The incredible power of Hurricane Ida was on display Sunday as the storm reversed course of the mighty Mississippi.
The river temporarily flowed from south to north on Sunday afternoon after Ida made landfall as a Category 4 storm that has experienced rapid intensification. US Geological Survey data shows that a river gauge at Belle Chasse, just southeast of New Orleans, recorded the astonishing about-face of the Mississippi River.
The Mississippi was discharging about 350,000 cubic feet (9,910 cubic meters) of water per second in the days before Ida’s arrival. Water moved upstream at a rate of 40,000 cubic feet (1,132 cubic meters) per second. That’s a staggering amount of water to return. Ida is expected to push 5 meters (16 feet) of storm surge inland, with the highest flooding covering an area from the Port Fourchon petrochemical center to the mouth of the Mississippi. The turning of the river is indicative of the power of this surge.
This is a phenomenon that we have seen with other storms, especially hurricane Florence in 2018. This has contributed to what is called compound flooding where the storm surge pushes water inland where the rain falls. With the water growing on land, the rain has nowhere to run.
With Ida, this might become a bigger concern as day turns into evening and the storm lingers. The National Hurricane Center noted in its most recent discussion of the forecast that “Ida’s forward movement has slowed.” Slower movement means bands of rain can repeatedly sweep over a given location, resulting in higher precipitation totals and more flooding.
Although she spent hours on earth, Ida also failed to weaken significantly. The storm also continues to blow winds of 130 mph (209 km / h), in part due to what is known as the brown ocean effect, which occurs when storms are able to suck l moisture of the earth itself and maintain their strength even as they move. interior. (The effect even helped support a tropical cyclone to the Great Lakes, although in a much weaker state than Ida.)
In the case of Southeast Louisiana, “land” might be a generous statement; the region is mainly made up of bayous and barrier islands which have become even more fragmented and aquatic thanks to the fossil fuel industry causing subsidence (in addition to the rise in sea level caused by the combustion of said oil and gas). The dike system and containment of the Mississippi River have leads to another shipwreck in what scientists have said, this is the worst case scenario for the state.
There are many reasons to be concerned about this in the long run. But what that means now is there’s plenty of warm, shallow water to refuel Ida as she crawls north. And while the Mississippi hasn’t changed course since, the storm still has a lot of damage to its system.