Las Vegas will join the worldwide Earth Hour event as lights are turned off around the city – and the Strip – from 8:30 to 9:30 p.m. on Saturday, March 27. The World Wildlife Fund, which organizes the event, held a news conference Tuesday at the “Welcome to Fabulous Las Vegas” sign, which also will be turned off for the event. The organization hopes to send a message about climate change and the importance of energy conservation by getting as many people as possible to turn off their lights.