Hurricane Harvey on Aug. 24, 2017. (Photo courtesy of NASA)

Hurricane Harvey was historic: it literally set the rain record for the United States with a whopping 51.89 inches of rain in Harris County, and covered most of Houston, the country’s fourth-largest city, in floodwaters that caused hundreds of billions of dollars in damage.

The “exceptional” rains were intensified by 15 percent due to climate change, according to a new study in the journal Environmental Research Letters. Climate change also made Harvey three times more likely in the 21st century, as opposed to conditions of about a century ago.

“As the world gets warmer, as the globe gets hotter, the likelihood of these storms… is increasing, especially along the Gulf Coast region,” said Antonia Sebastian, a Rice University postdoctoral researcher who collaborated with scientists from the Netherlands on the paper. “The takeaway from this paper is, Harvey is more intense, and is more likely in today’s climate.”

The study looked at weather records from the late 1800s, and compared them to the current conditions in 2017 that made Harvey “tick.”

The three computer models were based off atmospheric conditions, and the corresponding precipitation amounts, spanning from the mid-19th century to the present. One of the models also extends into the future.

The analysis concluded that Harvey was exceedingly rare: it is a 1-in-9,000-year event, the researchers found.

“This analysis makes clear that extreme rainfall events along the Gulf Coast are on the rise,” they conclude.

The paper did not tackle other factors in the massive flooding, including sea level rise, land use changes in the greater Houston area, and storm surge effects along the coast, they added.

The work of Sebastian, the Royal Netherlands Meteorological Institute, the Red Cross Red Crescent Climate Centre in The Hague, Oxford University, and Princeton University is part of the World Weather Attribution collaborative group. The study was supported by the MacArthur Foundation.