EXPLAINER: Can climate change be solved by pricing carbon?

BILLINGS, Mont. (AP) — As climate change bakes the planet, dozens of nations and many local governments are putting a price tag on greenhouse gas emissions that are increasing flooding, droughts and other costly catastrophes.

Pennsylvania on Saturday becomes the first major fossil fuel-producing state in the U.S. to adopt a carbon pricing policy to address climate change. It joins 11 states where coal, oil and natural gas power plants must buy credits for every ton of carbon dioxide they emit.

President Joe Biden is attempting a less direct approach — known as the social cost of carbon — that calculates future climate damages to justify tougher restrictions on polluting industries. Republicans say that could crush many businesses. They want the U.S. Supreme Court to stop the administration after lower courts in Louisiana and Missouri split on the issue.

Governments elsewhere have moved more aggressively. Canada, for example, imposes fuel charges on individuals and also makes big polluters pay for emissions. It's one of 27 nations with some kind of carbon tax, according to The World Bank.

The varied strategies come as scientists warn climate change is accelerating — and all can help reduce emissions. But experts say U.S. efforts have been hobbled by its fractured approach.

“Part of the reason you need all of these things to work in tandem is we do not have a federal climate policy," said Seth Blumsack, director of the Center for Energy Law and Policy at Penn State University. “We have social cost of carbon used in regulatory decisions but not (a carbon price) that is faced by the market.”

SO WHAT'S THE PRICE TAG?

It varies. A lot.

The Biden administration's social cost estimate is about $51, meaning every ton of carbon dioxide spewed from a power plant or tail pipe...