From floods that crippled countries, to mega cyclones, huge blizzards, killer tornadoes to famine-inducing droughts, 2011 has been another record-breaker for bad weather.

While it is too early to predict what 2012 will bring, insurers and weather prediction agencies point to a clear trend: the world's weather is becoming more extreme and more costly.

Following are details of major weather disasters for 2011 and some early forecasts for 2012.


Global reinsurer Munich Re says natural catastrophe losses for the first nine months of 2011 totaled $310 billion, a record, with 80 percent of all economic losses occurring in the Asia-Pacific region. Since 1980, weather-related disasters globally have more than tripled.

The United States set a record with 12 separate billion-dollar weather disasters in 2011, with an aggregate damage total of approximately $52 billion, the National Oceanic and Atmospheric Administration said this month.


A La Nina event in the Pacific Ocean is expected to last well into 2012. The phenomenon is a cooling of waters in the central Pacific and has a global impact on weather.

Forecasters expect it to bring above-average rains to northern and eastern Australia and more cyclones than normal during the Australian November-April storm season. La Nina events also tend to strengthen the Atlantic hurricane season.

Colorado State University researchers expect an above-average hurricane season if conditions that bring warmer than usual tropical water temperatures in the Atlantic persist and there no major El Nino event. El Nino is a warming of surface waters in the eastern and central Pacific, affecting wind patterns that can trigger droughts in Australia and suppress Atlantic hurricanes.

Winter across Europe and the United States is also expected to be milder, forecasters say.
"The common thread this winter compared to last is the presence of La Nina," said Chris Vaccaro, public affairs director, at the National Weather Service in Washington. "But the La Nina we have now and through the winter is not anticipated to be as strong as last year."

In addition, the Arctic Oscillation, which was negative last year and sent frigid air southward leading to huge snowstorms, has largely been positive this year. The oscillation is a shift in atmospheric pressure cells that changes wind patterns.

A negative phase triggers high pressure over the Arctic and low pressure at mid-latitudes, which makes the Arctic zone relatively warm, but spills cold Arctic air southward to places like the U.S. Midwest and Northeast.

Source: Reuters