NEW YORK - They’re calling it the largest mobilization against climate change in the history of the planet. Hundreds of thousands of demonstrators of all ages and from around the world turned out for the massive People’s Climate March Sunday, filling the streets of midtown Manhattan with demands for global leaders take action to avert catastrophic climate change....

Crowds gathered with banners, flags and floats around Columbus Circle late Sunday morning as music and chants rang out at the start of the march. At exactly 12:58 p.m., demonstrators held a moment of silence in honor of the victims of climate change, followed by a cacophony of noise with drums, cheers and horns to sound the alarm to the crisis.

Organizers estimate that as many as 310,000 demonstrators turned out for the march, though police won’t comment, telling msnbc they don’t release crowd numbers. The crowds were so massive that by mid-afternoon, organizers said they were asking people to disperse and cut the march short by nearly ten street blocks.