Editor's note: The following story originally appeared in the August 2008 issue of Seattle Metropolitan magazine, and is reprinted with permission.

In February 2005, Seattle Mayor Greg Nickels started an urban green revolution with 24 simple words. Frustrated with the Bush Administration's inaction on global warming, Nickels decided to work the problem himself. "If the federal government is not going to sign on to the Kyoto Protocol," he said in his State of the City speech, "why can't we just do it at the local level?"

Since then, 850 cities have signed onto Nickels's brainchild, the U.S. Mayors Climate Protection Agreement. They've pledged to cut their greenhouse gas emissions to 7 percent below 1990 levels by 2012. The mayor's bold gesture inspired hundreds of other city, state, and regional climate change initiatives.

For Nickels, the move paid off handsomely. Rolling Stone, Vanity Fair, and Time hailed him as America's green mayor. The Sierra Club, the U.S. Environmental Protection Agency, and Harvard's Kennedy School of Government showered him with awards. The word "visionary" became part of the mayor's biographical boilerplate.

Now, three years later, Nickels's national reputation has become so tied to green urbanism, it's easy to forget that it wasn't always so. When he came into office in January 2002, Seattle's priorities weren't climate change and carbon footprints; they were gridlock and crime. The mayoral election of 2001 seemed to pit the two issues against each other. Nickels, a transportation wonk and longtime light-rail champion, was the gridlock grinder. Mark Sidran, a no-nonsense former city attorney, was the crime fighter. In a city forever stuck in traffic, and still reeling from the WTO and Mardi Gras riots, gridlock jitters trumped law and order–barely. Nickels's margin of 3,158 votes made it Seattle's closest mayoral race since 1912.

Margin, schmargin: Nickels took office as if he'd captured every vote except Sidran's mother's. The city's chattering class worried that Nickels, a protégé of former Mayor Norm Rice (aka Mayor Nice) would let the city stagnate in Seattle process, a governing style that seeks consensus, avoids hurt feelings, and results in policies as clear and strong as mush. Not to worry. Candidate Nickels campaigned as a "Seattle-style" politician, but it turned out he'd bought his mayoral style at the shop of Richard J. Daley & Son. Moving quickly to consolidate power, Mayor Nickels fired four department directors, including popular Department of Neighborhoods chief Jim Diers, and replaced them with his own loyalists. In years past, city staffers worked directly with council members to develop legislation. Nickels put an end to that, sending a message that city departments would dance to the mayor's tune. He threatened to cut funding for a Greenlake-based fire engine if the council didn't restore an increase in the mayor's office budget — normal hardball politics elsewhere, but a little nastier than Seattle was used to. By the end of his first year in office Greg Nickels had established one incontrovertible fact. He wasn't just the mayor. He was the boss.

He wasn't a green boss, though. Nickels sailed through his first term without much in the way of an environmental agenda. Sustainable planning and building design were the hobbyhorses of his predecessor, Paul Schell, a developer and former city planning director. Nickels wasn't against green buildings per se, but the new mayor was a bare-knuckled pothole fixer, not a bow-tied architect. His environmental policy was unfocused and unambitious — Nickels himself described it to me recently as "a nice list of random acts of kindness for the environment."

Then came the mayor's climate-change conversion. It happened over the winter of 2004-05. In November the reelection of President Bush confirmed that the federal government would ignore climate change for four more years. Then winter failed. Warm temperatures scuttled the Northwest ski season. Officials at Seattle Public Utilities spelled it out for the mayor: No snowpack meant no water for the city. Cascade mountain snow was Seattle's natural reservoir. Warmer winters meant more of it would fall as rain and not get stored for the summer, when city water use peaked. And this wasn't an anomaly. Snowpack levels had been falling since the 1950s. "That was my 'aha' moment," Nickels said when I sat down with him in his seventh-floor office at City Hall. "The U.S. wasn't participating in the Kyoto Protocol, but we here in Seattle were experiencing the direct effects of global warming."

So on February 16, 2005 — the day the Kyoto agreement went into effect — Nickels announced that Seattle would cut its greenhouse gas emissions in the year 2012 by 7 percent compared to 1990 levels. To reach that goal, the mayor created an ambitious Climate Action Plan for the city, a $37 million to-do list that included everything from denser zoning to bike lanes. The idea caught on. Last November, at the U.S. Conference of Mayors Climate Protection Summit in Seattle, host Greg Nickels triumphantly announced that Seattle had already surpassed its goal. The city was Kyoto-clean five years ahead of schedule. The assembled mayors gave him a rousing ovation. Nickels beamed, triumphant.

There's an open secret about that triumph: Mayor Nickels's Climate Action Plan had nothing to do with meeting the city's Kyoto goals. The results were based on the city's 2005 greenhouse gas emissions, measured before Nickels's plan went into effect. So how did the goal get met?

To find out, I paid a visit to Roel Hammerschlag, a greenhouse gas expert at the Seattle branch of the Stockholm Environment Institute, a sustainable development research group. He sports funky glasses, wears heavy wool sweaters, and works out of a cheap office in the University District. He's the consultant the City of Seattle hired to compile the city's greenhouse gas inventory, no easy task. "Countries generally have good accountings of their fossil fuel use, and states have good data, too," Hammerschlag told me. "But once you go below the state level, everything falls apart. No city tracks the goods that go in and out of its boundaries." City greenhouse gas inventories are so new that standards and practices are still emerging. "It's not entirely clear what you should do," Hammerschlag said. ICLEI, the International Council for Local Environmental Initiatives, is working with other consultants on a standard protocol for cities. It's an inexact science — Hammerschlag is helping invent the process as he goes along.

Still, his report titled "2005 Inventory of Seattle Greenhouse Gas Emissions: Community and Corporate" gives a clear 52-page snapshot of the city's CO2 output. Because hydropower supplies so much of our electricity, the city has a leg up on most other American cities. Our problem can be summed up in three words: cars, cars, cars. Nearly 60 percent of our greenhouse gas emissions come from transportation, the vast bulk of that from road traffic — and that increased 5 percent between 1990 and 2005.

If you read Hammerschlag's report closely, you can see how the Kyoto goals were met. Between 1990 and 2005, the price of natural gas fell relative to home heating oil, causing many home owners to switch to natural gas, which produces less carbon dioxide than oil. That was a 1 percent drop. Old landfills at Interbay, Genesee, Judkins Park, and South Park slowly dissipated their methane, an enormously potent greenhouse gas. That was another 1 percent. The biggest drop — 5 percent — came from Seattle City Light, which made itself carbon neutral by selling off its share of the Centralia coal-burning power plant and buying wind power. City Light had been working since 1999 to get its footprint to zero, and it finally reached that goal in 2005. The man most responsible for zeroing out City Light was Nickels's predecessor, Paul Schell, who started the process more than a year before Nickels took office. So far, so good: we're at a 7 percent decrease already. But that's partly offset by emissions from more cars, more boats, and more construction over the past 15 years.