TAMPA BAY, Fla. — Mark Luther’s dream home has a window that looks out to a world of water. He can slip out the back door and watch dolphins swim by his private dock. Shore birds squawk from nearby nests in giant mangroves.

He said it’s hard to imagine ever leaving this slice of paradise on St. Petersburg’s Bayou Grande, even though the water he adores is starting to get a little creepy.

Over the 24 years since he moved into the house, the bayou has inched up a protective sea wall and crept toward his front door. As sea level rises, a result of global warming, it contributes to flooding in his Venetian Isle neighborhood and Shore Acres, a neighboring community of homes worth up to $2.5 million, about 70 times per year.

“Why stay?” asked Luther, an oceanographer who knows perfectly well a hurricane could one day shove 15 feet of water into his living room. “It’s just so nice.”

Tampa Bay is mesmerizing, with 700 miles of shoreline and some of the finest white sand beaches in the nation. But analysts say the metropolitan area is the most vulnerable in the United States to flooding and damage if a major hurricane ever scores a direct hit.

A Boston firm that analyzes potential catastrophic damage reported that the region would lose $175 billion in a storm the size of Hurricane Katrina. A World Bank study called Tampa Bay one of the 10 most at-risk areas on the globe.

Yet the bay area – greater Tampa, St. Petersburg and Clearwater – has barely begun to assess the rate of sea-level rise and address its effects. Its slow response to a major threat is a case study in how American cities reluctantly prepare for the worst, even though signs of impacts from climate change abound all around.

politics downplays risk

State leaders could be part of the reason. Republican Gov. Rick Scott’s administration has discouraged employees from using the words “climate change” in official communications. Last month, the Republican-controlled state legislature approved bills allowing any citizen to challenge textbooks and instructional materials, including those that teach the science of evolution and global warming.

The sea in Tampa Bay has risen naturally throughout time, about an inch per decade. But in the early 1990s, scientists say, it accelerated to several inches above normal, so much that projections have the bay rising between 6 inches and more than 2 feet by the middle of the century and up to nearly 7 feet when it ends. On top of that, natural settling is causing land to slowly sink.

Sea-level rise worsens the severity of even small storms, adding to the water that can be pushed ashore. Hard rains now regularly flood neighborhoods in St. Petersburg, Tampa and Clearwater.

By a stroke of gambler’s luck, Tampa Bay hasn’t suffered a direct hit from a hurricane as powerful as a Category 3 or higher in nearly a century. Tampa has doubled down on a bet that another won’t strike anytime soon, investing billions of dollars in high-rise condominiums along the waterfront and shipping port upgrades and expanding a hospital on an island in the middle of the bay to make it one of the largest in the state.

Once-sleepy St. Petersburg has gradually followed suit, adorning its downtown coast with high-rise condominiums, new shops and hotels. The city is in the final stages of a plan to build a $45 million pier as a major attraction that would extend out into the bay.

Worried that area leaders weren’t focused on the downside of living in a tropic, the Tampa Bay Regional Planning Council reminded them of the risks by simulating a worst-case scenario hurricane, a Category 5 with winds exceeding 156 miles per hour, to demonstrate what would happen if it entered the Gulf of Mexico and turned their way.

The fictitious Phoenix hurricane scenario projects that wind damage would destroy nearly half a million homes and businesses. About 2 million residents would require medical treatment, and the estimated death toll, more than 2,000, would top the number of people who perished from Hurricane Katrina in Louisiana and Mississippi.

Florida’s most densely populated county, Pinellas, could be sliced in half by a wave of water. The low-lying county of about a million is growing so fast that there’s no land left to develop, and main roads and an interstate connecting it to Tampa get clogged with traffic even on a clear day.

“If a hurricane 4 or 5 hit us,” St. Petersburg City Council Chairman Darden Rice said, referring to the two highest category storms, “there’s no doubt about it. The plan is you’d better get out of Dodge.”

Tampa Mayor Bob Buckhorn’s warning was even starker.

“Where you’re standing now would be 15 feet under water,” he said.

Video simulations of hurricanes that strafed Florida but missed Tampa Bay look like an epic game of dodgeball.

“It’s like we’re in this sweet spot. It’s like we’re blessed somehow, protected,” said Allison Yeh, a planner for Hillsborough County in Tampa.

The last direct hit from a Category 3 in 1921 left the area in ruins, but few people lived there then. One death was recorded.

RISING SEAS AND STAKES

Now, with 4 million residents and gleaming new infrastructure, the stakes are higher, and Yeh and her fellow planners are wary. They know a major hurricane like one of several that missed the bay in recent years would have a devastating effect.

There are few hurricane-proof buildings in the bay area. One is a gallery, the Salvador Dali Museum in downtown St. Petersburg with 18-inch-thick concrete walls and pressured glass supported by steel frames that could withstand anything the aforementioned storms could dish out.

The museum is better protected than one of the largest hospitals in the state, Tampa General, which sits on Davis Island, a spit of earth that was dredged from muck at the bottom of the bay a few years after the last hurricane hit. Buckhorn said a Category 3 hurricane would level the island’s houses, including his own.

Tampa General has a thorough evacuation plan, indoor generators that can supply energy for several days and safe floors with reinforced walls and windows.

But parts of two bridges that lead to and from the island would be cut off by floodwaters, a concern of officials in spite of assurances by the hospital’s managers that there’s a contingency for that too.

Floridians view hurricanes with the same bravado of Oklahomans who face tornados and Californians who brave earthquakes and wildfire: They come with the territory, a fact of life in a tropic, they say.

But other problems are less abstract than big hurricanes. Sea-level rise doesn’t need a megastorm to make its presence felt.

Water is bubbling up all over Florida. Within the next 12 years, according to an assessment by a group of researchers, Risky Business, the value of state property that will vanish under encroaching water could reach $15 billion. By 2050, it could reach $23 billion.

Along the barrier islands that lured more than 6 million tourists who spent nearly $10 billion last year, governments spend a mix of local and federal funds to renourish beaches lost to erosion that even a tropical storm can cause.

“The bay’s getting higher and the bay needs to go somewhere else. But there’s nowhere for the water to go,” said Mark Hafen, a University of South Florida associate professor who specializes in environmental science and coastal planning.

A team of planners in Hillsborough County said they fight against the potential impact of rising water every day, creating alternative bus routes and detours for flooded roads and trying to get the message out to residents in low-lying areas that their homes could be ruined.

“You live in a paradise and that’s wonderful, but it has storms,” said Eugene Henry, mitigation manager for Hillsborough County. He preaches about improved coastal inspection, color-coded warnings for residents depending on how low their homes are in a flood zone, making them more aware of the threat so they can take steps to protect themselves.

Planners in Tampa Bay are noticing that floodwater is sticking around longer. As the water rises, it’s filling huge outfall pipes, pushing water that would flow down a storm drain back onto streets.

Tampa and Hillsborough County officials have considered levying a tax to help fix a growing problem, but in a state where Republicans opposed to taxes control the governor’s office and the legislature, that’s a tough sell.

“We do have a real challenge with our storm water drainage system,” said Beth Alden, the executive director of Hillsborough Metropolitan Planning Organization.