CNN's Wolf Blitzer just asked Andrew Yang if he supports a carbon tax.
"I do support a carbon tax — if you went to my website, Wolf, you would know this," Yang said as the audience laughed.
Yang said his carbon tax would start at $40 per ton, and go up to $100 per ton.
How does a carbon tax work, anyway? Many people think the most effective way to drastically cut carbon emissions would be to set a price on them — essentially, to tax them.
In 2010, Democrats in the House of Representatives passed a so-called "cap and trade" bill. It would have capped carbon emissions for businesses and forced emitters to buy credits for emissions from other businesses — that’s the trade part — but it never went anywhere in the Senate.