Cities Dim Lights for Earth

Cities around the world dimmed their lights for an hour tonight to draw attention to global warming, the AP reports. Sydney, Australia, the city where Earth Hour began a year ago, helped get things started, followed by municipalities around the world at 8 pm. in their time zones. Chicago and San Francisco were among the bigger cities in the US that participated. Even Wrigley Field's marquee went dark.

"What's amazing is that it's transcending political boundaries and happening in places like China, Vietnam, Papua New Guinea," said the director of the Earth Hour group in Australia. "It really seems to have resonated with anybody and everybody." The Google home page also got in on the act—it turned its color to black for the day. (More Earth Hour stories.)