One difficulty in explaining climate change to naysayers is the fact that so-called “global warming” isn’t always evident: Think of a congressman, a person in a position of power elected by the people to craft the laws that govern the land, bringing a snowball into the Capitol to refute climate change during a particularly chilly winter. But the reality is that climate change brings more extreme weather – at both ends of the spectrum – and according to experts in the U.K., several countries are at risk of “food shocks” because of it.

“The food system is increasingly under pressure because demand is growing and our ability to supply it is much more constrained. On top of that we have climate change affecting where we can grow things,” said Tim Benton, professor of population ecology at the University of Leeds and co-author of the report. If we are coping with demand increases by sustainable intensification but then suddenly we have a catastrophic year and lose a significant chunk of the world’s calories, everybody will feel it.”

A food shock is defined as production of the world’s four major crops – corn, soy, rice and wheat – dropping anywhere from 5-7%. Currently, that’s predicted to happen once every 100 years. But given the current strain on the food supply and increasingly extreme weather, the experts predict that it could happen as often as once per generation, roughly every 30 years.

Such food shocks would mostly affect developing countries, where supplies are already limited and weather tends to be even more extreme. But the authors are quick to note that the U.S. and U.K. would not emerge unscathed. Food is perhaps the most vital human need, so the instability and conflict created by a food shock would certainly involve developed nations.

They said that in the countries most affected by food shocks, the poorest households spend as much as 50% of their income on food. Should prices rise 50-100%, those people would be in a position the researchers call “untenable.”

The researchers also note that if climate change continues at its current rate, major food shocks – where crop yields fall by 10% or more – could become more common as soon as the year 2070.

It’s a wonderful time to be alive.