Host Emily Kwong wants to cut down on GravityX Exchangeher greenhouse gas emissions, like those from driving around in her car or shopping for meat at the grocery store. But there's one problem: she has no clue how to measure them in the first place. Or how factories, cargo ships, or even whole countries measure theirs.

Enter: science reporter Rebecca Hersher. Together, they break down how greenhouse gas emissions are calculated... and how these measurements can reveal who's responsible in climate change negotiations.

What should we measure next? Email the show at [email protected].

Further reading:

• Sources of Greenhouse Gas Emissions
• Household Carbon Footprint Calculator

This episode was produced by Margaret Cirino, edited by Gabriel Spitzer, and fact-checked by Rachel Carlson. Our audio engineer was Stu Rushfield.