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No firm link yet between human-caused global warming and intensity of cyclones – UN

No firm link yet between human-caused global warming and intensity of cyclones – UN

Despite a recent increase in dangerous typhoons and hurricanes, no firm link can yet be drawn between human-induced climate change and variations in intensity and frequency of tropical cyclones, the United Nations World Meteorological Organization (WMO) has reported, citing a consensus of 125 leading researchers and forecasters.

Despite a recent increase in dangerous typhoons and hurricanes, no firm link can yet be drawn between human-induced climate change and variations in intensity and frequency of tropical cyclones, the United Nations World Meteorological Organization (WMO) has reported, citing a consensus of 125 leading researchers and forecasters.

The recent increase in loss of life and damages from tropical cyclones has largely been caused by rising concentrations of population and infrastructure in coastal regions, WMO said in a news release summarizing the results of its 6th international workshop on tropical cyclones held in Costa Rica last month.

Although the accuracy of tropical cyclone monitoring has improved considerably over the last few decades, large regional variations exist in methods used to monitor tropical cyclones, and several regions have no measurements by specialized aircraft. These factors continue to make detection of trends difficult, it added.

In 2008, WMO will launch over the Pacific Ocean, the international THORPEX Pacific Asia Regional Campaign (TPARC) in cooperation with the tropical cyclone research and forecasting community in a bid to accelerate improvements in the accuracy of numerical weather prediction, probabilistic forecasting and the understanding of tropical cyclones.

WMO noted that as indicated in the third Intergovernmental Panel on Climate Change Assessment Report sea levels are predicted to rise by between 9 and 88 centimetres by the end of the 21st Century in connection with global warming and such an increase would heighten coastal vulnerability to flooding from tropical cyclone storm surges.

A number of recent high-impact tropical cyclone events around the globe have occurred in recent years, including 10 typhoons that made landfall in Japan in 2004; five affecting the Cook Islands in a five-week period in 2005; Cyclone Larry in Australia, Typhoons Saomai and Durian in China and the Philippines respectively this year; and the extremely active 2004 and 2005 Atlantic hurricane seasons.