Sea level rise is a problem for Florida
Like a prophet of doom, Poseidon with computer models, the University of Miami’s Harold Wanless came to Naples to give us the latest scoop on ocean rise.
And his news wasn’t good: The sea is rising and we can’t stop it
Not by buying an electric car. Or shutting down the petroleum industry. Or covering the country with solar farms or the seashore with windmills. Wanless said if we stopped burning fossil fuels tomorrow, greenhouse gases already in the atmosphere would keep warming the planet for another 30 years.
“Ice melt and sea-level rise will continue for centuries,” he said.
Wanless pointed out that 93 percent of warming is transferred into the oceans, a 50 percent increase since 1997. The warming oceans, in addition to expanding their volume, are speeding the melt of Greenland and West Antarctica ice sheets — all contributing to rising seas. And it’s irreversible.
Wanless said, “There’s no way to turn it around. … It will take centuries before the atmosphere reaches equilibrium with the ocean.” Other scientists share his pessimism. A three-foot rise is already “baked in,” according to British researchers. Oceanographer John Miller said, “We are past the point of no return.”
Wanless’s gloomy message was essentially the same one he delivered to the Southwest Florida Sea Level Rise Summit at Florida Gulf Coast University in 2015, but with a twist. Things are worse now. The ocean is warming faster, the ice sheets are melting faster and the seas are rising faster. Melting glaciers now contribute as much as 30 percent to sea-level rise.
Initial NOAA projections had the ocean rising 0.5-2 feet by 2050 and 4-6.5 feet by 2100. The 2050 estimate is now 1.5-2 feet, and the 2100 projection has been boosted to 5-8 feet. Wanless said many scientists are predicting an 8.5-12.5-foot rise by 2100, with outliers as high as 30 feet.
Of course nobody knows. The models draw heavily on past data and trends. Rutgers’ Robert Kopp says, “There are reasonably good estimates for how quickly the seas will rise until 2050. Beyond that the models become deeply uncertain.”
What’s not uncertain is the potential for damage. Florida is the flattest state in the country, with 1,350 miles of shoreline and 76 percent of its residents living in coastal communities. An estimated $36 billion of property are at risk. A 4-foot ocean rise would swamp 20 percent of the coastal area. An 8-foot rise would put much of South Florida under water. Storm surges have already inundated parts of Miami.
But storm surges are temporary; the water eventually recedes. Actual sea-level rise is very gradual, almost imperceptible. In the Naples area, the sea has risen about 6 inches since 1970. Not enough to get anyone very excited. While serious planning is beginning on Florida’s east coast, not much is happening here.
But what is happening could be important. FGCU’s Mike Savarese and the University of Florida’s Peter Steng are mapping where the rising seas will go in Collier County, areas that are most vulnerable — a blueprint for what might be expected by 2030, 2050 and 2100. That should give local officials a starting point for planning.
What might they do?
- Tighten zoning for coastal areas
- Strengthen sand dunes and beach vegetation
- Add tidal lagoons, diversion canals, bioswales
- Elevate future roadways
- Upgrade drainage systems
- Move vital services inland
But don’t expect too much. Our officials have their hands full dealing with today’s problems, and there are plenty of them.
Sea-level rise, with all of its uncertainties, is tomorrow’s problem. It’s well down the priority list.
Dave Trecker is a chemist and retired Pfizer executive living in Naples.