The New York Times

The New York Times

September 14, 2004

As Weather Shifts, Beaches May Pay a Heavy Price

By CORNELIA DEAN

Coastal geologists, meteorologists and other experts have long warned Floridians not to rely on the relatively placid weather that prevailed in the last few decades, when their state grew explosively. Now the hurricane pattern is shifting, meteorologists say, and the shift has dangerous implications for the beaches - and the coastal hotels, roads and condominiums - on which Florida's tourism economy depends.

It has been decades since Florida suffered anything like the one-two punch of Hurricanes Charley and Frances, never mind Hurricane Ivan. But if repeated storms become regular events, as they were in the 1940's and 50's, the effects are likely to be devastating, these experts say.

"People who grew up around here talk about how when they were kids they were regularly sweeping sand out of people's homes," said Dr. Stephen P. Leatherman, director of the International Hurricane Research Center at Florida International University, speaking of the era before the surge of development along Florida's Atlantic and Gulf Coasts. Now the weather patterns of those years seem to be returning, Dr. Leatherman said.

More frequent hurricanes would be a problem not only for Florida, of course. But they would be particularly worrisome there. Coastal development is heavy and its coastal elevations are low: typically five feet or less, too little to offer much protection against a hurricane storm surge.

Also, many of Florida's coastal communities have relied for years on projects to pump sand onto beaches weakened by erosion, which afflicts most of the state's coast, a third of it critically, the state Department of Environmental Protection said. Erosion will accelerate as global warming causes sea levels to rise. More intense hurricane seasons will make beach replenishment, already a problem-filled and expensive proposition, even more difficult.

The state's renourished beaches survived the recent hurricanes relatively well, said Richard E. Bonner, deputy district engineer for project management for the Jacksonville District of the Army Corps of Engineers, which covers Florida, Puerto Rico and the Virgin Islands. "There's erosion, but of course that's what we expect," Mr. Bonner said. He and other coastal engineers often describe renourished beaches as "sacrificial": designed to protect buildings behind them, even as they erode.

But in places on Florida's east coast, Mr. Bonner said, Hurricane Frances has left beaches with what geologists call their winter profile, the shape they have after harsh winter weather has eroded them, and before gentle summer weather carries sand back on shore. As a result, these beaches will be more vulnerable to northeasters, winter storms that typically cause even more erosion than hurricanes.

Mr. Bonner and other experts said the effects on beaches from the recent storms were more widespread on the east coast of Florida than on the west. Hurricane Charley, which made landfall on the west coast on Aug. 13, was stronger - a Category 4 hurricane on the 1-to-5 Saffir-Simpson scale of intensity - but it was quite small and it moved fast. So its damage was concentrated, and much of it occurred on stretches of beach with relatively little development. Hurricane Frances, though only a Category 2 when it struck the east coast on Sept. 4, was a sprawling storm that, as Mr. Bonner put it, "hung around for a couple of days and beat the heck out of us."

In places where beaches were already weakened by erosion, Mr. Bonner said, dunes were cut and sand washed over onto roads behind the beach. In places, it even washed onto the main road along the barrier islands that line Florida's east coast.

Although Mr. Bonner said he was not yet convinced that weather patterns had changed, he said communities that did not replenish their beaches would lose them as rising seas moved in on shoreward structures like seawalls and revetments.

But beach renourishment projects can cost tens of millions of dollars and require constant maintenance.

"It's a long-term commitment," said Dr. Abby Sallenger, an oceanographer at the United States Geological Survey in St. Petersburg, Fla. "Once you start it, if you get hit by a series of storms in rapid succession you may have to replenish sooner than you thought. It's very expensive."

Florida towns are already arguing over shoals and other offshore sand supplies and going as far afield as the Bahamas to obtain sand for beach building. Dr. Leatherman said the city of Hollywood was even considering adding smooth ground glass to replenishment sand. "They are running out of good supplies of sand; that's no secret," he said. Mr. Bonner said the corps of engineers was considering using sand from inland sources to nourish beaches.

Plenty of people say it would be better if Floridians had not built so many of their homes, hotels and businesses right on the beach. But no one thinks they will remove them any time soon, regardless of weather patterns. In fact, although data on reconstruction after disasters is relatively slim, research suggests that people not only replace buildings destroyed in natural disasters, but they also tend to rebuild them bigger and better, said Dennis S. Mileti, former director of the Natural Hazards Center at the University of Colorado and author of the 1999 book "Disasters by Design."

"Unless there is total destruction, which there rarely is, buildings that are undamaged are an impetus to rebuild stuff that is already gone," Dr. Mileti said. "One of the biggest constraints to relocation after disasters is that not everything is damaged."

There may be calls for stiffer construction standards and other efforts to mitigate future damage, but some experts say that this kind of effort, along with loans and other disaster relief programs, only encourages more building.

One problem, Dr. Mileti said, is that people and political systems do not cope well with what he calls "high consequence/low probability" events. "It's what has us walk across the street even though we know people get hit by cars," he said. "The average person cannot take on worrying about or making very salient for themselves a high consequence/low probability event."

Also, he and other experts say, public attention turns to problems like coastal development just after disasters like hurricanes, but the focus is on individuals and their needs rather than policy changes like relocation incentives and setback requirements that would take people out of harm's way.

In any event, many experts say, efforts to mitigate the effects of natural hazards can never make a place like the coast of Florida completely safe. "Mitigation has limited applications," Dr. Mileti said, and may have the unintended consequence of making people feel safer than they really are.

Max H. Bazerman, a professor of business administration at the Harvard Business School, describes the situation in Florida as a "predictable surprise" - a problem anyone can see develop but no one wants to confront. Dr. Bazerman and his co-author, Michael Watkins, discuss the phenomenon in their book "Predictable Surprises," to be published this month. Dr. Bazerman said he doubted that people even considered hurricanes when they moved to the Florida coast. "I think the more likely story," he said, "is that people sort of want to build on the ocean and they don't even think about those risks. We have limited awareness of factors that we don't want to bring into consideration."

The weather in recent weeks "doesn't mean we should abandon Florida," Dr. Mileti said. Instead, he and other experts say, Floridians should build - or rebuild - "in ways that are consistent with the forces of nature," basically by keeping high-density development off the beach. But for that to happen, they say, it will be necessary to draw the public's attention to the issue, not when emotions are running high in the aftermath of a storm, but later, when local and state agencies consider development proposals and master plans.

The problem, Dr. Leatherman said, is that with a few exceptions, like the theme parks around Orlando, the state's economic base is concentrated on the coast. "The real value is packed along the shoreline, and the magnet is the beaches," he said. "And this is hurricane alley."