Cities are going dark for Earth Hour

Cities around the world are going dark on Saturday night for the annual Earth Hour event, which aims to raise awareness about actions people can take for the environment's sake.

The campaign, now in its fourth year, boasting participation of more than 4,000 cities in 131 countries and territories around the world. Hundreds of millions of people are expected to turn off their lights and other non-essential appliances for an hour beginning at 8:30 p.m. local time.

The symbolic act is expected to darken major landmarks around the world, including the Sydney Opera House in Australia, the Eiffel Tower in Paris and casinos on the Las Vegas Strip.

Beyond 60 minutes

This year organizers are putting an emphasis on actions that go beyond just 60 minutes of sitting around the dark and thinking good thoughts about the planet.

"Earth Hour is a chance for people and communities across the globe to join together with the common purpose of a sustainable future for our planet,” Andy Ridley, co-founder and executive director of Earth Hour, said in a news release. "This year Earth Hour asks people to commit to an action, big or small, for the coming year, taking Earth Hour beyond the hour."

The organizers have set up a special website, Beyond the Hour, for examples of what actions to take and where you can make a pledge of your own. Some ideas:

• Cut down on the use of plastics
• Convert your lawn to a vegetable garden
• Conserve water
• Ride a bike, take the bus, or walk instead of driving

What about human achievement?

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If all this sounds like a sacrifice of hard-won creature comforts, you can join up with the Competitive Enterprise Institute's competing campaign, the Human Achievement Hour, which encourages people to leave their lights on "in appreciation for the inventions and innovations that make today the best time to be alive."

For Subscribers

FOR SUBSCRIBERSAbdul El-Sayed tries to woo MAHA voters as Democrats seek inroads with RFK’s supporters

FOR SUBSCRIBERSKratom-like substances are popping up in a typically benign supplement

FOR SUBSCRIBERSGOP super PAC increases its spending for Sen. Jon Husted in tough Ohio race

FOR SUBSCRIBERSRecords reveal tumultuous marriage between slain New York Times executive and wife

FOR SUBSCRIBERSFrom clean energy warrior to ‘wall of shame,’ James Talarico reverses on a fossil fuel money pledge

FOR SUBSCRIBERSCongressional staff planned official trip with luxury stops in Italy and France weeks before election

FOR SUBSCRIBERSA harrowing ordeal aboard an Israel-bound plane

FOR SUBSCRIBERSOpenAI CEO Sam Altman to skip congressional hearing on rogue AI agents

FOR SUBSCRIBERSKey DOJ lawyers departed Trump ‘grand conspiracy’ probe amid pressure to produce, source says

FOR SUBSCRIBERSTrump’s new AI chatbot often links to a site launched under Clinton 26 years ago

FOR SUBSCRIBERSAt MAHA summit, industry CEOs the movement once vilified take the stage

FOR SUBSCRIBERSThis Paralympian has two goals: Win medals and give away $500,000 to her teammates

FOR SUBSCRIBERSCornell rape allegation spotlights stringent New York state laws that have long drawn criticism

FOR SUBSCRIBERSThe debate over AI’s future rages on both coasts

FOR SUBSCRIBERSDecades-old march dispute reignites in Northern Ireland, threatening political crisis

To participate, the free-market advocacy group suggests you "gather with friends in the warmth of a heated home, watch television, take a hot shower, drink a beer, call loved on the phone, or listen to music."

Over on GreenBiz.com, this anti-Earth Hour campaign is summed up as the "fight against the fight against climate change" and offers Web links that should let you can watch the rhetorical battle from a ringside seat.

Meanwhile, the Earth Hour organizers have succeeded in getting statements from world leaders on their participation in the event, ranging from U.N. General Secretary Ban Ki-moon to Colombian President Juan Manual Santos to British Prime Minister David Cameron, who said:

"Sharing responsibility holds the key to fighting climate change. It will be the choices we make as individuals which will mean the difference between success and failure. That's what Earth Hour is all about — millions of people coming together to switch off their lights, tackle climate change and protect our natural world."

Will you be one of the millions of people participating this year in Earth Hour? Weigh in with a comment below.

More stories on Earth Hour:

• Must-see slideshow: Earth Hour around the world
• Earth Hour to hit major tourist draws near you
• Million unplug for Earth Hour
• Earth Hour around the world
• Lights out for climate change
• Sydney to San Fran: Lights dim in Earth Hour

John Roach is a contributing writer for msnbc.com. Connect with the Cosmic Log community by hitting the "like" button on the Cosmic Log Facebook page or following msnbc.com's science editor, Alan Boyle, on Twitter (@b0yle).