"Looking for more sustainable ways to do things is part of our DNA," says Charlie Raynes, senior manager of marketing for the company. "We've been including this kind of questioning in our print advertising RFPs for years, and we've been using recycled materials for our out-of-home advertising for some time."

So when it came time to create the $1.5 million campaign for Earthkeepers, one of its most environmentally friendly offerings yet, "we really wanted to challenge ourselves, and figure out if we could do this." (Arnold is Timberland's creative agency; Mullen's mediaHUB is the media agency. Both are based in Boston.)

Meanwhile, the ads come at a time when Timberland could use a sales boost. Recently, the company, which has been struggling, announced that it would shutter 40 specialty retail stores and lowered its sales forecasts for both the quarter and the year.

In addition to the TV spots, the company is also buying outdoor ads that feature tires and old soda bottles bent in the same shape as the boot, which has an outsole made of 30% recycled content. When the campaign is over, the vinyl from the outdoor ads will be sent to Maine for repurposing, and then sold as tote bags in Timberland stores. "The idea for the whole effort was to keep everything within a 150-mile range," Raynes says.

While Timberland may be the first to offset its TV spot, it won't be the last, says Don Carli, senior research fellow at the Institute for Sustainable Communications, as well as its Sustainable Advertising Partnership, based in New York. "It doesn't matter whether ads run in print, on TV or digitally," he says. "They all have an environmental and social impact that can be measured and needs to be managed."

And companies of all stripes, even smokestack-free media companies, are suddenly being forced to address questions about carbon. First, suppliers - most notably Wal-Mart, which has been pressuring suppliers to green up their act - are demanding it. And second, Carli says, consumers are increasingly evaluating a brand's environmental impact when they make a purchasing decision. "Mainstream consumers aren't going out of their way to buy products that have environmental benefits, whether it's organic or fair-trade. But all things being equal, that could be the deciding factor," he says. "Increasingly, consumers are using the lack of green positioning as a way to punish brands. And consumers continue to be highly skeptical about the authenticity of green claims."

They're also somewhat bewildered. "Companies have rushed to differentiate themselves, and it's resulted in a kind of green fog, like a big tower of eco-Babel. There's a fair amount of consumer confusion." And of course, it's also worth remembering that plenty of Americans don't have global climate change on their radar at all: A recent Yale University/Gallup poll found that 50% of Americans say they are personally worried about global warming. Of those, 15% say they worry "a great deal."

Companies like Timberland, who can seamlessly blend their mission, message and product, have an advantage in reaching such consumers. Other leaders in the category include luxury jewelry marketer John Hardy, who has completely offset the carbon damage of advertising in high-end glossy magazines, which create methane in landfills, far more serious than carbon dioxide. He's converted the credits into small bamboo clumps on an island near his home in Bali. After giving the seedlings to locals, he promises to buy the bamboo back within five years, providing the farmers harvest it sustainably.

Of course, marketers aren't alone in trying to find ways to analyze the environmental impact of ads. Grey Advertising, for example, has launched an internal Green Team, with 30 members, to encourage new initiatives within the agency. And it created Green-it-Forward.com, "as a way to get other agencies involved in the conversation," says David Prince, a Grey account exec who helped found the group. For now, he says, initiatives have focused on sustainability on the agency side. "Changing light bulbs is great, but we need to find ways to show people there's a lot more to being green, and we wanted to find a way to get colleagues throughout the industry thinking about the environmental consequences of advertising decisions."

For Timberland, the "hope was that the result of our ad campaign was the creation of clean energy," says Raynes. "We think the important thing is that this could start other people having the same kinds of conversations. And we hope it sets the table for the future."

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