fund manager recently put on his lab coat and determined the following:

His conclusion: It’s not as big of a problem as some suggest. Cliff Asness, who runs AQR, one of the largest hedge fund firms in the world, e-mailed out a research paper on Tuesday to reporters and others making his arguments on climate change. The paper is labeled “very preliminary,” and Asness asked that it not be directly quoted. The paper focuses on a chart of the Earth’s surface temperatures going back to 1880. Asness, who wrote the paper along with his co-worker Aaron Brown, does not deny that global temperatures are rising. But he says temperatures are rising at much slower rate than many suggest. What’s more, Asness and Brown say, based on the current pace of global warming, it will take another 500 years before the changes become a real problem.

...while others, who study these sorts of things for a living:

“I’m not sure about the idea of beating people about the head and shoulders, but within less than a year, you will look like complete fools (if you buy this crap),” e-mailed Columbia University environmental science professor James Hansen, who took a look at the Asness and Brown paper at Fortune’s request.

Top hedge fund manager: Global warming isn't a danger [Fortune]