In the absence of an official Democratic debate about climate-change policy, CNN hosted a seven-hour town hall on the subject this week with 10 Democratic presidential candidates.

Each candidate got 40 minutes to discuss their ideas about how the US should tackle the climate crisis and answer questions from the audience.

Nearly all of said that the US should recommit to the Paris climate agreement (President Donald Trump has pledged to withdraw the US from the agreement as soon as it’s legally permitted in November 2020) and halt new leases for oil and gas drilling on public lands. Most also offered a plan to put a price on carbon emissions.

The discussions also covered issues like fracking – the process of injecting rock with high-pressure liquid to release natural gas – whether to offer federal assistance to Americans displaced by climate change, and nuclear power (which currently accounts for 20% of US electricity).

Senator Elizabeth Warren, who recently incorporated many elements of former candidate Jay Inslee's climate plan into her own, pushed for the US to achieve 100% clean energy in just a decade. Others, like Senator Kamala Harris, advocated for a sweeping Green New Deal.

Businessman Andrew Yang, meanwhile, expounded on his support for geoengineering efforts like seeding clouds with aerosols to reflect sunlight back into space. And Senator Bernie Sanders talked about the idea that controlling population growth could be a climate-change strategy.

Read More: Bernie Sanders said birth control can help fight climate change. Here's why it's such a thorny issue.

Each candidate has a plan - with budgets of trillions of dollars - to help save the planet from the potentially catastrophic consequences of the climate crisis.

Here's a brief overview of where each of the 10 candidates (ordered alphabetically by last name) stand on important climate-related issues like carbon taxes, offshore drilling, and a net-zero carbon economy.


"If we did everything perfectly, everything — and we must and should in order to get other countries to move — we still have to get the rest of the world to come along," Joe Biden said.

Foto: 2020 Democratic presidential candidate and former Vice President Joe Biden speaks in Des Moines, Iowa on August 10, 2019.sourceScott Morgan/Reuters

Price on carbon emissions: Supports a carbon tax.

Net-zero carbon emissions: By 2050.

Nuclear energy: Willing to leave it on the table as an energy option. Biden's climate plan includes support for research into nuclear-waste disposal systems.

Green New Deal: He said he's "not opposed to it" and that it "deserves an enormous amount of credit." But Biden noted that the plan lacks details about how to achieve its aims.

Fracking: Biden opposes opening up federal lands to new natural-gas drilling, but doesn't support a full fracking ban.

Offshore drilling: "Pursue a global moratorium."

Highlights from his session:

Biden was forced to defend his planned attendance of a fundraiser organized by Andrew Goldman, co-founder of the natural gas company Western LNG. Biden had pledged not to take any money from the fossil fuel industry.

"He's not a fossil fuel executive," Biden said, adding: "I was told by my staff he doesn't have any responsibility related to the company ... If that turns out not to be true, then I will not, in any way, accept his help."

Biden's climate plan can be found here.

Cost: $1.7 trillion.


"Climate is not a separate issue,” Cory Booker said. “It is the lens through which we must do everything."

Foto: 2020 Democratic presidential candidate Cory Booker addresses an audience at the annual NAACP convention in Detroit, Michigan on July 24, 2019.sourceRebecca Cook/Reuters

Price on carbon emissions: Booker told the New York Times that "a federal price on carbon should be one part of a comprehensive response to the threat of climate change."

Net-zero carbon emissions: By 2045.

Nuclear energy: He's very much in favor of it - people who think it's possible to get to net-zero carbon emissions without nuclear energy "just aren't looking at the facts," Booker said.

Green New Deal: One of the first steps in Booker's climate plan is to "work to implement a Green New Deal."

Fracking: Supports banning fracking on public lands.

Offshore drilling: Ban it.

Highlights from his session:

Booker compared to climate crisis to the urgency of the Civil Rights movement, and said he supports banning fossil-fuel exports from the US.

When asked about his support for geoengineering, he waffled. "I have to say, I don't know if it's cheating or not," he said.

Booker's full climate plan can be found here.

Cost: $3 trillion.


"This is the hardest thing we will have done certainly in my lifetime as a country," Pete Buttigieg said. "This is on par with winning World War II, perhaps even more challenging than that."

Foto: Democratic presidential candidate and Mayor of South Bend, Indiana Pete Buttigieg campaigns in San Francisco, California, June 1, 2019.sourceREUTERS/Stephen Lam

Price on carbon emissions: Supports a carbon tax. "I know you're not supposed to use the T word when you're in politics, but we might as well call this what it is," Buttigieg said.

Net-zero carbon emissions: No later than 2050.

Nuclear energy: In an April interview with the Boston Herald, Buttigieg said,"nuclear has problems, but it has the advantage that it does not create carbon emissions, so if we got to choose our pros and cons, I think that nuclear certainly is preferable to anything like coal."

Green New Deal: The first step of his climate plan is "implement a bold and achievable Green New Deal."

Fracking: "I favor a ban on new fracking and a rapid end to existing fracking," he said.

Offshore drilling: End it.

