Quote: SYDNEY, Australia -- Madonna, Metallica, The Police and Kanye West are among the top names listed to perform at a series of climate change concerts being held around the world starting Saturday in Australia.

The biggest names will appear at Live Earth concerts in London and the United States, with more modest lineups of mostly local and regional acts in Australia, Japan, China, South Africa, Brazil and Germany.

Live Earth was inspired and is backed by former Vice President Al Gore's campaign to force global warming onto the international political agenda by generating a groundswell of public concern.

But critics say that it lacks achievable goals, and that bringing jet-setting rock stars in fuel-guzzling airliners to plug in to amplifier stacks and crank it up loud may send mixed messages about energy conservation.

"The last thing the planet needs is a rock concert," The Who's singer Roger Daltrey recently told a British newspaper.

Organizers say the concerts will be as green as possible, with a tally of energy use being kept. Proceeds from ticket sales will go toward distributing power-efficient light bulbs and other measures that will offset the shows' greenhouse gas emissions, they say.

"This is going to be the greenest event of its kind, ever," Gore told The Associated Press recently. "The carbon offsets and the innovative practices that are being used to make this a green event, I think, will set the standard for years to come."

More than 150 artists will perform at the eight concerts. Other venues are in Tokyo, Shanghai, Johannesburg and Hamburg. The New York venue is actually being held in East Rutherford, N.J.

There have been some organizational hiccups. A judge canceled the Brazil concert because of security concerns before reversing the decision just two days before the event, and lukewarm public interest caused a planned show in Istanbul, Turkey to be called off.

Promoter Michael Chugg said on Friday there were still plenty of tickets available for the Sydney show.

But organizers were predicting live broadcasts on cable television and the Internet could reach up to 2 billion people. Scores of short films and public service announcements will be aired giving the audience tips about how to conserve energy and reduce their environmental impact.

Rob Hirst, drummer for Midnight Oil and performing at Live Earth in his new band the Ghostwriters, said at the launch of the Sydney concert lineup that the traditional rock star lifestyle was not eco-friendly.

"Any of the musicians here who've spent 24-to-30 years roaming the globe on planes, trains and automobiles should have a mighty guilt complex about what they've done to the environment," Hirst was quoted as saying by local media.

"But it's not too late to change."

Laid-back rocker Jack Johnson is the only international act in Sydney, which features the reformed 1980s pop group Crowded House as top billers.

The Tokyo concert, featuring artists including Ai Otsuka, Kumi Koda and Linkin Park, comes next, followed by the other cities. Madonna and the Black Eyed Peas feature in London, while Red Hot Chili Peppers and Alicia Keys are among acts in the United States.