New Yorkers, grab your paint brushes and rollers. That’s the message from Mayor Michael Bloomberg, as he and Mr. Global Warming himself, Al Gore, kicked off NYC Cool Roofs, part of the city’s new service program that gets volunteers to paint city roofs white. A cheaper and less intensive alternative to green roofs, white roofs help keep buildings cool by reflecting the suns rays back from whence they came—though they don’t address stormwater issues like their verdant cousins.

“It’s such a simple concept—anyone who has ever gotten dressed in the summer knows it—light-colored surfaces absorb less heat than darker surfaces do,” Bloomberg said from a factory rooftop in Long Island City earlier today. “Coating rooftops with reflective, white paint can reduce roof temperatures by as much as 60 degrees and indoor temperatures by 10 to 20 degrees.” Gore thanked the mayor for keeping the city “at the forefront of enacting innovative policies that reduce our carbon footprint.”

While the Times calls white roofs a stop-gap measure, and more green roofs would obviously be the ideal, they’re gaining in popularity, particularly with the Obama administration. The city’s program is currently in the pilot stages, with plans to cover 100,000 square feet of LIC rooftops over the next two weeks. The area was chosen for its expansive industrial buildings that make it one of the hotter spots in the city—as well as easier to paint.

While the Building Code now requires many new buildings to have white roofs, the city’s sustainability czar, Rohit Aggarwala, noted that 85 percent of buildings that will exist by 2030 are already built. “As a result, we must include existing buildings in our efforts to cool the City,” he said. “The NYC Cool Roofs program, combined with the building code requirement that re-roofing projects include reflective coating, is critical to meeting the City’s goal of reducing citywide greenhouse gas emissions by 30 percent by 2030.”