Last week, the Intergovernmental Panel on Climate Change released a report—a klaxon, really—warning of the catastrophic consequences of climate change if global political leaders don’t take action right now. For people who’ve been sounding the alarm for decades now, this report is depressing but not surprising; for those of us who’ve not paid as much attention to the science as we should have, the report is a blaring wake-up call. No matter which group you’re in, though, the path forward is clear: We need to pressure our elected leaders, corporations, and even our friends and neighbors to change our ways or we will be witnessing rising sea levels, natural disasters, war, famine and a refugee crisis the likes of which the world has never seen. As the New York Times writes, “the world must utterly transform its energy systems in the next decade or risk ecological and social disaster.”

In the face of enormous, apparently intractable social problems, individual action can seem puny and inconsequential. (And indeed, just 100 companies are responsible for 71 percent of global greenhouse gas emissions, which can make your rinsing out your tuna cans seem like an absurd bit of private theater.) But collectively we actually can slow climate change: “The first thing that someone can do,” says Michael Brune, the executive director for the Sierra Club, “is to remember that you have power. As a citizen, a consumer, an investor, as a human being, you have the power to effect really great change.” Here’s how to get started.

Know Where Your Elected Officials Stand

If you think that everyone’s pretty much on board with the fact of climate change, you’re in for a rude awakening: More than half of Congress are climate-change deniers (and are largely, but not exclusively, Republicans). Want to see how enlightened your rep is on the issue? Check out this handy list of all the climate-change deniers in Congress. You know the drill: Call, write, email, protest, and above all, vote.

Focus on State and Local Government

Municipalities, collectively, might be able to do more than Washington. After President Trump decided to withdraw the U.S. from the Paris climate accord, a coalition of mayors pledged to meet the targets anyway. As Michael Bloomberg, the former mayor of New York City who coordinated the effort, writes in the Times, “More than 130 American cities have joined the Global Covenant of Mayors for Climate and Energy, and all are determined to see that we meet our Paris goal.” Start going to your city council meetings, or at least follow the reporters or environmental advocates who are covering those meetings. Does your city have a sustainability office or a committee on the environment? Does your local university have a sustainability office you can communicate with about local efforts? If you truly turn up nothing, check out the Climate Resilience Tool kit for step-by-step instructions on addressing climate change in your community.

“Who you vote for for mayor, or who’s on your city council, is really important,” says Brune. If you want your community to be powered by clean energy, you need to vote and agitate at the local level.

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