Columns

By mid-morning on August 12, more than a foot of rain had fallen near Kentwood, Louisiana, in just a 12-hour stretch — a downpour with an estimated likelihood of just once every 500 years, and roughly three months’ worth of rainfall during a typical hurricane season. It’s the latest in a string of exceptionally rare rainstorms that are stretching the definition of “extreme” weather. It’s exactly the sort of rainstorm that’s occurring more frequently as the planet warms.  

The rain fell for days, sometimes 3 inches or more in a single hour, as streets became rivers and rivers ate up entire neighborhoods in southeast Louisiana. Between Aug. 11 and Aug. 14, more than 20 inches of rain fell in and around East Baton Rouge, one of the hardest-hit parishes. And in some parishes in the region, as much as 2 feet of rain fell in 48 hours. Just west of Baton Rouge the town of Livingston, for example, received a total of 25.5 inches in the four days, according to weather service data. That would mean for the town with just over three square miles, over one billion gallons of water fell. 

While it is a little like comparing apples and oranges, San Francisco's annual rainfall for all of 2015 was 23.26 inches. 

After the floods recede, residents may have no choice but to leave. Thirteen people died in the flooding and more than 60,000 homes are estimated to be damaged by flooding and many are not insured. The Federal Emergency Management Agency (FEMA) has already paid out $127 million in assistance and more than 116,000 have registered with FEMA for support, including temporary shelter, rental assistance and emergency repairs. 

Louisiana already has the fourth highest unemployment rate in the U.S. at 6.3%; it has lost 2,000 oil and gas drilling jobs in the last two years. If Louisiana loses population, this will mean loss of money spent on businesses and taxes. For example, the population of Louisiana slipped 6% in the year after hurricanes Katrina and Rita hit the area in 2005, and it took more than five years for the population to come back to pre-storm levels. 

Rick Ramsey, mayor of Walker, Louisiana -- about 20 miles from Baton Rouge -- has threatened to sue the State of Louisiana and the federal government, saying they were the cause of the flooding. He blames the construction of Interstate 12 for the rising waters. Ramsey said he warned officials about the chance of flooding because of the road's construction. About 80 percent of homes were flooded in the area. Ramsey expects many insurance companies will want to join the potential lawsuit because they now face having to pay billions of dollars in claims. 

Unless we take immediate action to reduce global warming, these impacts will continue to intensify, grow ever more costly and damaging, and increasingly affect the entire planet.