Environmental activists found many insightful answers from candidates during CNN’s 7-hour-long climate crisis town hall on Sept. 4. The event was held in spite of DNC leadership’s initial rejection the Sunrise Movement’s demand for a single issue presidential debate on climate change.The most substantive discussion on climate held so far in the democratic presidential contest, the leading 10 candidates for the nomination took turns on stage.

Each of the candidates had the opportunity to speak for around 35 minutes. They discussed plans, positions and points of view that we likely never would have learned without the forum. Here are the highlights from that night:

Andrew Yang (D) was the first on stage and delivered a strong performance by going after major environmental polluters. The entrepreneur committed to eliminating all subsidies to fossil fuel companies and add condemnation for the way they’ve been spending it: “You know how they’ve been spending some of their money, their billions of dollars in profit? On a misinformation campaign to the American people, and they’ve taken our legislature hostage,” he said. Critiques weren’t just directed at the oil companies, either. “Certainly meat is an extraordinarily expensive thing to produce from an environmental sustainability point of view,” Yang added.

Cory Booker (D-N.J.) broke with traditional liberal viewpoints on nuclear power. “And right now nuclear is more than 50% of our non-carbon causing energy, so people who think that we can get [net-zero carbon emissions] without nuclear being part of the blend just aren’t looking at the facts,” Booker said. He went on to describe Chernobyl and Fukushima as a history of older generation plants that were less safe and, unlike next generation nuclear, didn’t recycle spent nuclear fuel rods.

Julian Castro (D)* introduced issues of power and justice to the town hall discussion: “Often times, it’s people who are poor, communities of color who take the brunt of storms that are getting more frequent and more powerful. And so, my plan actually calls for new civil rights legislation to be able to address environmental injustice,” he said.

Pete Buttigieg’s (D-South Bend, I.N.) approach to climate change centers on a carbon tax: “There is a harm being done, and in the same way that we have taxed cigarettes, we’re going to have to tax carbon. Now the difference with my plan is that I propose that we rebate all of the revenue that we collect right back out to the American people on a progressive basis so that low and middle-income Americans are made more than whole,” he said.

Beto O’Rourke (D)* favored a different approach to taxing carbon: “I think the best possible path to do that is through a cap and trade system. There would be allowances granted or sold to polluters, not just in the energy sector but in transportation as well as our industrial sector––cement, steel, the chemicals that we produce. There would be a set number of allowances that would decrease every single year, because the clock is running; we have a little more than 10 years left,” he said. 

Since Washington Governor Jay Inslee dropped out of the race and announced his climate change plans were open for other campaigns to adopt, multiple candidates have shown interest. 

Elizabeth Warren (D-M.A.) adopted many of Inslee’s ideas in her new climate change plan that targets 3 major carbon polluters. “So what I’ve adopted is, by 2028, we don’t have any more new building that has any carbon footprint. By 2030, we do the same thing on vehicles, on our cars and light-duty trucks. And by 2035, we do the same thing on electric generation,” she said. “That will cut 70% of the carbon that we are currently spewing into the air.”

Bernie Sanders (D-V.T.) proposed the largest spending plan—$16.3 trillion—to combat climate change. His contribution to the conversation wasn’t simply a massive spending approach, but a uniting of countries around the world to act on climate change. He urged that America reach out to China, Russia, India and others for common cooperation. Sanders added, “And maybe, just maybe, instead of spending $1.5 trillion every single year on weapons of destruction, designed to kill each other, maybe we pool those resources and we work together against our common enemy, which is climate change.”

Kamala Harris (D-C.A.)* suggested that climate change could be tackled with lawsuits, fines and fees against polluting companies. One of her more controversial proposals during the town hall was to eliminate the filibuster if the Congress failed to act on climate change. “I was part of a committee hearing during which the underlying premise of the hearing was to debate whether science should be the basis of public policy, this on a matter that is about an existential threat to who we are as human beings,” she explained.

Former Vice President Joe Biden explained the value of a diplomatic, consensus-building stance at home and abroad to fight climate change. He also warned viewers of climate change dangers and damages to military bases that help keep us secure. “First thing that happened when the president—when President Obama––and I were elected, we went over to what they call—and some of you are military women and men—over to the tank in the Pentagon, sat down and got the briefing on the greatest danger facing our security. You know what they told us it was, the military? Climate change. Climate change. The single greatest concern for war and disruption in the world, short of a nuclear exchange immediately,” he said.

One of the major points that Amy Klobuchar (D-M.N.) stressed was bringing back the methane rules that President Trump has deregulated. Yet for me, her remarks about bi-partisan support for energy efficiency were the most insightful. “There are just numerous examples of what we can be doing to make energy efficiency, which I agree is this low-hanging fruit. You know why it’s popular with the public? Whether it’s increasing the gas mileage standards and then eventually moving to electric cars, or the building standards, or the appliance standards—it’s popular because if people save money they really like it,” she said.

All these issues and more cited during the CNN town hall only further highlight the need for the presidential candidates to resolve amongst themselves, on the prime-time debate stage, which candidate is best on the issue. Climate change is a clear and present danger that demands the highest attention of whoever takes the oval office. It is critical that both the candidates and the voters fully debate such issues now, so the nation can enact the best climate change policies following the 2020 election.

* Editor’s note: Since the writing of this piece, O’Rourke, Harris and Castro have withdrawn from the presidential race.