Around one in five US residents lives within 10 miles of a coastline vulnerable to hurricanes and the coastal population — together with the risk for property catastrophe insurers and reinsurers — continues to grow.

That was the message from Aon Re's lead meteorologist Steve Drews yesterday, who told delegates at the Bermuda Captive Conference there was a growing complacency in large coastal communities that had been untouched by major hurricanes in recent years.

"People are thinking, 'it hasn't happened here in a while, so it's not going to happen to me'," Mr. Drews said during a session on hurricane prediction. "We've seen the population soar in places like Galveston, Tampa and Miami. It's like dangling food in front of a pitbull."

The 2000 US census found that 52 million people were living within 10 miles of hurricane-prone Atlantic or Gulf of Mexico coastline, Mr. Drews said, which amounted to 18.5 percent of the population living on a vulnerable one percent of US land area. There was no sign of a lessening of the problem of risk accumulation, with the fastest-growing areas in the US including areas prone to hurricanes, tornadoes, earthquakes and wildfires.

There were numerous lessons from history of the risks of building in unwise locations, he added. The category-five hurricane that hit Miami in 1926 caused $1.2 billion of damage at that time. If a similar storm made landfall in the same place today, it would cause an estimated $120 billion to $160 billion in losses, Mr. Drews said.

Similarly, the 1900 Galveston hurricane, if repeated today, would cause $40 billion to $80 billion in damages, while a repeat of the direct hit suffered by New York City in 1938 would cause $50 billion to $70 billion in losses. Even more recent lessons had not been heeded. For example, the city of Gulfport is now redeveloping on a large scale within a few feet of the coastline devastated by Hurricane Katrina's massive storm surge just three years ago.

"If you saw a sign saying 'no swimming' because of sharks, alligators or piranhas, you wouldn't swim there," Mr. Drews said. "Why can't we apply the same logic to where we are going to build?"

He said there had been a disconnect between builders, local authorities and insurers on the subject, which he believed boiled down to a matter of tax dollars and the desire to develop in spite of the risks.

Fellow panellist Anthony Knap, president and director of the Bermuda Institute of Ocean Sciences (BIOS), gave delegates a summary of the science behind climate destabilisation, looking at the effects of phenomena such as El Niño to the growing acidity of the ocean.

There was a scientific consensus that global warming was happening and that it was strongly influenced by human activity. One of the likely results was that Atlantic hurricanes would be more severe, if perhaps less frequent, Dr. Knap said. Winter storms would also become more frequent, something that was already showing up in meteorological records. In 2006-07, there were 64 Atlantic winter storms with winds of more than 60 knots, he said.

Sea levels were rising and some experts believed they could climb by as much as a metre by the end of the century, Dr. Knap said. He showed a map of Florida indicating a significant area at the southern tip of the state would be submerged by such a rise — exacerbating risk from hurricane-induced storm surges.

And yet each year humanity continues to churn out seven billion tonnes of carbon — about 25 times the combined weight of the world's population of 6.6 billion — thereby adding to greenhouse effect.

"It really has to move from talking to action," Dr. Knap said.

Asked by a delegate whether the earth was approaching any global warming tipping points, Dr. Knap referred to UK scientist Professor James Lovelock.

"Lovelock says that if we reach 500 parts per million of carbon dioxide — at the moment we're at about 370 — in the atmosphere, then we'll see runaway global warming," Dr. Knap said. "In 40 years we'll be at that level, so if he's right we're literally toast.

"People are wrong in saying it will be the end of the planet, it will just be the end of civilisation."