Unless you’ve been living under a rock, there’s no need to explain that the poster to the left is the work of street artist Shepard Fairey. The ‘Vote Earth’ concept designed for Earth Hour ’09 is easily linked to the artist’s ‘Hope’ portrait of Barack Obama.

Commissioned by Leo Burnett and WWF, the poster will appear in Canada in a PSA, wild posting and online as part of the first global marketing effort since Earth Hour was born in Australia three years ago, says WWF-Canada president Gerald Butts. ‘This is the one opportunity that citizens all over the world have to come together and say ‘We’re concerned about climate change,” he says, adding that the goal is to get one billion participants this year. ‘Shepard very cleverly picked up on the ‘light switch and vote’ concept and indicated that [this] is your way of voicing your vote on climate change.’

The hope is that Fairey fans will literally steal the poster – although it’s also available for download from Wwf.ca/earthhour – and get the message to turn off their lights for one hour at 8:30 p.m. on March 28. ‘It’s a quintessential viral campaign,’ says Butts, adding that 10 million Canadians spent an hour in the dark last year – more than any other country.

WWF’s Earth Hour partners in Canada include Sears, CBC, Coca-Cola and Maple Leaf Sports and Entertainment.