What a difference four years make. During the 2016 presidential debates, climate change got fewer than six minutes of airtime. In the lead-up to the 2020 race, Democratic candidates participated in a seven-hour climate town hall, a two-day climate forum hosted by MSNBC, and a Weather Channel special on the topic. Discussions of climate change are also cropping up in unexpected ways in races down the ballot. In a hotly contested election for Louisiana's agriculture commissioner, the Republican incumbent has had to defend his position on global warming, while in Texas, competitors for the state's powerful railroad commission are battling over how best to regulate emissions from the oil and gas industry.

During the last presidential election, about a third of voters said that climate change was "very important" in determining whom to vote for. By the beginning of 2020, polling by the Yale Program on Climate Change Communication showed that the number had shot up to 45 percent of registered voters. Research by the Environmental Voter Project found that voters who view climate and the environment as the top priorities are the most motivated to vote.

For the first time ever, we are hearing major presidential candidates talk about addressing climate change at the scale of the crisis. And there are folks running for seats at every level of government who are committed to making their city or state healthier, more resilient, and more sustainable.

This election represents a tremendous opportunity to set climate policy for the 2020s, the last decade in which we can avoid catastrophic warming. It's no exaggeration to say that this election may be the most important one we'll ever participate in.

Illustration by Montse Galbany

We are fast approaching the limits of our carbon budget—the amount of greenhouse gases we can put into the atmosphere and still stay within a 2.7ºF (or 1.5ºC) rise in global temperatures. That means we can't afford another four years of giveaways to the fossil fuel industry. Nor can we afford another four years of rollbacks of the safeguards meant to keep our air and water clean. And we can't afford four more years of attacks on the dignity of women, immigrants, people of color, and the LGBTQ community—or more assaults on the rule of law, voting rights, and our democracy.

Yes, I'm talking about beating Donald Trump. But we can't stop there. We need environmental champions at every level of government. We've seen how powerful climate leaders can be at the state and local levels. In 2018, for example, the Sierra Club supported then–US representative Michelle Lujan Grisham in her bid for governor of New Mexico. Once in the governor's office, Lujan Grisham signed the groundbreaking Energy Transition Act, which commits the state to run on zero-carbon energy by 2050.

The Sierra Club is investing more resources in this year's races than it has in any previous election. We're going all in—and to win, we need you. Make sure that you're registered to vote and that your friends, family, and neighbors are too. Get involved with the Sierra Club's volunteer field mobilization campaign—the largest in our 128-year history—and talk to voters about the issues that matter to you. In the coming months, we'll be rolling out a new online organizing platform on which you will find opportunities to canvass, text bank, phone bank, and attend events for Sierra Club–endorsed candidates.

In 2016, few of us expected that Donald Trump, a climate denier, would become president. But neither did we predict that by 2019, "climate emergency" would be Oxford Dictionaries' word of the year. Or that a 16-year-old Swedish schoolgirl would inspire a global climate strike. Or that more than 130 cities and seven states would commit to transitioning to 100 percent clean energy.

The good news is that the world is changing fast. But it needs to change even faster. In 2020, we have a chance to elect officials who will deliver the speed of change we need and the brighter, more sustainable future we deserve. Join the Sierra Club in making it happen.

Illustration by Montse Galbany

This article appeared in the May/June 2020 edition with the headline "Last Best Chance."