Lloyd's of London, the world's oldest insurer, offered a gloomy forecast of floods, droughts and disastrous storms over the next 50 years in a recently published report on impending climate changes.

"These things are fact, not hypothesis," said Wendy Baker, the president of Lloyd's America in an interview on Monday. "You don't have to be a believer in global warming to recognize the climate is changing. The industry has to get ready for the changes that are coming."

In a report on catastrophe trends Lloyd's is disseminating to the insurance industry, a bevy of British climate experts, including Sir David King, chief scientist to the British government, warn of increased flooding in coastal areas and a rapid rise in sea level as ice caps melt in Greenland and Antarctica.

Northern European coastal levels could rise more than a meter (3 feet) in a few decades, particularly if the Gulf Stream currents change, the report says.

Floods, which now account for about half of all deaths from natural disasters, could multiply and become more destructive, with annual flood damages in England and Wales reaching 10 times today's level, according to some studies.

At the same time, drought patterns that are already forming in some parts of the world are going to get worse, particularly in southern Africa.

Even the lush Amazon may dry up, and with less vegetation, more carbon dioxide will leak into the atmosphere, making the global warming problem even worse, the Lloyd's study says.

Baker said Lloyd's has formed a partnership with American International Group, the world's biggest insurer, Harvard University's Center for Health and the Global Environment and the Insurance Information Institute, a research group.

The four will hold a forum in the fall of 2007 to look at the severity and consequences of future natural catastrophes.

"The property casualty industry had an easy year in 2006, when there were no U.S. hurricanes," Baker said. "But the next one may make Katrina look inexpensive."

In August, 2005 Hurricane Katrina slammed into the U.S. Gulf Coast, costing the industry more than $38 billion and making it the most destructive storm in terms of property losses ever.

But hurricane modelers say a storm like Katrina hitting the Miami area of Florida or New York could cost as much as $100 billion.

Lloyd's was founded in 1688 and its 66 syndicates trade in London. But the United States is its biggest market with nearly 40 percent of its business.