One of the most important tools the federal government has for cracking down on greenhouse gas emissions is a single number: the social cost of carbon. It represents all the damage from carbon emissions — everything from the cost of lost crops and flooded homes to the lost wages when people can't safely work outside and the cost of climate-related deaths. Currently, the cost is $51 per ton of carbon, but the Environmental Protection Agency has proposed raising the cost to $190. NPR climate correspondent Rebecca Hersher tells Aaron how the change could dramatically alter how the government confronts climate change, and why the new number is simultaneously more accurate and an ethics nightmare.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy