NEW YORK — Meaye Ndoye, a 34-year-old student from Brooklyn, volunteers frequently in his community, but he’s never participated in the type of public march that seems to occur on a weekly basis here, calling for an end to America’s military presence in Iraq or protesting the NYPD or celebrating unions.

But that’s going to change Sunday, when he participates in what organizers are hoping will be the largest march ever about climate change.

Organizers of the People’s Climate March are expecting anywhere from 100,000 to 400,000 people from more than 1,000 organizations to turn out Sunday and raise their voices ahead of a U.N. summit on climate change Tuesday. They’re hoping to draw people like Ndoye who haven’t participated actively in the environmental movement in the past, but are deciding that now is the time.

Participating groups include Amnesty International,, the Sierra Club, and dozens of unions, religious organizations and student groups.

“It’s a duty, because I’m human, and this is my home,” Ndoye said, sitting in a crowded room in Midtown Manhattan where he had turned up to volunteer to make calls to remind people about the march, after seeing signs for it on the subway last week.

The march will begin at Central Park West and make its way down to 11th Avenue and West 34th Street. Along the way, organizers have planned a moment of silence at 1 p.m. to honor those affected by climate change. After the moment of silence, they’ll kick off a noise bonanza, with more than 20 marching bands and people carrying instruments to make noise.

The event also has counterparts across the world, in such countries as India, Nigeria and London, where separate marches will also be taking place Saturday and Monday.

“The goal is not just to be the largest climate march in history but also to be the most diverse,” said Caroline Murray, the field director for the event. “Traditionally, you think of climate change as the cause of more traditional environmental groups, but this is a much broader array of activists.”

The march comes as polls show increasing support in the United States for policies to combat climate change.

Two in three registered voters in the U.S. think global warming is happening, and more than half of them are worried about it, according to a poll conducted by the Yale Project on Climate Change and the George Mason University Center for Climate Change Communication. Two-thirds of Americans say they support laws that would support the use of renewable energy to wean the country from fossil fuels, and two-thirds also support setting carbon dioxide emission limits on coal-fired power plants.

Despite that support, people rarely get involved in any sort of political movement around climate change, said Edward Maibach, director of George Mason University’s Center for Climate Change Communication.

The George Mason poll also found that only one in four Americans said they would be willing to join a campaign to persuade elected officials to take action on global warming. And 13 percent said that they would participate in an organization engaging in nonviolent civil disobedience against activities that make global warming worse, if they were asked by a person they liked and respected.

Instead, they will change the behaviors that are easy to change, such as recycling things at home and buying only products that are energy efficient.

“What we have found is that people who are concerned about climate change — many of them are changing their behavior in a capacity as a consumer — but relatively few of the people who are concerned are expressing themselves as citizens,” Maibach said.