In the wake of last year’s awful hurricane season, we heard a lot about how global warming may jeopardize human lives through apocalyptic storms and freak weather. But it turns out there’s actually a much more direct threat to our health from global warming. It’s the warming part.

According to an article in the New York Times:

Heat is the single largest natural killer of Americans in the continental United States, causing the death of 175 people in an average year, the agency said—more than lightning, hurricanes, tornadoes, floods or earthquakes.

A heat wave in 1995 killed 735 people in Chicago. And a 2003 heat wave killed perhaps as many as 50,000 Europeans, including nearly 15,000 in France.

This week’s North American heat wave cannot be definitively linked to climate change. (Nor can any other weather event for that matter.) But hotter-than-normal weather is an instructive reminder that global warming is, you know, warming the planet. And that has real consequences for our health.