That gives businesses time and sends an immediate signal for the market to develop new, innovative solutions.

When you ask yourself what you can do to limit climate change, it’s natural to think of things like driving an electric car or eating less meat. This sort of personal action is important for the signals it sends to the marketplace—see the next section for more on that point—but the bulk of our emissions comes from the larger systems in which we live our daily lives. When somebody wants toast for breakfast, we need to make sure there’s a system in place that can deliver the bread, the toaster, and the electricity to run the toaster without adding greenhouse gases to the atmosphere. We aren’t going to solve the climate problem by telling people not to eat toast. But putting this new energy system in place requires concerted political action. That’s why engaging in the political process is the most important single step that people from every walk of life can take to help avoid a climate disaster. In my own meetings with politicians, I’ve found that it helps to remember that climate change isn’t the only thing on their plate. Government leaders are also thinking about education, jobs, health care, foreign policy, and more recently, COVID-19. And they should: All those things demand attention. But policy makers can take on only so many problems at once. And they decide what to do, what to prioritize, based on what they’re hearing from their constituents. In other words, elected officials will adopt specific plans for climate change if their voters demand it. Thanks to activists around the world, we don’t need to generate demand: Millions of people are already calling for action. What we do need to do, though, is to translate these calls for action into pressure that encourages politicians to make the tough choices and trade-offs necessary to deliver on their promises to reduce emissions. Whatever other resources you may have, you can always use your voice and your vote to effect change. Make calls, write letters, attend town halls. What you can help your leaders understand is that it’s just as important for them to think about the long-term problem of climate change as it is for them to think about jobs or education or health care. It may sound old-fashioned, but letters and phone calls to your elected officials can have a real impact. Senators and representatives get frequent reports on what their offices are hearing from constituents. But don’t simply say, “Do something about climate change.” Know where they stand, ask them questions, and make clear that this is an issue that will help determine how you vote. Demand more funding for clean energy R&D, a clean energy standard, or a price on carbon, for example. Look locally as well as nationally. A lot of the relevant decisions are made at the state and local levels by governors, mayors, state legislatures, and city councils—places where individual citizens can have an even bigger impact than at the federal level. In the United States, for example, electricity is primarily regulated by statewide public utility commissions, made up of either elected or appointed commissioners. Know who your representatives are and keep in touch with them. Run for office. Running for the U.S. Congress is a tall order. But you don’t have to start there. You can run for state or local office, where you’ll probably have more impact anyway. We need all the policy smarts, courage, and creativity in public office that we can get. As a Consumer The market is ruled by supply and demand, and as a consumer you can have a huge impact on the demand side of the equation. If all of us make individual changes in what we buy and use, it can add up to a lot—as long as we focus on changes that are meaningful. For example, if you can afford to install a smart thermostat to reduce your energy consumption when you’re not at home, by all means do it. You’ll cut your utility bill and your greenhouse gas emissions. But reducing your own carbon emissions isn’t the most powerful thing you can do. You can also send a signal to the market that people want zero-carbon alternatives and are willing to pay for them. When you pay more for an electric car, a heat pump, or a plant-based burger, you’re saying, “There’s a market for this stuff. We’ll buy it.” If enough people send the same signal, companies will respond—quite quickly, in my experience. They’ll put more money and time into making low-emissions products, which will drive down the prices of those products, which will help them get adopted in big numbers. It will make investors more confident about funding new companies that are making the breakthroughs that will help us get to zero.