Highlights from his session:

Buttigieg took a moment to describe the climate crisis in a "language that is understood across the heartland about faith":

"You know, if you believe that God is watching as poison is being belched into the air of creation, and people are being harmed by it, countries are at risk in low lying areas, what do you suppose God thinks of that?" he said.

Buttigieg's full climate plan can be found here.

Cost: $1.5-2 trillion.


Julián Castro said "we don't need climate scientists to tell us what we see with our own eyes," pointing to climate-related disasters like Hurricane Dorian and Arctic melting.

Foto: Julian Castro speaks at the Texas Democratic Convention in Fort Worth, Texas on June 22, 2018.sourceRichard W. Rodriguez, File via AP

Price on carbon emissions: Wants a carbon-pollution fee for the "biggest ... industrial scale polluters." He did not name any examples of "corporate polluters" when asked during the town hall.

Net-zero carbon emissions: By 2045, with a push to get the rest of the world to net zero by 2050.

Nuclear energy: According to the Washington Post, Castro said he would not support building any new nuclear plants.

Green New Deal: "We're gonna say no to subsidizing big oil and say yes to passing a Green New Deal," he tweeted in January.

Fracking: "I support local communities and states that want to ban fracking. I have not called for an immediate ban on fracking," he said. In 2011, when he was mayor of San Antonio, Texas, Castro touted the economic benefits of fracking.

Offshore drilling: End it.

Highlights from his session:

Castro has made environmental justice a top priority in his climate plan. "The problem is that, like our neighborhoods, pollution is segregated," his plan states.

In the town hall, he said: "Oftentimes the first folks to get flooded out are the poorest communities. They're often communities of color. They're the ones that can least afford to deal with the climate crisis."

Castro's full climate plan can be found here.

Cost: $10 trillion.


"I would sue Exxon Mobil," Kamala Harris said.

Foto: Democratic presidential candidate and Senator Kamala Harris speaks at a campaign party in Gilford, New Hampshire, July 14, 2019.sourceREUTERS/Brian Snyder

Price on carbon emissions: Supports a "progressively increasing fee" on carbon pollution.

Net-zero carbon emissions: By 2045.

Nuclear energy: Harris said the biggest issue with nuclear energy is "the waste and what are we going to do with that." But she added that she'd leave decisions about how to deal with nuclear energy and waste to states.

Green New Deal: Yes. If Congress fails to act, Harris said, "I am prepared to get rid of the filibuster to pass a Green New Deal."

Fracking: Ban it, starting with public lands.

Offshore drilling: Ban it.

Highlights from her session:

Harris was the only candidate who voiced support for getting rid of the Senate filibuster to pass a Green New Deal.

She also said she'd declare the drinking-water crisis a national emergency.

Harris' full climate plan can be found here.

Cost: $10 trillion


"We can’t build a green economy that leaves anyone behind," Amy Klobuchar said.

Foto: Senator Amy Klobuchar during a Senate Judiciary Committee hearing on Capitol Hill in Washington DC, January 15, 2019.sourceAP Photo/Carolyn Kaster

Price on carbon emissions: Klobuchar wants to wait and "see who we have in Congress and how far we can move" before opting for a carbon tax.

Net-zero carbon emissions: By 2050.

Nuclear energy: Does not support building new nuclear plants "unless we can find safe storage."

Green New Deal: Yes. "I'm a co-sponsor of the Green New Deal," she said.

Fracking: Klobuchar doesn't support banning fracking because she sees natural gas as "a transitional fuel" that "is better than oil, but it's not nearly as good as wind and solar." However, she vowed to "review every fracking permit there is" during her first 100 days as president.

Offshore drilling: Ban it.

Highlights from her session:

Klobuchar said she wants to restore the Clean Power Plan, an Obama-administration policy that set certain carbon-emissions standards.

Klobuchar also said she is "strongly in favor of the Endangered Species Act ... and I would do anything to reverse some of the suggestions that the president has made recently to repeal it or to water it down."

Klobuchar's full climate plan can be found here.

Cost: $2-3 trillion


"I'm asking Americans to make this our priority as a country," Beto O'Rourke said of solving the climate crisis.

Foto: 2020 Democratic presidential candidate Beto O'Rourke speaks at the NAACP's National Convention on July 24, 2019 in Detroit, Michigan.sourceJeff Kowalsky/Getty

Price on carbon emissions: O'Rourke supports a cap-and-trade approach in which the financial cost of emissions fluctuates with the market.

Net-zero carbon emissions: By 2050.

Nuclear energy: Has not provided an answer yet.

Green New Deal: "Some will criticize the Green New Deal for being too bold or being unmanageable. I tell you what, I haven't seen anything better that addresses this singular crisis we face," he said in a March interview.

Fracking: Last year, O'Rourke told the Midland Reporter-Telegram that fracking is "fundamental to national security." He added, "I'd much rather they burn natural gas from Texas that's connected to jobs here. It's connected to a much cleaner way to produce energy than coal."

