Climate Central: The normally tame Bow and Elbow Rivers that course their way through downtown Calgary, Alberta, have taken over the city, transforming Canada's fourth-largest city into North America's Venice. A slow-moving storm system, coming on top of an unusually wet spring, has produced massive flooding across southern Alberta, prompting tens of thousands to hastily evacuate sections of Calgary, and producing surreal images of the city's landmarks, such as the Calgary Stampede grounds, under several feet of...