On the spectrum of "saving the planet will depend on shifting individual lifestyle choices," to "saving the planet will depend on stronger government regulation," city mayors fall somewhere in the middle. They're policy makers to be sure, but their influence over their constituents' green practices is far more direct than, say, the head of the EPA.

The mayors below (listed in alphabetical order) represent leaders who have significantly shifted the sustainability landscape in their cities — moving beyond splashy, PR spectacles to make real, measurable changes that are good for the planet and empower citizens to make a difference in their daily lives. While these seven individuals are among the "greenest" mayors in the country, this list is not exhaustive. Feel free to leave a shout-out to your own favorite green mayor in the comments.

Mayor Michael Bloomberg

New York City

While Michael Bloomberg stirred up some controversy around his bid to serve an unprecedented third term as mayor of the Big Apple, his demonstrated commitment to green issues was not a cause of the beef. Just two years after launching his comprehensive PlaNYC (PDF) sustainability initiative, the city has "greened" more than 15 percent of its taxi fleet (by going hybrid), planted almost 175,000 trees across the five boroughs, created 141 miles of new bike lanes, and passed a tax measure (PDF) designed to promote green roof construction. Just imagine what Bloomberg could accomplish with another four years.

Mayor Richard M. Daley

Chicago

Chicago may be known for its legacy of boss politics, but with Richard Daley at the helm the city's reputation might shift to "moss" politics. The longtime mayor has helped plant more than 3 million square feet of green roofs across the city (including at City Hall), and is making a bid to host a green Olympics in 2016. Daley is also an avid biker who launched an ambitious plan (10 more miles of bikeways, anyone?) to promote bike riding by 2015. Now if only he could make good on his promise to source 20 percent of the windy city's energy from wind power.

 

Mayor Shirley Franklin

Atlanta

On March 28, 2009, Mayor Shirley Franklin joined citizens, businesses and more than 500 landmark buildings in the city of Atlanta in turning out her lights for Earth Hour — a campaign designed to raise awareness about energy conservation and climate change. Franklin also supports the BeltLine, a comprehensive alternative transportation initiative that will add 22 miles of light-rail transit and more than 1,200 acres of new green space in Atlanta, while preserving "homes, neighborhoods, and historic structures" around the city.

Mayor John Hickenlooper

Denver

Mayor John Hickenlooper's Greenprint Denver plan, launched in 2006, was designed to position Denver as one of the most sustainable cities in the country. Three years later, it's on the right track. During that time, 70,000 trees have been planted in the Mile High City. Meanwhile, low-flow toilets were installed in City Hall, and the city's entire fleet was traded in for biodiesel vehicles.

Mayor Gavin Newsom

San Francisco

Gavin Newsom (aka Mayor McDreamy) is the right person to head up sustainability-loving city of San Francisco. Under his watch, San Fran has launched two successful initiatives previously considered unrealistic for a large metropolis. In 2007, he signed a law banning the use of plastic bags, and in 2008, he created a city ordinance that makes both recycling and composting mandatory. Soon enough, Newsome hopes to head up the green initiatives for the entire state of California — as its governor.

 

Mayor Greg Nickels

Seattle

Remember Greg Nickels? He's the mayor who, in 2005, fought back against the federal government's refusal to participate in the Kyoto Protocol, pledging to meet or beat the climate pollution reduction target suggested for the United States by 2012. Then he challenged other cities' mayors to join him and sign a Climate Protection Agreement. Now in 2009, more than 900 cities have taken the challenge.

 

Mayor Bill White

Houston

Mayor Bill White's commitment to improving Houston's sustainability record is both genuine (if somewhat under-the-radar) and remarkably effective. Under White's leadership, Houston's curbside recycling has expanded, and so has its available greenspace — like the 12-acre Discovery Green park. Meanwhile, 30 miles of track are being added to Houston's light rail — that's the kind of sprawl that Texas can really use.

All photos: Getty Images; Bill White photo: ZUMA Press

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