Offshore drilling: End it. (However, in April, O'Rourke voted to kill an anti-drilling amendment that would have prohibited "the use of funds being used to research, investigate, or study offshore drilling in the Eastern Gulf of Mexico.")

Highlights from his session:

O'Rourke said he wants to fully fund disaster-response agencies like FEMA.

"I hope it makes everybody angry the way that we've treated the people of Puerto Rico - our fellow Americans who were left in harm's way without the necessary investment in the infrastructure to mitigate the storms that we knew were going to hit them," he said.

He added that he would provide federal assistance to people who want to move out of flood-prone areas like Houston, Texas.

O'Rourke's full climate plan can be found here.

Cost: $5 trillion


"Donald Trump thinks that climate change is a hoax. I think he is dangerously, dangerously wrong," Senator Bernie Sanders said.

Foto: Senator Bernie Sanders speaks at a campaign rally in Dover, New Hampshire, on September 1, 2019.sourceBrian Snyder/Reuters

Price on carbon emissions: Sanders' climate plan states that he will "make the fossil-fuel industry pay for their pollution" by "massively raising taxes on corporate polluters' and investors' fossil-fuel income and wealth." Sanders has previously argued that a carbon tax "must be a central part of our strategy for dramatically reducing carbon pollution."

Net-zero carbon emissions: By 2050.

Nuclear energy: Sanders is against nuclear power. His campaign website says: "We must stop building new nuclear power plants, and find a real solution to our existing nuclear waste problem."

"It doesn't make a whole lot of sense to me to add more dangerous waste to this country and the world when we don't know how to get rid of what we have now," he said at the town hall.

Green New Deal: Sanders supports a version of it that would "create up to 20 million good-paying jobs over the period of 15 years."

Fracking: He has pushed for a fracking ban on public lands.

Offshore drilling: Ban it.

Highlights from his session:

When asked about whether curbing population growth was a "reasonable" plan to address climate change, Sanders suggested that improving access to birth control and increasing women's reproductive rights could indeed help.

He also said he would not give federal assistance to Americans seeking to rebuild their homes after natural disasters.

Sanders' full climate plan can be found here.

Cost: $16 trillion (Sanders' climate plan is the most expensive and most ambitious of the 10 candidates.)


"They want to be able to stir up a lot of controversy around your lightbulbs, around your straws, and around your cheeseburgers," Elizabeth Warren said of the fossil-fuel industry.

Foto: Democratic presidential candidate Elizabeth Warren makes a visit to Fairfield, Iowa, on May 26, 2019.sourceReuters/Rachel Mummey

Price on carbon emissions: Supports a carbon tax.

Net-zero carbon emissions: Wants the US to cut 70% of carbon emissions by 2035 via changes to buildings, transportation, and electricity systems. "The other 30% we still got to work on," she added.

Nuclear energy: Wants the US to stop using it by 2035.

Green New Deal: Yes. Warren thinks one of the best parts of the proposal is that it both helps the planet and "is about worker justice" and "justice for people whose communities have been destroyed."

Fracking: Supports a nation-wide fracking ban.

Offshore drilling: "On my first day as president, I will sign an executive order that says no more drilling  -  a total moratorium on all new fossil fuel leases, including for drilling offshore and on public lands," Warren said.

Highlights from her session:

Much of Warren's climate plan echoes the one put forward by Jay Inslee, who dropped out of the presidential race last month.

Warren has broken down her timeline for carbon emissions reductions by industry. She wants commercial and residential buildings to emit no carbon emissions by 2028, and cars, trucks, and buses to emit zero carbon by 2030.

Warren's plan to ban fossil-fuel leasing on public lands can be found here.

Her plan for "green manufacturing" can be found here.

Her plan to use the military to help fight climate change can be found here.

Her plan for transitioning to clean energy can be found here.

Cost: $3 trillion


Of his support for geoengineering, Andrew Yang said: "In a crisis, all solutions have to be on the table. So, if you are attacking on one side, you also should be researching various alternatives on the other."

Foto: Businessman Andrew Yang during his visit to Business Insider's New York offices.sourceHollis Johnson/Business Insider

Price on carbon emissions: A carbon tax that starts at $40 per ton then ramps up to $100 per ton, "because we need to have polluters internalize the cost of their pollution." Yang said this gradual increase would "give them time to adjust."

Net-zero carbon emissions: In the next 30 years.

Nuclear energy: "Needs to be on the table in a transition to a more renewable economy," Yang said.

Green New Deal: Yang said he loves the "vision" but doesn't think it's possible to make the US carbon neutral within a decade.

Fracking: Not mentioned in his climate plan, and he didn't touch on it at the town hall, either.

Offshore drilling: Ban it.

Highlights from his session:

Yang said his proposed "freedom dividend" - a monthly allowance of $1,000 for every American - would help climate refugees flee or protect themselves from natural disasters.

He also emphasized his support for geoengineering technologies like space mirrors and cloud seeding.

Additionally, he proposed a constitutional amendment to make it "the responsibility of the United States government to safeguard and protect our environment for future generations."

Yang's climate plan can be found here.

Cost: $5 trillion