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Despite record rainfall and catastrophic flooding in 2016, EBR planners encourage development on recently flooded landscape

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by Len Bahr, Ph.D.

On New Year’s Day the advocate.com published an article by Grace Toohey on Louisiana’s record-smashing 90.54 inch cumulative rainfall in 2016, despite an unprecedented drought throughout the month of October. In researching her article she interviewed state climatologist Barry Keim and National Weather Service meteorologist Alek Krautmann, both of whom blamed the precipitation record on the 2016 El Nino phenomenon but would not relate it to climate change. “I think I would attribute it to dumb luck,” Keim said, adding, without a trace of irony, that “Weather is just unpredictable.”

Blaming the rainfall record on El Nino rather than climate change is a distinction without a difference.

For example, consider this peer reviewed 2014 report in natureclimatechange.com by 14 co-authors that links the increasing frequency of severe El Nino Pacific Ocean warming occurrences since 1982 to global greenhouse warming.

Here’s the abstract of the paper, which was published two years before the 2016 season:

El Niño events are a prominent feature of climate variability with global climatic impacts. The 1997/98 episode, often referred to as ‘the climate event of the twentieth century’ and the 1982/83 extreme El Niño, featured a pronounced eastward extension of the west Pacific warm pool and development of atmospheric convection, and hence a huge rainfall increase, in the usually cold and dry equatorial eastern Pacific. Such a massive reorganization of atmospheric convection, which we define as an extreme El Niño, severely disrupted global weather patterns, affecting ecosystems, agriculture6, tropical cyclones, drought, bushfires, floods and other extreme weather events worldwide. Potential future changes in such extreme El Niño occurrences could have profound socio-economic consequences. Here we present climate modelling evidence for a doubling in the occurrences in the future in response to greenhouse warming. We estimate the change by aggregating results from climate models in the Coupled Model Intercomparison Project phases 3 and 5 multi-model databases, and a perturbed physics ensemble. The increased frequency arises from a projected surface warming over the eastern equatorial Pacific that occurs faster than in the surrounding ocean waters, facilitating more occurrences of atmospheric convection in the eastern equatorial region.

Now consider the record strength of El Nino during December 2015 through February 2016, as described in this NOAA bulletin:

This year’s El Niño, among the strongest on record, is expected to influence weather and climate patterns this winter (2015-16) by impacting the position of the Pacific jet stream.

On December 19, three weeks prior to Toohey’s report, the advocate.com published an article by Andrea Gallo on the unanimous approval by the East Baton Rouge planning commission of a new residential housing development on the NW side of Burbank Drive, despite the fact that the Baton Rouge Deluge of 2016 had flooded the landscape in question.

Here are some telling quotes from exchanges during the meeting:

David Lindenfeld, speaking on behalf of Together Baton Rouge, also asked the planning commission to be mindful of the possibility of climate change in their planning regulations. He said the commission should not ignore warming temperatures in Baton Rouge, nor should it ignore rising sea-levels that would affect drainage in local waterways.

Duke reminded the commissioners that the Metro Council instructed them not to consider the August flood in future stormwater calculations because the council deemed the flood a unique event.

Would anyone like to hazard (pun intended) a guess as to whether the houses to be constructed in this, Louisiana’s latest example of planning gone awry, will be elevated on piers or constructed slab-0n-grade?

So there you have it, Louisiana’s record rainfall in 2016 could have been an extremely rare statistical anomaly, casually dismissed with the colorful phrase ‘dumb luck’ and so unlikely to reoccur as to not justify consideration in terms of future residential flood risk. On the other hand the cumulative rainfall could have represented a series of extreme weather events in 2016, probably linked to the severe El Nino occurrence that was in turn linked to global warming.

This is a distinction with a huge difference.

 

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  1. Anonymous says:

    If your plans for the future depend on a significantly smaller carbon-based economy, then think anew. If your plans are based on La getting any fraction of $92B, then think anew. If your plans are based on these diversions building Land,” much less achieving the claimed reduction in storm surge, then think anew.

    http://thelensnola.org/2017/01/03/latest-coastal-restoration-plan-says-thousands-of-homes-may-have-to-be-elevated-or-bought-out/

    http://coastal.la.gov/wp-content/uploads/2016/08/DRAFT-2017-Coastal-Master-Plan-ilovepdf-compressed.pdf

  2. stormineaux says:

    The false notion that that climate change is a hoax or even a conspiracy among scientists to obtain grant funding, is popular in Louisiana, especially with elected officials. Therefore, bringing the subject of climate change into a discussion of flood control measures serves to divert attention away from what can practically be done to reduce flooding and towards the idea that nothing can or should be done. From my six decades of personal experience, massive rainfall events appear to be common occurrences in the South Louisiana/coastal East Texas region, and the “unusual” aspect of the August floods was not the magnitude of the rainfall, but that the rainfall occurred in the Baton Rouge area rather than in New Orleans, Lake Charles, or Houston. Climate change or not, a local deluge will probably happen again, and the local government should do what it can to protect existing developments from water displaced/diverted by new developments.

  3. Anonymous says:

    No one could possibly be blind enough to not grasp how large a burr under your saddle climate change is. Nonetheless, permit me to observe that there’s no point in failing to appreciate larger events when the current system used to plan and build cannot handle normal events.

    It takes some digging, but the “WINN 2016” (formerly known as “WRDA”) bill discussed in this New Orleans Advocate story, “Long-awaited $744 million hurricane levee for River Parishes authorized in bill signed by Obama [;] Assembling the money is another story,” includes priority status for this project, “Amite River and Tributaries, Louisiana, East Baton Rouge Parish Watershed,” signed chief’s report, 23 Dec 1996.

    That 1996 report recommends a lot of work in and near the subdivision just approved. It features in para 2 “channel modifications, for the purpose of reducing flood damages, to five separable elements which are independent watersheds within the parish of East Baton Rouge. These watersheds are Blackwater Bayou and its main tributary, Beaver Bayou, Jones Creek and tributaries, Ward Creek and tributaries, and Bayou Fountain. The total plan for all five watersheds consists of modifying approximately 66 miles of channel. This includes approximately 25 miles of minimal channel clearing and snagging, 24 miles of earthen channel enlargement, and 17 miles of channel concrete lining. Fish and wildlife mitigation features consist of the reforestation of 397 acres of cleared land to compensate for an estimated 280 acres of bottomland hardwoods that would be lost to project construction. The project includes one recreation feature, an 11-mile bicycle path in the Jones Creek watershed, to be constructed on land required for the flood damage reduction purpose.”

    Meanwhile “y” of para 8 goes on to add “Publicize floodplain information in the area concerned and provide this information to zoning and other regulatory agencies for their use in preventing unwise future development in the floodplain, and in adopting such regulations as may be necessary to prevent unwise future development and to ensure compatibility with protection levels provided by the project;”.

    Notice that the 1996 EBR project just gets a lot more water sooner to Bayou Manchac, and thus to the Amite. Where that water goes next and how the Manchac/Amite combo are supposed to get it there is NOT part of the project. This 1996 work just gets it to the SE corner of EBR much faster. After that?

    QED, I’m really having trouble seeing why we should care about large events when we do a spectacularly bad job of handling “normal” ones.

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