Over the next 200 years, if global warming predictions come true and nothing is done to prevent it, the ocean will surge into southwest Broward County. It will inundate Port Everglades and the million-dollar homes of Las Olas Isles. Fort Lauderdale's claim to be the Venice of America will become too true.
The South Florida Regional Planning Council on Monday released preliminary results of a study of the possible impact of rising sea levels on Broward, Miami-Dade and Monroe counties. The study is part of an attempt by the Environmental Protection Agency to help local governments learn what could happen if sea levels continue to rise and to make plans for dikes or other measures.
"The sea is rising, and we need to adapt," said James Titus, EPA project manager for sea-level rise.
The worst effects would not be on the beaches. Instead, the newly developed suburbs of southwest Broward County and western Miami-Dade County would suffer the most, as Florida Bay engulfed part of the Everglades and established a new Florida coast.
"Parts of Miramar, Pembroke Pines, Cooper City and Davie would have waterfront property on the bay," said John Hulsey, a senior planner who conducted the study.
The EPA estimates that global sea levels rose 6 to 12 inches over the past 100 years, with the rate of increase accelerating over the past decade. A growing scientific consensus blames global warming, the rise in atmospheric temperature causes by the emission of heat-trapping gases from automobiles, power plants and other sources. As water warms, it expands, raising sea levels. The higher temperatures also melt glaciers, a smaller but still significant cause of higher sea levels.
The South Florida study predicts the impact of a 5-foot rise in sea level over the next two centuries. It provides no interim estimates, so there were no projections of what would happen in 30 or 50 or 100 years.
As a low-lying coastal state, Florida would be particularly vulnerable. The most dramatic flooding would take place in southwest Broward and northwest Miami-Dade. As the water in Florida Bay rises, it would swamp the Shark River Slough, the broad saw grass plain that runs west of the developed sections of both counties. As the bay floods northeast out the slough, it would reach into the adjacent suburbs, which are less than 5 feet above sea level.
Although the water wouldn't rise as high in most other areas, it would cause some flooding through most of the two counties. Northern Broward County, west of Federal Highway, would stay relatively dry because most of that area has an elevation greater than 10 feet above sea level.
It's possible none of this flooding will take place. The sea may stop rising. Governments could get together and sharply reduce emissions of greenhouse gases. And even if sea levels do rise 5 feet, there are several things cities can do to keep out the ocean, such as constructing dikes or elevating land.
"It's not really accurate to say these areas are going to be under water," said Titus, the EPA sea-level expert. "People are going to do something about it."
Environmentalists have severely criticized the Bush administration for failing to take steps to reduce emissions from the two biggest sources of greenhouse gases, power plants and automobiles. The administration has rebuffed proposals to regulate carbon dioxide as a pollutant or to increase mileage standards for cars.
"This analysis should prompt people in Florida to demand that the Bush administration support reasonable programs to control the causes of global warming," said Daniel Lashof, science director for the climate center at the Natural Resources Defense Council. "The local governments should plan for the fact that sea level is going to rise in the future. But the amount it's going to rise depends on the changes we make to control the pollution that causes it."
EPA spokesman John Millett said the administration has taken several steps to reduce emissions of greenhouse gases. The administration initiated the Climate Leaders program, which has persuaded dozens of companies to make voluntary reductions in greenhouse gases. The administration's Energy Star program encourages the manufacture of energy-efficient consumer goods and accounts for a reduction in pollution comparable to getting 10 million cars off the road, he said.
"The president set a goal of reducing greenhouse gases by 18 percent over the next 10 years and to review the science and determine what are the next steps to take," he said.
Hulsey, the planner who drafted the South Florida study, noted that individuals can take steps to reduce their own impact on the environment.
"I recycle and I drive a Toyota Prius," he said, referring to an electric-gas hybrid that gets 52 miles per gallon. "And I turn out lights when I'm not in the room. And I do whatever little things I can as an individual to use energy more efficiently in an effort to pass the sleep-at-night test when it comes to things like global climate change."
David Fleshler can be reached at email@example.com or 954-356-4535.