SCOTT SIMON, HOST:
The Environmental Protection Agency is updating its most important tool for trying to crack down on greenhouse gas emissions. That tool is a single number called the social cost of carbon. NPR's Rebecca Hersher reports the new number is simultaneously more accurate and an ethics nightmare.
REBECCA HERSHER, BYLINE: Imagine trying to add up all the human costs of emitting carbon dioxide into the atmosphere - the cost of lost crops and flooded homes and lost wages when people can't safely work outside, plus the cost of climate-related deaths. That is basically how the EPA figures out the social cost of carbon. And right now the official number is $51. The EPA wants to increase that to $190. Daniel Hemel is a law professor at New York University.
DANIEL HEMEL: So going from $51 to $190 - that's a move in the right direction.
HERSHER: The right direction, because most climate experts agree that the current number is too low. It underestimates the human cost of greenhouse gas emissions. A higher number would make it easier to do expensive things that cut emissions. For example, replacing all of America's power plants with renewable energy right away - that would be expensive. If the benefits to humanity are paltry, maybe it doesn't make sense. But if the benefits to humanity are really big then the government should do it. At least that's the idea. Tamma Carleton is a climate economist at the University of California, Santa Barbara. She says the social cost of carbon is the single most powerful climate policy tool that the federal government has.
TAMMA CARLETON: So we don't have other avenues for large-scale climate policy at the federal level. This is our main tool.
HERSHER: But the new number is controversial because of how the EPA is thinking about the lives that are lost from climate change. Noah Kaufman is a climate economist at Columbia University.
NOAH KAUFMAN: The question is how to put a value on those deaths.
HERSHER: Like, a dollar value - basically, how much is a life worth? Now, the EPA says on its website that they are not putting a dollar amount on human life. Instead, the agency says it, quote, "uses estimates of how much people are willing to pay for small reductions in their risks of dying." The EPA declined to answer NPR's questions for this story. Hemel says, in reality, the EPA's social cost of carbon does put a dollar amount on human lives.
HEMEL: You'll hear agencies say, we're not valuing lives. I don't know. They kind of are. They're deciding how much it's worth it to spend in order to save a life.
HERSHER: And because climate change is global, they're thinking about lives all around the world for the first time. That's one reason the new social cost of carbon number is higher. But not every death is being counted equally. The EPA uses higher dollar amounts for deaths in higher-income countries and lower dollar amounts for deaths in lower-income countries. Or, as Paul Kelleher, a bioethicist at the University of Wisconsin, puts it...
PAUL KELLEHER: The badness of a death from climate change in India is treated as not as bad as exactly the same death if it happened at exactly the same time in the United States.
HERSHER: According to the EPA's calculations, one climate-related death in the U.S. has about as much value as nine deaths in India, or five deaths in Ukraine, or 55 deaths in Somalia. Vaibhav Chaturvedi is a climate economist at the Council on Energy, Environment and Water, an influential climate think tank in New Delhi, India.
VAIBHAV CHATURVEDI: Anybody in the developing world would kind of probably think in this kind of way. It is inherently inequitable to use this sort of approach.
HERSHER: Chaturvedi says the U.S. government should put the same value on every life, morally, but also logically, because America's greenhouse gas emissions endanger people everywhere, and especially in low-lying and low-income countries where people are more vulnerable to rising seas and extreme weather. Hemel, the law professor, agrees.
HEMEL: I think we send a problematic message to Americans when we use a method for assigning values to lives outside the United States that ends up valuing light-skinned people from the Global North more than dark-skinned people from the Global South.
HERSHER: And there are practical implications as well. A recent study found that if the EPA assigned the same value to all lives, their newly proposed social cost of carbon would approximately double.
CHATURVEDI: That would mean the U.S. government will have to enhance the pace of action because now the cost of carbon would be much higher, the social cost will be much higher.
HERSHER: And the higher the social cost of carbon, Chaturvedi points out, the more incentive there is for the U.S. to reduce greenhouse gas emissions quickly, which would save more lives around the world. Kelleher is more blunt about the implications of the EPA's choice.
KELLEHER: Is a grave, moral mistake.
HERSHER: He says it's just not true that the lives of richer people are worth more.
KELLEHER: It's important to get it right because these are life and death decisions. Every molecule of carbon dioxide matters. Every ton of carbon dioxide matters. And so small changes in these dollar numbers - for example, the social cost of carbon - will make a big difference to who lives, who dies, how good their lives are, how bad their deaths are.
HERSHER: The EPA is accepting public comments on its proposed social costs of carbon until February 13.
Rebecca Hersher, NPR News. Transcript provided by NPR, Copyright NPR.
