U.K. insurance company Catlin Group Ltd. (CGL.LN) Monday said the worldwide string of natural disasters so far this year will make it the one of the worst ever for insurers.

The losses are bringing back memories of 2005, the worst year on record, when insurers suffered losses of around $50 billion across the industry, following Hurricanes Katrina and Wilma, which devastated the Atlantic coast of the U.S. and surrounding areas.

"In terms of aggregate dollar loss, 2011 looks like being the second worst after 2005," Chief Operating Officer Paul Jardine told Dow Jones Newswires. "What marks this year out is the frequency of natural disasters we've seen."

So far in 2011, major catastrophes in Japan, New Zealand and Australia have brought significant losses for insurance and reinsurance companies as claims have risen, while premiums have yet to reflect the increased level of risk.

Almost all London-listed insurance firms reported a half-year pretax loss this year as the number of claims soared and capital reserves were drained. Since then, floods in Thailand and Denmark, as well as losses from the Atlantic hurricane season, have made matters worse.

Catlin said its losses from natural disasters in the first nine months of the year came to $670 million, compared with $218 million in full-year 2010, adding it was still uncertain of the impact of the Thai floods. "There's been a lack of planning in Thailand and we're yet to see the extent of the losses," Jardine said.

After only six months, the 2011 damage bill worldwide was estimated to be higher at $60 billion, but a period of healthy investment returns and relatively few disasters since 2005 boosted capital levels, helping to cushion the impact of losses so far this year.

The industry has also been strengthened by rising premium rates for catastrophe-exposed business in the third quarter, with Catlin reporting an 11% increase in the three months to Sept. 30. Earlier Monday, fellow Lloyd's of London insurer Hardy Underwriting Bermuda Ltd. (HDU.LN) painted a similar picture, saying its ratings outlook was positive.

Jardine said premium rates look set to rise further in the new year. "I can see another similar [11%] increase on Jan. 1," he said.

-By Peter Evans, Dow Jones Newswires; 44-20-7842-9308; peter.evans@dowjones.com

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