If Mother Nature has her harsh way, we’ll be rebuilding marsh for a long, long time in coastal Louisiana.

That is a given, however challenging our state’s goals for dealing with the unprecedented impact of both subsidence and rising sea levels.

The 2012 master plan for the coast boldly sought to halt the wetlands loss that sees an average of a football field eroding away from the coast every hour. But like all long-range plans, that ambition was based on assumptions, including a moderate level of sea-level rise.

Now, the master plan is being revised, but even as it is, there are increasingly disturbing numbers from international scientists about the impact of global warming on the seas.

“We don’t believe that anymore,” said Johnny Bradberry about the master plan’s ambitions of no net loss of land in the state. He is the new executive assistant to the governor for coastal activities and chairman of the state’s coastal authority.

Karim Balhadjali, deputy chief at the state Coastal Protection and Restoration Authority, explained that the “no net loss” projection depended on forecasts that predicted only moderate levels of sea rise.

The officials are right to face forthrightly the difficulties of repairing the vast impact of erosion and subsidence on the coast.

David Muth, director of the National Wildlife Federation’s Gulf Restoration Program, noted that the less optimistic scenarios in the master plan didn’t promise a net gain in coastal land.

“Obviously, it’s become clearer five years since the master plan that the projected sea level rise has become worse,” Muth said. “It really comes as no surprise.”

Is coastal restoration a myth? Hardly. In fact, the state’s coastal authority and its collaborating federal, university and private-sector partners deserve credit for a great deal of increase in acreage in the coastal zone. But it’s a major task to get ahead of the impact of rising seas around the world.

The original $50 billion price tag over 50 years also is likely to increase with the new 2017 master plan, Bradberry said, in part reflecting changing conditions along the coast like the more dire forecasts for sea-level rise.

Preserving the marshes is critical, for they provide important defenses against hurricanes, absorbing surge and reducing flooding. That saves lives and property; even one major storm can cause billions of damage if the coastal buffer is denuded over decades.

Col. James Waskom, the head of the state emergency preparedness agency, emphasized the word “resiliency” in his talk Monday to the Press Club of Baton Rouge. That is a big goal for the work of the Federal Emergency Management Agency and its state partners, Waskom said.

It’s also one of the key goals for Mayor Mitch Landrieu and the city of New Orleans’ plans to become better prepared for future events.

The state and its partners are increasingly focusing on what are called “nonstructural” projects, which might not directly involve levees or floodwalls.

Jacques Hebert, spokesman for the Restore the Mississippi River Delta Coalition, said a lot of work still can be done to prevent the worst-case scenario of continued erosion that leads the Gulf of Mexico up to the doorstep of cities like New Orleans, Houma and Morgan City.

“Our perspective is it’s not a time to slow down the master plan; it’s time to accelerate it,” Hebert said. “It will do a lot of good in protecting a lot of communities across the coast and industry and wildlife.”

We agree with that agenda. And we believe that it is important that the state’s coastal authority and other agencies lay out the hard facts on their tasks.