"It's not hard to imagine the damage weird weather inflicts on our planet. Hurricane Katrina, for example, obliterated coastal communities, wiped out businesses and left hundreds of dead bodies in its wake. Quantifying the cost of such a one-off (we hope) event is pretty easy too: Katrina left us with a bill of $81 billion, according to the National Hurricane Center. But what about the year-in, year-out price tag of our increasingly volatile weather? It's a whole lot harder to calculate the cost of a chronic condition like that — or at least it was. Now a study by the National Center for Atmospheric Research estimates that the bottom-line cost of all the meteorological craziness is a staggering $485 billion per year in the U.S. alone, as much as 3.4% of the country's GDP."