Torrential rain storms can flood homes, wash out roads and bridges, and destroy crops. Over the past three decades, flooding from heavy precipitation has caused about $200 billion of damage in the U.S.

Frances Davenport is a PhD student in Earth system science at Stanford University. She wanted to know how much of that enormous price tag can be blamed on global warming.

“We’ve seen that extreme precipitation events are increasing in frequency or intensity, and so we wanted to quantify what are the financial costs of those changes in precipitation,” Davenport says.

Her team analyzed historic rainfall trends and financial data about flood damages over decades. 

They estimated that between 1988 and 2017, about $73 billion of flood damage can be attributed to increases in extreme precipitation. That’s more than a third of the cost of flooding over those 30 years.

So Davenport says that people are already paying the financial costs of a warming world.

“I think having those hard dollar amounts is really important for some of these policy conversations about what to do,” she says.

Reporting credit: Sarah Kennedy/ChavoBart Digital Media