Carbon dioxide is the leading cause of climate change. But when the U.K. experienced a shortage of CO2 last year, it drove consumer fears of higher prices for food and drink. At the heart of this paradox is that, for all the damage that CO2 does, it also has some essential uses in modern society.
If you get contact-traced because you've been near someone infected with a contagious disease, it’s too late to protect yourself. You isolate to protect others. But a new app aims to fight outbreaks using our desire to protect ourselves. Here's how.