The takeaways from 2020 Democrats' marathon CNN climate town hall

2020 Democratic White House hopefuls talked about climate change for roughly 7 hours last night in a CNN town hall — where it became clear that the whole landscape has shifted on the topic.

Why it matters: The network was past asking if candidates believe in human-induced warming. The first question to Joe Biden was about whether his plan for achieving net-zero emissions by 2050 is too weak, highlighting just how much the center of gravity on the left has moved in recent years.

• The event captured the vast dimension of the problem, going way beyond coal and cars to touch on farming, industry, human migration, adaptation, deforestation, trade, the food system, racial and economic justice dimensions of climate — and much, much more.

Some of the biggest takeaways from the event...

Kamala Harris said Senate Democrats should kill filibuster rules if Republicans didn't work with her on a sweeping climate bill. The California senator had previously been more equivocal.

• Big climate legislation faces immense hurdles even if Democrats regain a narrow Senate majority thanks to the 60 votes needed to move bills.

Elizabeth Warren announced support for a carbon tax as part her much wider plan, but offered no real detail. She'd previously signaled overall support for carbon pricing but in blander terms.

• Warren also added clarity to her stance on nuclear power. She opposes building new nuclear plants and called for "weaning ourselves off nuclear energy" too.

Biden was put on the defensive, facing on-air questions about a fundraiser he plans to attend Thursday hosted by Andrew Goldman, co-founder of the natural gas company Western LNG.

• Biden is among many candidates who signed a pledge not to take money from fossil-fuel executives.
• Biden said that Goldman isn't listed as an executive in SEC filings. And the campaign said he's not involved in day-to-day operations, which CNN's Anderson Cooper noted on-air too.

• But the episode won't help Biden among liberal activists who are already wary of his campaign and climate posture.

Jay Inslee's campaign lives on. Several candidates — Warren, Harris, Julián Castro and Amy Klobuchar — all approvingly name-checked Inslee's ideas.

There are real differences between the candidates. Underneath their vows to act aggressively, the event laid bare divides over varying topics:

• Nuclear power: "People who think we can get there without nuclear being part of the blend just aren’t looking at the facts," Sen. Cory Booker said.
• Fracking and natural gas: Some candidates backed a ban on fracking. Harris said there's "no question I’m in favor" of one, but Klobuchar didn't go nearly that far — nor did Castro.
• Carbon pricing: Warren endorsed a tax, and Beto O'Rourke came out in favor of a cap-and-trade system, but specifics were in short supply overall.

Go deeper: What you need to know about each candidate's performance last night