Groups see Added Risks From Change in Climate

The effects of climate change, especially rising seas, threaten trillions of dollars’ worth of coastal property, and flood-hazard maps, zoning laws, building codes and insurance rates in the United States do not accurately reflect the risk, an unusual coalition of groups reported Thursday.

The coalition — organized by the Heinz Center, a research organization that focuses on environmental issues, and Ceres, an organization of environmentally conscious investor, insurance and other groups — said the nation had failed to take “reasonable steps” to reduce economic losses and protect residents of the coast.

In a report, it urged that government flood-hazard maps be updated and that local land-use policies bar people from building or rebuilding in areas at high risk of flooding.

Property owners should be encouraged to make their buildings more storm-resistant, the coalition added. It cited research by the Wharton School indicating that tougher construction codes could reduce damage from coastal storms by more than 60 percent.

Spokesmen for the coalition acknowledged at a telephone conference that the report’s recommendations were not new. But Mindy Lubber, president of Ceres, said she hoped the coalition’s broad range — a mix of investment, insurance, government and conservation groups — would bring “unique leverage” to the issue.

The coalition members, who are supporting one another’s initiatives, include insurance companies like Travelers and Fireman’s Fund, the Wharton School, the Nature Conservancy, the National Oceanic and Atmospheric Administration, Calvert Investments and other groups.

In an earlier interview, Sharlene Leurig, who manages the insurance program at Ceres, said storms in recent years had caused such immense economic losses along the coasts that many insurance companies had limited or even halted underwriting there.

Given that half of Americans live in coastal counties, “that is not a sustainable business plan,” Ms. Leurig said, adding, “They are stepping away from a sizable portion of their business.”

But she and other members of the coalition said federal and state efforts to help people obtain insurance at low rates were not the answer.

At the news conference, Ms. Leurig acknowledged that if insurance on coastal property were priced according to risk, premiums would rise, resulting in declines in values in some areas. Nonetheless, she said, insurance premiums can be a powerful tool for communicating risk to potential buyers.

In the telephone conference, the mayor of Charleston, S.C., Joseph P. Riley, pointed with pride to a county and city initiative that would restrict most development of Johns Island, a rural area south of the city, to a small part of its interior.

Mr. Riley conceded, however, that island residents were complaining that their property values would decline under the plan and that one developer had sued to block it.