Getting people to care means showing them how global warming will affect their lives. Many speakers pointed to the 1995 heat wave in Chicago that killed hundreds. Such heat waves will become more common, so cities should take notice. Also, considering growth that cities deal with, water sources will be affected by climate change. Some places might see more rainfall, others less.

Heat, water sources and growth are all local issues that will be affected by climate change. The mayors, then, should take notice and plan ahead. In addition, they should take measures to conserve energy, which leads to fewer greenhouse gas emissions, speakers said.

Redford told the mayors they must effect change at the local level because federal leaders haven't initiated much.

"The best and most significant changes come from the grass roots," he said. "They come from the ground up."

Indeed, many mayors at the summit are sharing ideas with others, giving them specific tools they can implement to reduce energy consumption and thus the need to burn carbon-based fuels.

Among those ideas are mandating that buildings be designed and built according to green building principles that call for recycled materials to be used during construction, that brownfield be utilized when possible and that energy-efficient designs and systems be employed throughout the structure, among other criteria.

Other "low-hanging fruit" includes replacing traditional light bulbs with more energy-efficient ones or replacing traffic lights with brighter, less energy-dependent models.

"This is really about tangible steps that can be taken and have been taken all across the country," Redford said.

Former Vice President Al Gore wrapped up the evening with a speech titled "Global Warming: A Planetary Emergency," which was closed to the press.

---

E-mail: bsnyder@desnews.com