Insurance companies have taken flight -- for example, pulling out of many coastal areas in Florida, where the state is now the insurer of last resort. Total government exposure to storm-related losses in coastal states has risen more than 15-fold since 1990 to $885 billion last year, according to the Insurance Information Institute.

The Munich RE insurance group says North America has seen higher losses from extreme weather than any other part of the world in recent decades. Not all had to do with coastal events. But a year like 2005 (which included Hurricanes Katrina, Wilma and Rita) comes with a price of $60 billion in insured losses. That's the sort of number that drives up premiums.

In a report last month, Munich RE said: "A main loss driver is the concentration of people and assets on the coast combined with high and possibly growing vulnerabilities."

Risk Management Solutions, which models catastrophic risks, recently updated its scenarios, anticipating an increase of 40% in insurance losses on the Gulf Coast, Florida and the southeast over the next five years, and 25% to 30% for the mid-Atlantic and northeastern states. Those calculations were done pre-Sandy.

Getting more people out of harm's way is also a daunting challenge. As population density grows, so evacuation routes come under greater pressure. One out of Atlantic City this week was blocked by a stranded houseboat. More powerful storm surges threaten a wider area farther inland. And while forecasting the track of hurricanes has improved dramatically, forecasting their intensity has not. Hurricane Opel in 1995 went from a Category 1 to a Category 4 in just 20 hours.

This week, many people in the coastal townships of Ocean County were stunned by the speed and force of the surge. One resident told CNN how the water level rose from a couple of inches to waist height within an hour. Another recounted how a boat crashed into their porch, and then driven like a battering ram by the waters demolished their garage. In Brigantine, the owner of a marina said 50 of the 90 boats there had been scattered across the neighborhood.

Several homeowners lamented their lack of adequate flood insurance and their now tattered dreams of retiring to the shore. It's a fair bet that many households along the northeast coast will purchase such insurance -- through the National Flood Insurance Program -- in the coming months. After Irene the number of homeowners in the region with flood insurance rose from 5% to 14%.

Of the millions of people with jobs, businesses or vacation homes on the coast, or who just find the lure of the shore irresistible as a place to live, few will likely pack up and seek higher ground because of Sandy. They can buy insurance. But if the scientists are right, peace of mind might come at a premium.