At exactly 1pm on Sunday, the streets of New York City are going to fill with the sound of clanging pots, marching bands, church bells and whatever other kinds of noisemakers that participants of the People’s Climate March decide to bring along.

It’s being called the “climate alarm”, and the general idea is that a whole lot of people are going to make the very loud point that climate change is a true emergency for humanity, the kind of threat that should cause us to stop what we are doing and get out of harm’s way.

Is it a stunt? Well, sure, all protests are. But the mere act of expressing our collective sense of climate urgency goes beyond symbolism. What is most terrifying about the threat of climate disruption is not the unending procession of scientific reports about rapidly melting ice sheets, crop failures and rising seas. It’s the combination of trying to absorb that information while watching our so-called leaders behave as if the global emergency is no immediate concern. As if every alarm in our collective house were not going off simultaneously.

Only when we urgently acknowledge that we are facing a genuine crisis will it become possible to enact the kinds of bold policies and mobilize the economic resources we need. Only then will the world have a chance to avert catastrophic warming.

It’s not simply that our leaders aren’t leading us – at an appropriate gallop – away from fossil fuels and towards the renewable energy revolution that is both technologically and economically feasible. It’s that most of them are doubling down on the very energy sources that are most responsible for the crisis, cheering on the extractive industries as they dig up the most greenhouse gas-intensive fossil fuels on the planet: oil from the tar sands, gas from fracking, extra-dirty lignite coal.

Surrounded by such wild contradictions, most of us perform all sorts of mental tricks to try to reconcile the irreconcilable. Those scientists and environmentalists must be exaggerating, we tell ourselves. Or there must be more time before we

really need to change. Or maybe: the experts are just on the verge of figuring out a techno-fix. But does anyone really believe these fairy tales?

Sunday’s climate march will serve many purposes for its many participants: meet up, boost morale, exert political pressure. But sounding the alarm together will help us bring our actions in line with our emotions. So many of us are scared of what is happening to the world around us; for one day, we will come together and show it. Yes, we will be showing that sense of existential urgency to our politicians. But we will be showing one another.

By sounding this people’s alarm, we will also be saying that we are no longer waiting for politicians to declare climate disruption an emergency and respond accordingly. We are going to declare the emergency ourselves, from below, just as social movements have always done. The day after the march, many will be taking part in Flood Wall Street events, to draw clear connections between the logic of frenetic profit-making that rules financial markets and the collective failure to take the measures necessary to prevent runaway climate change.

The true leaders are not the ones who will show up at the United Nations next week in motorcades. The true leaders are the people next to us in the streets: the people who already achieved, and are fighting to defend, a moratorium against natural gas fracking in New York state. The Indigenous communities using their hard-won land rights to try to stop the suicidal expansion of the Alberta tar sands in Canadian court. The grassroots environmental justice groups in New York City that have been fighting the siting of toxic refineries and incinerators in the neighbourhoods for decades. And the students who have been demanding that their universities divest their endowments from fossil-fuel stocks, on the grounds that such businesses have made an immoral bet against all of our futures.

These are the people showing us what it looks like to act upon those terrifying warnings from climate scientists. To run away from the fire, instead of towards it.

Naming climate change as a clear and present danger is not a solution in itself, of course. But it is the critical first step. Forcefully expressing our collective sense of urgency will help us resist the next attempt to tell us that some manufactured economic imperative is more important than the stability of the planet – whether it’s the supposed need for more government austerity, or the need to grow the economy at any cost. That sustained sense of urgency will allow us to demand the kinds of bold action required to get off fossil fuels, and move to a regenerative economy, in the brief window we have left.

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