Storms and floods were the drivers of natural catastrophe losses worldwide in 2002, according to Munich Reinsurance Co.

In its annual study of natural-catastrophe trends, the Munich, Germany-based reinsurer said insured losses from natural catastrophes amounted to $13 billion last year, a jump of 13 percent from $11.5 billion losses in 2001.

Zurich, Switzerland-based reinsurance giant Swiss Re also issued similar findings in its new study, which said floods caused record losses in 2002, costing insurers worldwide $4.1 billion.

Munich Re said significant natural-catastrophe events in the United States included tornadoes in April, which caused $1.6 billion in insured losses, and storms in November, which resulted in $460 million losses.