New research found that the extreme rainfall that fell on Puerto Rico during Hurricane Maria is connected to climate change. Hurricane Maria produced more rain in Puerto Rico than any of the 129 storms to hit the island in the past 60 years. According to the study, a storm as intense as Maria is nearly five times more likely to form now than during the 1950s, due largely to the effects of human-induced warming. “What we found was that Maria’s magnitude of peak precipitation is much more likely in the climate of 2017 when it happened versus the beginning of the record in 1950,” said David Keellings, a geographer at the University of Alabama in Tuscaloosa and lead author of the study.

The study is the first to look in depth at the rainfall during Hurricane Maria. Extreme rainfall during both Maria and Hurricane Harvey—which struck Houston, Texas, a month prior—caused unprecedented flooding that placed them among the top three costliest hurricanes on record.