Climate change softens up already-vulnerable Louisiana

Dan Vergano | USA TODAY

Show Caption Hide Caption Weathering the Change: Hurricanes As part of USA TODAY's Weathering the Change series, we look at how climate change could affect hurricanes.

Louisiana%27s sinking coast faces the threat of stronger hurricanes due to climate change

Efforts are underway to reverse man-made subsidence and rising sea levels to protect the coast

Some worry a 50-year%2C %2450 billion plan to restore wetlands is too little%2C too late

GRAND ISLE, La. — Pelicans and pickups roam the beach, where the waves roll in and return, lapping over the open water of the Gulf of Mexico.

The water covers land that was once beach, and it has devoured land that was once marsh tucked behind this 6-square-mile barrier island, a speed bump for hurricanes headed north from the Gulf.

On this sunny day, the Tarpon Rodeo — billed as "the oldest fishing tournament in the United States!" — is underway, with fishing boats and truck-bed hot tubs competing in nearly equal numbers on the road . But beneath the sunshine here on the edge of this vanishing wetland, human mistakes are adding up.

Indeed, the in-your-face transformation — a product of climate change and the rewiring of the Mississippi — is threatening the spawning grounds for much of the nation's seafood, the pit stop for the Gulf's oil industry and the home of the beloved bayous and fishing "camps" that make life here unlike anywhere else. With every bit of wetlands lost — each day a football field's worth — the people and places of the Gulf Coast become that much more vulnerable to the next hurricane.

"I revel in every moment I'm out on the beaches, the bayous, the ponds," says Al Duvernay, 61, a life-long Louisianan. A retired oil industry worker, Duvernay now volunteers for efforts to rebuild the land sinking under the waves, a retreat he has seen firsthand over the course of a lifetime spent on the Mississippi River Delta. "Another part of me is compelled to come back here, because I know it is all going away."

In the past eight decades, Louisiana has lost 1,880 square miles of coastal marshes, or an area about the size of Manhattan every year. With another hurricane season upon us, it is land that Louisiana and the nation can ill afford to lose. The same threat of lost barrier islands and wetlands stalks more than half of the coastal properties of the continental United States, extending from Maine to Texas. But here in southeastern Louisiana, it's at its worst.

USA TODAY traveled to this place where the Mississippi meets the Gulf of Mexico as the sixth stop in a year-long series to explore places where climate change is changing lives.

"The sea is rising and the land is sinking," says Louisiana state climatologist Barry Keim of Louisiana State University in Baton Rouge. "The two together mean that wetlands are disappearing here at unprecedented rates worldwide." Add in the threat of more powerful hurricanes spurred by climate change, Keim says, "and you have to worry about the past repeating itself here."

"Louisiana is in many ways, one of the best examples of starting to see some of the near-term implications of climate change," says environmental policy expert Jordan Fischbach, of the Pardee RAND Graduate School in Pittsburgh, part of the team that last year developed tools for the state to decide what coastal restoration projects to pursue. "In some ways, I feel like it is the canary in the coal mine because they are seeing effects that change people's day-to-day lives."

Cemeteries are sinking and washing away in towns like Leeville, La., on their way to becoming isolated spits of land. Onetime orange groves and cotton fields are now covered with water.

Change here is constant but not subtle, so authorities have embarked on ambitious projects to, actually and figuratively, turn the tide. In May, the Louisiana Coastal Protection and Restoration Authority (CPRA) announced 39 projects it hoped to see reverse the damage, part of a 50-year, $50 billion plan. They range from restoring marshes to spilling fresh river water into the delta to rebuilding barrier islands.

Every 3 miles of wetlands restored means 1 foot less of hurricane storm surge, the water wall pushed ahead of storm winds that is often one of the biggest killers in a hurricane, Keim says.

"I worry a 50-year plan isn't enough, that it won't be enough," Keim says. "If we were talking about a 500-year plan, or a 1,000-year plan, that might be enough to bring things back."

The storm surge in Hurricane Katrina reached a record 25 to 28 feet, where it hit hardest in Mississippi. It killed 1,200 people and caused $75 billion in damages, according to the National Oceanic and Atmospheric Administration.

"Once you go through something like Katrina, you are never the same," says Duvernay, who spent the day after the storm in his fishing boat rescuing his neighbors, people trapped in the upper floors of their drowned homes. "You never want to see that again."

MISSISSIPPI MISTAKE

Driving along Louisiana State Highway 1, more a bridge than a road from New Orleans to Grand Isle, Hilary Collis of the Coalition to Restore Coastal Louisiana looks across wide-open lakes and estuaries, a few slivers of sand and mud dotted with marsh grass and short, squat mangrove trees. She then points to what isn't there anymore.

"All the open water you are seeing was once wetlands," Collis says. "Just a few millimeters at a time it sank, and now it's gone." Unlike the vanished cypress trees that once dotted the marsh lining the bayou that parallels the highway, the mangroves have migrated from farther south, thriving in today's brackish water and warmer temperatures.

How did it happen? For one thing, the Mississippi River has stopped doing its job: building wetlands. A massive levee program beginning in 1927 rerouted the Mississippi and put it "in a straitjacket," Keim says, kept its freshwater and mud from spreading across the Mississippi River Delta and replenishing the marshes. So without the silt, the marshes started to sink.

"They turned off the sand and mud machine that built up the wetlands," is how Duvernay puts it.

At the same time, the sea has risen about 7 inches globally in the past century, driven by climate change, alongside an increase of Earth's average surface temperature of more than 1.4 degrees. The increase is largely due to heat-trapping carbon dioxide and other greenhouse gases, emitted into the air by burning coal, oil and other fossil fuels, boosting temperatures, according to the U.S. National Academy of Sciences. On the world's coasts, the result has been a change from the past 1,900 years of stability, as a warmer ocean expands and warmer air melts glaciers, leading to higher seas.

