I've been noticing gas-fueled flame pit displays outside some "hip" restaurants, such as this one shown in a Portland Monthly article. I find myself reacting to them with disgust; it looks like they're blowing fossil carbon into the sky like there's literally no tomorrow. The one in the linked article at least has people sitting around it; sometimes they're just alone out front, advertising the owner's environmental folly.
However, I don't know how much CO2 such a display actually emits. Our environmental instincts aren't very accurate, and I fear that I may be getting huffy about these minor displays while blindly causing far more emissions elsewhere in my life.
So, my question is this: how much CO2 does such a display emit relative to an average person's total environmental load? Is it equivalent to one percent of an average person's total emissions? All of a single person's? One hundred people's? Or you could compare it to other typical fuel-related activities: is it a Prius doing 35 mph? A Hummer doing 75 mph? Twenty loaded tractor-trailers on the highway? The Allure of the Seas carrying a full load of vacationers across the Caribbean? (Well, probably not the last one...)
For a baseline, use three of this Uptown Fire Pit Tables. It has a 12" x 42" burner (powered by a 20 pound propane tank in the base), and claims to produce up to 88,000 BTUs, although I'll assume they mean 88,000 BTU/hour. So, the baseline would be a 12" x 10' burner emitting 264,000 BTUs/hour.