As I write this from a borrowed office near Manhattan’s UN plaza, a police officer leans against the window a few feet away. I can hear the crackle of her radio and the tap of her nightstick against the glass; I can see her stance, weary yet alert. For the last hour, she’s been carefully eyeing each pedestrian who wanders past.

Because of this week’s UN General Assembly, including a high-level climate summit that begins tomorrow, the neighborhood is full of police officers guarding newly erected metal barriers. With more than 100 world leaders in town—including President Obama—security is understandably tight.

I also noticed this extra security at today’s Climate Week NYC opening ceremony, where celebrities and world leaders (including Rt. Hon. Tony Blair, Hugh Jackman, and UN Secretary General Ban Ki-Moon) kicked off a week of climate change events. In just one day, I’d gone from a grassroots stunt led by Oxfam campaigners and featuring thousands of volunteer activists—the Human Countdown in Central Park—to an invite-only panel that showcased the voices of power.

Even so, I was pleasantly surprised by some of the speakers. Jackman in particular talked about his recent trip to Ethiopia and meeting a drought-affected coffee farmer who’s conserving methane from manure to provide electricity for his family. “Poor people have done the least to cause climate change, but they’ve been hit hardest by it,” he said. “They need voices—real voices—in world forums.”

The Secretary-General, who convened this week’s summit, emphasized that “we must seal the deal in Copenhagen … This is a political and moral imperative for all of us, particularly [UN] leaders.”

But as the speeches wore on, they began to sound hollow, well-intentioned but vague. The vaulted ceilings and high marble walls of the New York Public Library felt far away from the communities actually battling climate change—not to mention the everyday activists who bring real passion to the fight.

That is, until Kumi Naidoo took the podium. “Far too many of our leaders seem to be sleepwalking into a crisis that’s affecting far too many people in the developing world,” declared the chair of the TckTckTck campaign. “We cannot accept just any deal in Copenhagen. We need a deal that’s fair, ambitious, and binding … with a sense of climate justice.” Next to me, Sister on the Planet Sharon Hanshaw nodded vigorously in approval.

And on the way out, a man handed us copies of what appeared to be the New York Post, but was really a stunt paper created this morning by the Yes Men. “We’re screwed!” the headline screamed, predicting “massive climate catastrophes, public health disasters” but promising that “New York Fights Back!” I later learned that over 2,000 volunteers had fanned out across the city to distribute copies.

As I tucked the fake paper into my bag, I couldn’t help but smile. The grassroots voice had found a way in after all.