The world this year suffered the fewest number of natural disasters in a decade, but floods, droughts and other extreme weather continued to account for most of the deaths and economic losses, according to a United Nations report released on Monday.

There were 245 natural disasters recorded this year, down from the decade high of 434 in 2005, said the UN International Strategy for Disaster Reduction. The figures were released mid-way through an international climate conference in which 192 nations hope to nail down new firm targets for reducing carbon pollution, which is blamed for a long-term trend in more extreme weather. Of the 245 disasters, 224 were weather-related and accounted for 7,0000 deaths out of the 8,900, according to the preliminary figures.

The weather-related deaths, which exclude geological events such as earthquakes and volcanoes, caused $15 billion in damages, out of a total of $19 billion, the report said. The lower figures for 2009 were "good news", but "extreme weather disasters remain the top of the list and will continue to affect more and more people in the future" who are living in coastal regions, said Margareta Wahlstrom, the UN special representative of the Secretary-General for Disaster Risk Reduction.

Another UN study released on Monday said that by 2050, ocean acidity could increase by 150 percent and that by 2100, 70 percent of cold-water corals that are feeding grounds for commercial fish species will be exposed to corrosive waters. Last week, scientists at the Copenhagen international climate conference said oceans absorb about 25 percent of all carbon dioxide emitted by humans each year.

World Meteorological Organization Secretary-General Michel Jarraud said that progress in monitoring and forecasting extreme weather, along with improved emergency preparedness, has helped reduce fatalities. "While the numbers of disasters and related economic losses have increased between 10 and 50 times (over the last 50 years), the reported loss of life has dramatically been reduced by a factor of 10," Jarraud said. People living in Asia were especially vulnerable to storms and floods, the report said. It found that in the first 11 months of this year, 48 million Asians were affected, of the 58 million total.

Last week, the WMO said 2009 would likely be the fifth warmest on record and that the first decade of this century would be the hottest since record-keeping began in 1850. Major developed countries are hoping the Copenhagen meetings end this week with a promise to stop global temperatures from rising more than 2 degrees Celsius from pre-industrial levels. That goal, they hope, will rein in the extreme weather patterns scientists see intensifying in coming decades. But island nations, which increasingly are threatened by rising sea levels, want a more ambitious 1.5 degree lid.