Can Mayors Step Up in the Global Warming Battle?

LIMA, Peru—Ban Ki-moon, the soft-spoken South Korean who is the general secretary of the United Nations, looked out on a sea of international journalists assembled during a press conference last week and unloosed the verbal equivalent of a warning flare.

"Our planet has a fever and it is getting hotter every day," he said during the U.N.'s 20th climate summit held in Peru. "We must take climate action now. And the more we delay, the more we will have to pay. This is our only world. Future generations should be able to live prosperously."

Such dramatic warnings from an international leader sent a shiver through me as I listened at close range. In my week of covering the summit, where delegates from 196 nations gathered to draft an imperfect accord to reduce greenhouse gas emissions and thus try to slow global warming, I felt too often that the task of literally saving the earth was beyond our reach.

Look no further than the new leadership of the U.S. Congress, which, despite all scientific evidence, tends to view climate change only in political terms and seems intent on reversing President Obama's pledge to reduce America's greenhouse gas emissions by burning less coal for power generation and through greater fuel-economy standards for cars and trucks.

But my grim outlook brightened one evening in a conversation with Riley Duren, an engineer with NASA's Jet Propulsion Laboratory at Cal Tech in Pasadena, Calif. He specializes in satellite technology that monitors greenhouse gas emissions around the world.

He explained that government leaders in developed countries like the U.S., the European Union and Australia, and in developing countries like China and India — all of which are leading carbon emitters — will always be conflicted and often thwarted by politics and economics when dealing with climate change.

But mayors of cities? That's another story.

"More than 70 percent of all carbon emissions come from cities," Duren explained. "If you total up the emissions of the world's 50 largest cities, they would collectively become the world's third largest emitter behind China and the U.S. So when you think about it, mayors can have a bigger impact on fighting climate change than heads of state."

It turns out that former New York City Mayor Michael Bloomberg is leading this charge. He serves as a special U.N. envoy on cities and climate change and is backing an effort called the Global Protocol for Community-Scale Greenhouse Gas Emission Inventories, or GPC. The goal is to establish international standards for monitoring and measuring citywide carbon emissions. Once a city knows the sources of its emissions and how much, it can develop strategies to reduce them.

Bloomberg said in Lima that the more cities that take part in the GPC, the greater impact it will have. Duren, my new friend at NASA, agreed.

"If you want to hold out for having an impact on all emissions, you need the entire world, and that's really difficult," Duren said. "But if you want to focus on up to 80 percent of emissions, you're down to about 1,500 cities. Mayors can be much more responsive on issues like this."

Duren confirmed that cities the size of Charlotte, Raleigh, Greensboro and Winston-Salem would be on that list of 1,500 cities. Thus, meaningful action on climate change can take place locally, regardless of what Congress decides to do or not do. Are you listening, Mayors Vaughan and Joines?

Establishing baselines for carbon emissions is critical; so is monitoring year-to-year changes. But strategies that work are already being implemented in cities like Los Angeles, Rio de Janeiro and Paris, not to mention Charlotte and, to a degree, Greensboro.

Strategies include improving mass transportation, shifting to LED street lighting and patching natural gas and methane leaks in infrastructure. Others include enhancing the energy efficiency of public buildings and schools through insulation and expanding solar power generation. Big cities are doing these things, which not only reduce carbon emissions, but also save tax dollars and improve air quality.

Charlotte? It recently launched an ambitious effort to plant 500,000 trees in the next 35 years to increase the city's canopy of shade to 50 percent. That alone will have a cooling effect that will not only reduce runoff and improve water quality, but also reduce energy demand.

Meanwhile, Greensboro's 4-mile greenway around downtown will promote more recreation, yes, but like other cities across the country looking to cut commuter traffic and pollution, it will provide a carbon-free way for many to get to and from work.

Mayors can't solve the problem alone, Duren told me. Still, the thing that excites him about city leaders fighting climate change is that it gives him something hopeful to talk about with his relatives back home. The impact of global warming is so grim and foreboding that most people would rather not think about it.

"Sometimes it feels like everything on the planet has to change to have an impact on climate change," Duren told me. "But the message is — maybe we don't have to solve everything to save the planet. Maybe what we need are finite locations, finite decision-makers, finite change. A lot mayors are already doing this. That's hopeful. That's a light at the end of a tunnel that isn't a train."