As Hurricane Sandy barreled toward the East Coast in late October, meteorologist Tim Doggett swung into action, poring through the latest weather information and racing to enter data into a powerful computer program before losing power.
But Doggett wasn’t preparing a weather forecast. Working in a row of sand-colored cubicles in the Back Bay, Doggett and his colleagues were trying calculate the amount of damage the storm could cause, even before it made landfall. The final estimate: as much as $22 billion in insured losses, making it the one of the costliest US storms on record.
“That one was crazy,” said Doggett, recalling the howling wind and quivering trees at his home in Wenham.
Doggett works for AIR Worldwide, a Boston company that uses computer models to help insurers determine the risk of losses from disasters and set rates accordingly. With some 450 employees, including 350 at its headquarters in the Back Bay, AIR Worldwide is one of the nation’s three major catastrophic risk-modeling firms, tracking damage from tornadoes, earthquakes, tsunamis, and — of course — hurricanes around the globe.
The models have become controversial, however, as insurers use them to justify rate increases, particularly near the coast. For instance, rates for homeowners’ insurance soared on Cape Cod starting a decade ago after the largest modeling company, Risk Management Solutions Inc. of Newark, Calif., boosted its estimates for the potential risk of a major hurricane slamming the Massachusetts coast.
Some homeowners worry that Sandy could encourage companies to revise models again and send rates even higher, even though the so-called super storm struck only a glancing blow to Massachusetts.
But AIR Worldwide and other modeling companies warn that the massive destruction in New York and New Jersey is a reminder that Massachusetts remains at risk of a once-in-a-century storm like the Great New England Hurricane of 1938, a category 3 storm that demolished countless homes and other structures throughout the region.
If the same storm hit today, it would be likely to cause even more damage because so many more expensive homes and buildings are built along the coast. AIR Worldwide estimates the 1938 storm would cause $33 billion in insured losses if it struck now — much more than Sandy.
“We can’t forecast that it will be this year, next year, or in the next few years,” said Jayanta Guin, senior vice president of AIR Worldwide. “But we know it will happen.”
The projections, already built into sophisticated risk models used by insurers, help explain why home insurance rates have become so expensive along the coast. Some insurers stopped offering coverage on Cape Cod altogether a decade ago. More than one-third of homeowners on Cape Cod and the Islands can’t find insurance on the open market and must instead rely on the state’s insurer of last resort, known as the Massachusetts FAIR plan.
Paula Aschettino, an Eastham homeowner who started Citizens for Homeowners Insurance Reform to fight higher insurance rates on the Cape, says her own annual insurance bill has more than doubled to $3,100 since 2000, even though she’s increased her deductible to $5,000.
Aschettino said she is particularly concerned about the information fed into models, wondering if modeling companies include storms that never made landfall as hurricanes in Massachusetts. Others question the use of shorter-term models, which show a higher risk of storms hitting the coast over the next few years.
“There are no standards in Massachusetts for hurricane models,’’ Aschettino said.
Similar concerns have popped up all along the Gulf Coast and Eastern Seaboard as insurance rates have soared over the past two decades. Florida created a commission in 1995 to monitor the methodology of modeling companies. State regulators across the country even looked into building their own public model to calculate the risk from hurricanes and earthquakes, but decided it would be too expensive.
Modeling companies insist the criticism is overblown. For one, they say, they don’t try to predict exactly where or when storms will hit, but just estimate the potential risk based on the best information available — data used by insurers, government agencies, and investors alike to prepare for the future.
Nor do models alone set rates. Insurers also consider their own loss histories and understanding of the risks. In addition, much of the cost of home insurance, especially away from the coast, is based on more routine hazards, such as fire or robbery, and considerations like competition.
But models have become a key part of the calculations over time. Demand for the projections mushroomed after Hurricane Andrew swept through Florida in 1992, causing billions of dollars in damage and prompting the failure of some small insurers that weren’t prepared for a disaster of its magnitude.
AIR Worldwide was one of the nation’s first catastrophic risk modeling companies when it was founded as Applied Insurance Research in 1987 in a small shared office on Tremont Street. Today, it fills two floors in a midrise office tower near Back Bay Station — and still it’s not enough to keep up with growth.
The company says it serves more than 400 insurers, reinsurers, brokers, financial institutions, government agencies, and other corporations — ranging from Liberty Mutual Insurance Co. to Walt Disney Co., which operates theme parks in Florida and earthquake-prone California. The firm was acquired by a larger risk assessment company, now called Verisk Analytics Inc. of Jersey City, in 2002.
In one sign of the company’s global reach, the offices are filled with foreign language dictionaries and maps from around the world, including France, Japan, and southeastern Florida (each of which have their own natural perils). “We’re running out of space — again,” said Guin.
Like other modeling companies, AIR Worldwide has compiled an extensive catalog of past storms and other disasters. But AIR Worldwide executives say they don’t want to rely on past experience alone because every storm is different.
Instead, they’ve tried to develop powerful computer models that can create new simulated storms, based on weather research and observations about how past storms have formed. Researchers then run the models countless times to figure out the possibilities over time.
“History is not enough,” said Guin.
But history can be frightening when you account for the “explosion of construction on the coast,” AIR Worldwide executives said. For instance, the Great Miami Hurricane —
AIR Worldwide estimates that New England is likely to be hit by a storm causing at least as much damage as Sandy every 100 years or so — a chance of 1 percent a year. Storms as damaging as the Great Hurricane of 1938 may occur less frequently — about once every 130 years.
Nearly 75 years have passed since a hurricane with that kind of destructive power hit Massachusetts. Many are convinced it won’t be the last.Todd Wallack can be reached at firstname.lastname@example.org. Follow him on Twitter @twallack.