By Tom Feilden
Science Correspondent, Radio 4's Today Programme
Lesley Butler persuaded Irish firms to switch to low energy light bulbs
Ben and Jerry's likes to portray itself as an ethical brand.
One of the company's recent initiatives has been to sponsor a Climate Change College - a project which is sending six young European environmentalists to study and explore the high Arctic.
While they're there, working alongside the scientists monitoring global warming, the students - or "ambassadors" as they are known - will be expected to soak up as much information and practical experience on the impact of climate change as they can.
Then, once they're back home, they will be expected to spend at least a year passing on what they have learnt to other people.
Spreading the word
In short, spreading the word about climate change.
The second expedition into the Arctic wilderness set off in April 2007.
Ambassadors won their places at the Climate Change College with their boundless enthusiasm, but also by coming up with energy-saving campaigns of their own.
Lesley Butler, from County Westmeath in Ireland, got around 30 small businesses in Dublin to reduce their environmental impact by composting their waste and switching to low energy light bulbs.
Neil Jennings, from Kingston-upon-Thames, devised a "Student Switch Off" campaign which encouraged university students to turn off lights and unplug their phone chargers in halls of residence.
He even went so far as to swoop in on freshers week dressed as superhero Power Ranger complete with leotard.
"We believe that climate change is the biggest problem that we face today and we all want to do something about it," he says.
But not everyone is impressed by the Climate Change College.
While environmentalist George Monbiot believes in ethical businesses and is in favour of raising awareness about global warming, he is worried that schemes like this fail to grasp the scale of the problem.
"There is an inherent contradiction and that is between solving climate change or any other environmental problem and continuing to support economic growth," he says.
Jerry Greenfield does not deny that the bottom line is important.
"Well you certainly need to be profitable. But I think the question is, does the profit come first, or does the profit follow operating in a certain way? If you want to have a business that is based on values, you can do that and still make money".
The Climate Change College is a start, but what if initiatives like this end up obscuring a "business as usual" attitude in corporate boardrooms?
When the company was bought by Unilever in 2000 critics said Mr Greenfield and fellow co-founder Ben Cohen had 'sold out'.
Jerry Greenfield is still involved with the company as president of the Ben & Jerry's Foundation, which supports social and environmental projects like the Climate Change College.
He admits the sale of the company was not what he, or Ben Cohen, had wanted at the time, but says some of the original Ben and Jerry's philosophy now informs Unilever's corporate identity.
'Every little helps'
It is an argument that is backed up by John Elkington, from the London-based environmental consultancy Sustainability.
He says that, over time, there is a cross-pollination of ideas.
While Jerry Greenfield accepts the Climate Change College is a drop in the ocean, he still believes change is possible if everybody does their bit.
"I hope that people will have a sense that we have a choice over the kind of world we have," he says. "That it's not pre-determined and we can create our own destiny."
The two young people who visited the Arctic, Lesley and Neil, are in no doubt that they have benefited by one company's bid to highlight environmental damage.
"It's quite astonishing to think that us living our lives are destroying this amazing habitat in our northern hemisphere," says Lesley Butler, who has continued meeting new businesses and researching new ways of making them more environmentally friendly.
"EcoBiz went into full swing when I got back," she says. "We launched a website, held a concert in Dublin and organized the Ecobiz Awards."
Neil Jennings has also been busy, setting up The Student Switch Off at seven universities across the UK since September.
"The overall sense that I've been left with is one of the urgency of taking action on climate change for future generations," he says.
Neil has recruited Eco-Power Rangers - students who pledge to use their energy carefully - and says there has already been a 12% reduction in electricity usage at Kings, 7% at Bradford and UEA and 5% at Birmingham City University.
"It just goes to show that small actions can have a massive difference when enough people adopt them," he says.
"The challenge is to build on the initial good results and to maintain interest in the initiative".
The Ice Cream Man Cometh will be broadcast on Tuesday 4 December at 1100 on BBC Radio 4.
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