The past few weeks in the United Kingdom have brought a steady stream of ominous food headlines: Beer is being rationed! (In the middle of the World Cup, no less!) Barbecues might run out of meat! Bakeries have stopped making crumpets! And then our own Yasmeen Serhan checked in for a flight from Europe to find there would be no ice cream.

What all of the above have in common is carbon dioxide. Carbon dioxide makes beer fizzy. It’s used to stun animals before slaughter. It keeps meat and crumpets fresh in their packaging by displacing oxygen. Frozen solid into dry ice, it keeps ice cream cold. And as absurd as it may sound when CO 2 is rising in the atmosphere, Europe has been suffering a carbon-dioxide shortage—the “worst supply situation to hit the European carbon-dioxide (CO 2 ) business in decades,” according the industry publication Gasworld.

The culprit? Ammonia fertilizer. And once you tug at the reason Europe is experiencing a carbon-dioxide shortage, you start to unravel the entangled supply chains of modern food production.