This article is from The Spark, MIT Technology Review's weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here. For the last week or so, I've been obsessed with a gas that I'd never given much thought to before. Sulfur hexafluoride (SF6) is used in high-voltage equipment on the grid. It's...

This is today's edition ofThe Download,our weekday newsletter that provides a daily dose of what's going on in the world of technology. A brief guide to the greenhouse gases driving climate change Sulfur hexafluoride (SF6) is used in high-voltage equipment on the grid. It's also, somewhat inconveniently, a monster greenhouse gas. Greenhouse gases are those...