Former US president Bill Clinton told more than 100 mayors that stopping global warming depends on them demonstrating that it makes economic sense. He said his foundation was teaming up with Wal-Mart Stores Inc to save cities money on environmentally friendly supplies by buying in bulk.
"We will not get a global agreement on climate change unless you can prove this is not a burden," he said on Thursday.
"This is the greatest opportunity we have had in our lifetimes," Clinton said.
In addressing a climate summit organized by the US Conference of Mayors, Clinton announced that the 1,100 cities represented by that organization would become part of the purchasing group.
Wal-Mart, the US' largest retailer, said it would work with Clinton's foundation and the cities to bundle orders and product specifications for green technology.
Clinton and many of the mayors present criticized the White House, saying it has done little about global warming, and has missed a chance to boost the nascent "green collar" economy -- the jobs created by making the US more sustainable -- from the people who install solar panels to scientists who develop new technologies.
Wal-Mart, which has embarked on a broad environmental drive to cut costs and burnish its reputation, is offering to help the mayors as it has met resistance in some big cities, including New York and Chicago, to its plans to expand into metro areas from its rural and suburban base.
Wal-Mart has set targets for reducing energy use and packaging waste and selling more environmentally friendly products. Steps include switching to only concentrated liquid laundry detergent that reduces packaging and water use, converting its truck fleet to use less fuel and asking suppliers to provide data on their greenhouse gas emissions.
But the company is not the only one whose reputation is at stake. Clinton asked the mayors to think about their legacy, and to keep score from an environmental standpoint.
Cities cover just 2 percent of the planet's land, but are responsible for three-quarters of its greenhouse gas emissions -- and therefore present the greatest opportunity for reducing those emissions, Clinton said.
Much of that progress can be made by picking the low-hanging fruit: replacing wasteful light bulbs with high-efficiency ones, finding the leaks in the water-supply system, capturing the harmful methane produced by landfills and turning it into electricity.