On the fifth anniversary of Hurricane Harvey a new study had assessed the impact climate change had on the severity of the storm.

The research found that if it were not for the impact of climate change, up to 50 percent of residences in Houston’s Harris County would not have been flooded by the hurricane. Harvey, a Category 4 hurricane made landfall in Texas and Louisiana in 2017, causing massive flooding in Houston.

“We already know that climate change is increasing the severity and frequency of extreme weather events,” said Kevin Smiley, the study’s lead author and LSU Department of Sociology assistant professor. “But now researchers are able to pinpoint the extent of damage from a specific extreme weather event such as Hurricane Harvey and the resulting floods.”

Fifty percent less residences impacted equates to about 50,000 fewer homes damaged and billions of dollars saved in residential damage, added the study.

“This means that we have quantified the contribution of climate change to the suffering of people who live there,” said Michael Wehner, the study’s co-author and senior scientist at Lawrence Berkeley National Laboratory.

The research, a first of its kind investigation into potential disparities between those impacted by the climate change-induced flooding, also found patterns of racial and economic disparities.

“Part of the reason why low-income neighbourhoods flooded has to do with the historical development of Houston along its waterways and surrounding petrochemical corridor,” Smiley said. “There’s a clear climate and environmental justice story as to where these neighbourhoods are located.”

Climate change attribution, which ascertains the connection between climate change and extreme weather events, involves running computational models to estimate how much these changes in climate make extreme weather events, like hurricanes, more severe. Scientists can compare these estimates without climate change to what actually happened to see the difference.

“This is the first end-to-end impact attribution study of a specific weather event following on our previous studies showing a significant increase in Harvey’s precipitation and the resulting flooding increase because of climate change,” Wehner said.

The authors said while discussions tend to centre around climate change forecasts for the future, the study underscores the fact that climate change is impacting life now.

“Climate change is happening right now with real and substantial costs,” Smiley said. “Three to five extra inches of rainfall from climate change can make the difference between your lawn getting soaked and your house getting flooded leaving it uninhabitable.”