March 29 (Bloomberg) -- Five hundred businesses in Chicago will turn off nonessential lights from 8 p.m. to 9 p.m. tonight to raise awareness of climate change in the city's first so- called Earth Hour, the Chicago Sun-Times said.

Businesses and residents of participating cities will turn off lights for 60 minutes starting at 8 p.m. local time for Earth Hour, which began last year in Sydney, Australia, the newspaper said. In Chicago, the Wrigley Field marquee sign, Michigan Avenue storefronts and the Sears Tower antennae will darken; traffic and street lights will not be affected, the Sun-Times said.

Atlanta, Phoenix and San Francisco are also participating, the newspaper said. No power surge is expected when the lights are turned back on, Chicago Chief Environmental Officer Sadhu Johnston told the Sun-Times.

To contact the reporters on this story: Linda Shen in New York at lshen21@bloomberg.net.

Last Updated: March 29, 2008 14:57 EDT