Imperceptibly to most, the moon’s orbit is pushing
1.6 inches away from the Earth each year.
So, too, is sea level rising imperceptibly to many, but it’s expected to pose a real threat at the doorstep of the next generation, their children and their grandchildren.
The National Oceanic and Atmospheric Administration has reported sea levels are rising along parts of the Florida coast by more than a third of an inch annually. The sea level rise is coupled with the recent annual jump in global temperatures.
Predictions suggest “global (sea level rise) of approximately 20 (7.8 inches) to 60 cm (almost 2 feet) during the 21st century if polar ice sheets remain stable but possibly more than 1 meter (39.4 inches) if ice sheets become unstable,” the Florida Department of Economic Opportunity stated in a 2011 report.
Specifically, if present patterns persist, in 2025, Charlotte Harbor could rise a minimum of 1.8 inches and a maximum of nearly a foot, and by the end of the century, Charlotte Harbor sea levels could rise to 7.1 inches or the rise could approach 4 feet, the DEO stated.
Locally, sea level is rising annually about 3 millimeters, or one-tenth of an inch, said James Beever, a planner with the Southwest Florida Regional Planning Council.
That doesn’t sound like much, but Beever suggests people think of sea level rise as stacking cheese slices one atop another and another and another well-into the future.
In 25 years, Beever said, he wouldn’t be surprised if local sea levels rose 2.5 inches or more. That’s another 2.5 inches of water lapping against shorelines during high tides or battering the coast with storm surges.
With sea level rise, developments with man-made finger canals could see more water pushing inland.
“Sea level rise never rests,” Beever said. “Miami is a lot of worse than we are. We have natural shorelines, but that’s not going to be enough in the end.”
When it comes to climate change, Beever said, belief in whether it is real or not is optional. However, dealing with it is mandatory.
Some communities remain blind to sea level rise, allowing dense urban development right up against shorelines. Those developments could find themselves wading in the Gulf or other water bodies in a decade or two.
Both Sarasota and Charlotte counties address sea rise in their comprehensive plans.
“In the 2016 update to the Sarasota County Comprehensive Plan, a policy was added to address sea level rise, encouraging planning, sharing information, and collaborating with others in the region,” Sarasota County sustainability director Lee Hayes Byron said. “Sarasota County is currently working on an internal assessment of its own facilities and infrastructure to determine what may be vulnerable to future sea level rise.”
The city of Sarasota organized an informal group of local government staff — including North Port, Sarasota County, Venice and Longboat Key — to discuss sea level rise planning. That group has met occasionally over the last two years to share information on efforts to assess vulnerabilities and consider planning strategies addressing sea level rise, Byron said.
A similar regional effort is underway. Science and Environment Council of Southwest Florida has recently established the Climate Council of Sarasota-Manatee, which is “a facilitated network of experts and practitioners working on climate change issues in the Sarasota-Manatee Region.” More about the climate council and its initiatives can be found at www.scienceand environment.org.
Charlotte County has also identified sea level rise in the natural resources chapter of its comprehensive plan. No specific policies are outlined, except that future levels of service will take into account impacts from sea level rise.
“The coastal high hazard elements of the comp plan are all factored into land development regulations,” county spokesman Brian Gleason said when asked how are comp plan policies implemented.
“The flood maps are continuously updated to reflect changing models and federal flood insurance coverage,” Gleason said. “And elevation requirements are in place and undergo reviews as part of the Florida Building Code updates.”
The city of Punta Gorda is often cited as a Florida jurisdiction that is meeting the challenge of sea level rise head on. In 2015, Punta Gorda received recognition from the Southwest Sea Level Rise Summit.
Beever, along with his wife, Lisa — who was then the executive director of the Charlotte Harbor National Estuary Program — assisted with city officials on a sea rise adaptation plan that garnered support from Punta Gorda residents.
“We promote good planning,” city chief planner Joan LeBleau said. “Does Punta Gorda know whether sea level will rise? No. But we plan on it potentially coming.”
The city has taken incremental actions, such as modifying its development codes, and has undertaken downtown and other stormwater projects. The projects benefit “all of us,” LeBleau said.
The city also created an oyster bar in waters off its Harbor Walk along the east side of the city. LeBleau explained how oyster bars can diffuse the energy of waves approaching shorelines.
Working with the Nature Conservancy, Punta Gorda is investigating whether a similar oysters bar or planting mangroves could benefit and protect its downtown business district fronting on Charlotte Harbor. These can serve as living shorelines, natural barriers that help control flooding, erosion and improve the local ecology, according to the National Estuary Program.
Sea level rise, however, is only symptom of greater changes in the near future.
Sea levels and climate
Sea level rise is coupled with the annual rise of global temperatures.
“Accelerating sea level rise has become the poster child of climate change, and it will be quite impactful,” said William Butler, Florida State University urban planning professor. “Indeed, Florida is likely to be the most impacted state in the U.S. within this century, given our low-lying topography and high population concentrations on the coast.”
Other implications of climate change and effects in Florida, Butler suggested, could be equally worrisome and severe. For example, the current red tide crisis and wildfires.
“(Brush fire) season is already longer than it used to be and continues to lengthen and worsen,” he said.
Hurricane season could last longer and storms may get more powerful. The near future could see a greater frequency of 25-year storms or 100-year storms.
The impact of Hurricane Maria on Puerto Rico may be a harbinger of what’s to come to Florida — not to mention its aftermaths. The hurricane led to an exodus of Puerto Ricans from their island homes, many of whom have since resettled in Florida including Charlotte and Sarasota counties.
“A lot of the trends are inconclusive — we just don’t have the long-term data needed to make the call,” Butler conceded. “But there is generally strong agreement that our weather-based hazards are going to be less predictable in the future.”
“Climate change is now, not in the future,” Beever said, citing how Louisiana, the Texas Gulf coast, and Newport, Virginia, as areas already wrestling with sea level rise and climate change.
Like Butler, Beever also expects Florida to see longer dry seasons, coupled with shorter but wetter rainy seasons. Tropical diseases, including those carried by mosquitoes, will infest more northern climes. More changes in the flora and fauna should also be expected. It’s already being seen, Beever said, citing how pythons and iguanas have become well-established in Florida.
Beever could imagine future Floridians being more susceptible to heat stroke from hotter days and spending more money for air conditioning and irrigation. Coastal residents may experience shorter intervals between beach nourishment projects, he said.
It could be worse.
Continued global warming might be expected to dry out Florida into a desert — if the state wasn’t a peninsula, surrounded by the Atlantic, Gulf and the Caribbean waters, Beever suggested. He noted how Florida is located on the same latitudes as the Sahara and other major deserts globally.