City leaders from around the globe gathered Tuesday for an environmental summit hosted by former President Clinton and New York Mayor Michael Bloomberg with a message that the campaign to reverse global warming begins with the world's mayors.
"It is in cities that the battle to tackle climate change will be won or lost," London Mayor Ken Livingstone said.
Mayors and local leaders from more than 30 cities kicked off the conference, known as the C40 Large Cities Climate Summit, which first met in 2005 in London.
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Organizers say cities bear a significant responsibility to address climate change because they cover less than 1 percent of the Earth's surface but generate 80 percent of heat-trapping greenhouse gases.
"Our theme is not whether we should work together, because we know that we must, it is how and how fast we can do so," New York's Deputy Mayor Dan Doctoroff said.
The summit includes mayors from Seoul to Sao Paulo, Albuquerque to Addis Ababa.
The meeting comes at a time when many countries are struggling to address global and national standards for carbon reduction.
This week, U.N. delegates are meeting in Germany to gear up for December negotiations on a new set of international rules for controlling greenhouse gas emissions. The new accord would succeed the Kyoto Protocol, which ends in 2012.
When the Group of Eight major industrialized countries — the U.S., Britain, France, Germany, Japan, Italy, Canada and Russia — met in Germany in June, climate change will also be on the agenda.
Meanwhile, the mayors said Tuesday, local governments can't wait around.
"Where national governments can't or won't lead, cities will," Toronto Mayor David Miller said.
In a discussion on transportation, the mayor of the Brazilian city of Curitiba described his city's solutions, which include a Bus Rapid Transit system, while Livingstone described London's program to reduce traffic by charging motorists extra money in the city center.
Bloomberg recently announced his intention to begin a similar traffic charging program in Manhattan.
London traffic congestion dropped by 20 percent, and carbon emissions in the central zone similarly decreased, Livingstone said. The fee — equal to about $16 — has gone up since it started in 2003.
"People may not like paying the 5 pounds a day, but they certainly didn't want to live with that style of congestion," Livingstone said.
He said his city's next goal is to charge more for higher-polluting cars, a pricing scale that could mean a $50 equivalent charge for the worst offenders.
Organizers of the conference, which ends Thursday, also invited a number of business leaders to this year's gathering in an effort to involve the private sector.
They hope to convince companies that going green — through innovative construction, transportation alternatives and other environmental changes — is a profitable economic move.