*it's about to get hairy in New Orleans. Again, and then again and again. The Mississippi River has been flooding literally all year.
You were warned, just not by climate denialists
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The storm’s timing is unique: In 168 years of hurricane records, a July hurricane in Louisiana has only happened three times, and all of those occurrences have been within the past 40 years. There’s a growing body of research that shows that as the Gulf of Mexico waters warm because of climate change, early-season hurricanes like proto-Barry could become more common. (Right now, water temperatures in the Gulf are at near-record levels, more typical of peak hurricane season.)
More concerning than the storm’s early timing, however, is its bad timing. The Mississippi River has been continuously flooding southern Louisiana since January 6, the longest flood in recorded history for the river in this region. Spring floods aren’t supposed to last until mid-July, and after 185 days of high water, it’s unclear Louisiana could handle any more. A potential worst-case scenario could prove disastrous for Louisiana, and shows how unprepared we are for the scary new era of overlapping climate disasters.
In Louisiana, there are two types of levees: those that protect the coast from an ocean storm surge, and those that are designed to keep the Mississippi River in its current course. Katrina caused a failure of the storm surge levees. This week, the river levees—which were first built after the historic 1927 flood—are being put to the test for the first time in modern history.
As much as 15 to 20 inches of additional rain is possible this weekend as the storm moves inland, according to the latest weather models. And because Barry’s storm surge could essentially block the flow of the river from reaching the Gulf of Mexico, the National Weather Service now forecasts that the Mississippi may rise to 20 feet—the highest crest since 1927, before the modern levee and spillway protection system was completed. In New Orleans, the river levees are only 20 feet high in some places....