Along Louisiana Highway 1, which carries travelers the last 60 miles from Lockport, La., to Grand Isle, the results are clear. Dead cypress trees killed by saltwater still stand in isolated spots, ringing ponds that have become brackish lakes.

"I watched it all happen, places where I could fish and camp as a child are now just open water," Duvernay says.

Keim, also a Louisiana native, sheepishly admits that he grew up as a child thinking that cypress trees just looked that way, dead. "It took a little education to figure out that the intrusion of saltwater had killed them all in the years before I was born," he says.

Louisiana 1 is also the only road to Port Fourchon, the southernmost port in Louisiana, which supports 90% of the nation's offshore oil and gas rigs. Vulnerable to flooding, the highway is the key to 18% of the nation's oil production, according to January's draft of the federal National Climate Assessment report. "Every time there is a high tide or any storm, that road goes out," Fischbach says.

And one final problem: Four major hurricanes — Katrina (2005), Rita (2005), Gustav (2008) and Ike (2011) — have battered the region since 2005. Eroded, inundated, cut up by oil company canals and even gnawed to the roots by invasive South American rodents called nutria ("They eat marshland in its entirety," Keim says), the wetlands' ability to halt these goliaths' storm surges has been undermined.

The same warming ocean waters that are slowly rising also look likely to deliver more powerful hurricanes to these shores. A 2010 Nature Geosciences study led by Thomas Knutson of NOAA's Geophysical Fluid Dynamics Laboratory in Princeton, N.J., concluded that future storms would be as much as 11% more intense in this century, dropping about 20% more rain within 60 miles of their center.

On the plus side, global warming might mean that fewer storms form — as many as 34% fewer — in the years ahead. So we might see fewer, meaner storms, across the planet. Though the frequency question is one of the many unsettled areas of climate science, as some experts such as MIT's Kerry Emanuel predict a proliferation of storms with these warmer conditions.

The debate matters not, Keim says.

"We don't need to know the answer to look at the data and know that hurricanes have hit the Gulf Coast hard in the past," Keim says. "And the numbers tell us that where something has happened in the past, it will happen again."

WHAT CAN BE DONE?

Once a stomping ground of the pirate Jean Lafitte, Isle Grand Terre is a patch of sandy scrub curving before the Gulf of Mexico next to Grand Isle, a barrier island that shelters salty lagoons, marshes and bayous from the open sea. The island is home to five abandoned scientific buildings, the ruins of a Confederate fortress and mosquitoes that swarm visitors in packs. It is also the home of a dune rebuilding project sponsored by the local beer company, Abita, that Al Duvernay volunteered for earlier this year. He and other helpers were brought in by barge in shifts to plant the dunes.

"This is success," says Collis, pointing to a strip of dune grass stalks that extends several hundred yards along a newly installed beach fence, set about 40 yards back from the surf. Sand has already started to pile up against the fence, burying slats 2 inches deep, the start of a new dune guarding the beach. Volunteers had planted 18,000 stalks in the sand over two days in March, and now they stood erect, their roots bidding to become another bulwark against a future storm.

"The idea is the dune and the dune grasses grow together, becoming larger and larger," Collis says. "If someday a hurricane comes and digs it all up then at least it will have done its job of taking some energy out of the storm."

Even so, volunteer projects — planting grasses on dunes, or mangroves in lagoons — go only so far. The state coastal authority's industrial-scale projects are now beginning after more than two decades of planning, arguing and voting. They received overwhelming support last year from the state Legislature. Interestingly, the state's plan doesn't mention climate change; it just assumes it will happen. The estimated rise in sea levels form the backdrop against which projects are picked for priority.

At Port Fourchon, just a few miles down from Grand Isle on the oft-flooded Louisiana 1, for example, a $5.4 million "Geotube" project now underway is stuffing 6-feet-wide fabric tubes with sand nearly a mile down the beach.

But not everything is proceeding seamlessly. The fight over the coastal restoration plan has inevitably headed to the courts. Some oyster farmers are suing the state's coastal restoration project for Mississippi freshwater diversions that could harm oyster beds. The goal of the diversion is to restore delta-building sediment to sinking parts of the region and counter the saltwater creeping ever farther inland.

The state's levee authority last month sued oil and gas companies for decades of cutting canals willy-nilly through wetlands and letting saltwater in from the Gulf. Louisiana Gov. Bobby Jindal, a Republican, is disputing the levee authority's right to file the lawsuit.

CROWDING THE COASTS

Yet the legal issues often fold into the environmental ones, and those concerns lead to another place of concern along the U.S. coastlines: overdevelopment. About 39% of the U.S. population (works out to about 123 million people) now live in shoreline counties, according to Census data. The deluxe camps on Grand Isle — seemingly almost daring the next hurricane's wrath — are just one symptom of this rush to the coast

"Global warming doesn't make people buy beachfront condos," Keim says, pointing to another piece of the hurricane dilemma.

A quiet period for hurricanes that ended in the 1990s lured the nation toward beach living, sparking a coastal construction boom that is still underway. From Louisiana's camps and vacation homes perched high on stilt-like piers, to New Jersey's shore towns, Americans still can't get enough of warm waves and soft sand and are often undaunted by the dangers building on our coasts.

Those who are taking up this fight, though, see a silver lining in these dark clouds.

"I am happier than I have been in a long time that some places will be saved," Duvernay says.

He cites not his own volunteer efforts, or his fishing habit, but the realization that officials are starting to pay attention to this changing world.

"I'm happier there is a plan with some funding," Duvernay says, "but I still worry it might be too little, too late."

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