Christmas is a week away, but temperatures more typical of spring than mid-winter are draining global energy markets of any festive spirit. Natural gas prices are depressed across the U.S. and Europe as the world rounds out the warmest year recorded with unusually warm December weather. Demand in the U.K. for gas this month reached its lowest seasonal level in at least 13 years as households turned their heating off. U.S. gas is heading toward its lowest price in two decades amid record stockpiles, and Asian buyers are turning away gas cargoes in the face of an oversupply. “The gas demand just isn’t there and the prices have plummeted,” said Zach Allen, president of Pan Eurasian Enterprises, an adviser to the gas industry. “There’s plenty of gas around and there’s no pressure on supply.” The bad news comes at the end of an already very bad year for prices. […]