Extreme weather patterns pose greater insurance risk.

A continuing pattern of weather extremes and increasing severity of natural catastrophes in 2003 poses a "deteriorating risk situation" that insurers will have to address, Munich Re Group said in its year-end catastrophe survey.

The world's largest reinsurer said 2003 was marked by a series of severe natural hazard events, with the number of fatalities far exceeding the long-term average. According to Munich Re, more than 50,000 people were killed in natural catastrophes worldwide in 2003, up from 11,000 the previous year. It was the highest death toll in one year for natural catastrophes since 1980, Munich Re said.

Economic losses from natural catastrophes rose to $60 billion from $55 billion in 2002, resulting mainly from tornadoes, heat waves and forest tires, plus severe floods in Asia and Europe. Insured losses rose to $15 billion from $11.5 billion, with the series of tornadoes in the Midwest in May alone costing insurers more than $3 billion.

The four largest events in terms of insured losses were all in the United States: the series of more than 400 tornadoes that swept across the Mid-West; the California wildfires; Hurricane Isabel; and storms that dumped snow and ice across the Midwest and Northeast in April.

One disturbing aspect of the 2003 catastrophe scenario is the emergence of extreme heat waves as a damaging force, said Munich Re. Extreme heat that enveloped much of Europe in August caused an estimated $13 billion in economic losses and possibly as many as 20,000 deaths. According to Munich Re, insured losses were small, but pinning down the exact amount is difficult, since it is difficult to determine how many claims can be tied directly to the heat wave.