Cars piled on top of each other in a garage in Lower Manhattan on Oct. 31, 2012, after Hurricane Sandy. (Stan Honda/AFP/Getty Images)

For New Yorkers, late October 2012 was a moment when something fundamental altered. If there were any climate change deniers in the five boroughs before Hurricane Sandy, I don’t think there were too many left afterward. Forty-four lives taken; flood, fire, stretches of our electrical grid blacked out; and around $19 billion in homes, businesses and infrastructure damaged.

New York City stared climate change in the face then. And now, we’re doing something about it. We understand that climate change is an existential threat, but we do not accept that it is inevitable. We know many of our national leaders are in denial, but we will not wait for their help. Together, New Yorkers have a loud voice and deep pockets, and we intend to use them.

America’s largest city, 8.5 million strong, is taking decisive action on two separate fronts. We are demanding compensation from those who profit from climate change. And we plan to withdraw our formidable investment portfolio from an economic system that is harmful to our people, our property and the city we love and invest it in more productive ways.

This week, the City of New York filed a lawsuit in federal court against the five investor-owned fossil fuel companies: Exxon, BP, ConocoPhillips, Shell and Chevron. We are seeking billions of dollars in damages from these giants because they are central actors in this crisis. We’re proud to join cities like San Francisco, Oakland and Santa Cruz in taking on Big Oil in court.

Hurricane Sandy might have been covered on the Weather Channel, but volatile storms like that aren’t simply weather. For decades, Big Oil ravaged our environment. They knew what they were peddling was lethal, but they didn’t care. They used the classical Big Tobacco playbook of denial, denial, denial, and all the while they did everything to hook society on their lethal product.

Have they been punished for it? No. In fact, they’ve made trillions.

Think how cynical that is. Then take a look around you at the results. Swaths of California have gone up in flames. We are seeing snow in Florida. The Arctic ice is melting. The island of Puerto Rico, so important to us as New Yorkers — our sixth borough — is still reeling from Hurricane Maria.

Today, we are saying, “No more.” The time is long past due for Big Oil to pay the bill and take full responsibility for the devastation they have wrought. That by itself will be a major step forward, but it isn’t enough. We know we have more to do. We are going to stop investing in the fuel of yesterday, so we can have a better tomorrow.

The City of New York, its pension funds and the entities that control those funds are working to agree to divest from approximately 190 companies that own fossil fuel reserves. In total, the sum of investments we intend to divest adds up to around $5 billion. No other large city and no other state in this union has taken this action yet. We will be the first, but we hope we aren’t the last. And I want to be clear about something: There is no contradiction between making wise investments for our people and our pensioners and protecting the planet they live on.

We take these two groundbreaking steps now, but they are by no means the first steps we have taken in this fight. We are already committed to a series of ambitious projects aimed at lowering our emissions and creating a livable environment for the New Yorkers of tomorrow.

We will reduce the emissions our city produces by 80 percent by 2050. We will honor the Paris agreement to limit any temperature increase in the world to no more than 1.5 degrees Celsius. We will demand that the most-polluting large buildings in the city, which are responsible for 24 percent of all our greenhouse emissions, lower their output or face major fines.

We will build a city that is more resilient in the face of rising waters and more powerful storms.

One thing I always try to get across to people is that this is a battle that never ends. It’s not like there is going to be a day when we can say, “We’re done. Climate change has ended.” Maybe some place in a distant future that moment will occur, but not for you and me. This is a fight that we will have to continue to wage, and we shouldn’t be afraid of that.

We know we’re going to face opposition. We know powerful interests and cynical people will push back and hard. But we also know New York City has a special responsibility. We are a beacon to the world. People watch us. We didn’t choose this battle, but we accept it willingly. We have to get it right and show what can be done.

If you are a state, a city, a town or an employer, I hope you’ll join us. The time has come to fight as if our lives depend on it. Because they do.

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