The Courier-Mail
By: Graham Readfearn
New research reveals some surprises about climate change, Graham Readfearn reports.
Australian government climate experts have failed to detect an increase in the intensity of tropical cyclones after analysing 26 years of data since the early 1980s.
Climate scientists have warned that Australia should expect to see more intense cyclones in the future fuelled by rising global temperatures caused by greenhouse gases.
But the latest research from seven Bureau of Meteorology scientists shows there is no conclusive evidence to suggest this has started to happen already.
Scientists told The Courier-Mail the findings (which will fuel the debate among skeptics of human-caused climate change) did not indicate climate change would not cause an increase in the frequency of powerful cyclones in the future.
Appearing in the prestigious Journal of Geophysical Research Atmospheres, published by the American Geophysical Union, the scientific paper analysed satellite data and images for all the tropical cyclone seasons in Australia from 1981 to 2007.
The research concluded: "In the Australia region, no significant trends in the total numbers of Tropical Cyclones, or in the proportion of the most intense TCs, have been found.''
Co-author of the research, Dr John McBride, said: "We still expect more intense cyclones but we are comfortable with the fact that you cannot yet see that in the data.''
The research did find a positive trend in the numbers of the most intense cyclones in the Southern Indian Ocean region.
But the authors said while it was "possible'' that the trend could show climate change at work, this finding could instead be down to "changes in data quality''.
In theory, scientists say ongoing rises in ocean temperatures should see the numbers of intense cyclones increase.
Professor David Karoly, a world-leading climatologist at the University of Melbourne, said the research did not change this expectation.
"It's very, very difficult with a 20 or 30-year time scale to separate a climate change signal from natural variation. You would not expect to see a signal until about 2030.''
Last week Opposition Leader Tony Abbott criticised the Government's proposed emissions trading scheme, saying it should "not politicise events such as floods or cyclones to try to justify a new tax.'']
Mighty storms
4.7 tropical cyclones affect Queensland per year on average.
207 known cyclones have hit along the east coast since 1858.
Major east coast tropical cyclones include:
1890 Cardwell; 1893 Brisbane; 1898 NSW; 1899 Bathurst Bay; 1918 Innisfail; 1918 Mackay; 1927 Cairns and inland; 1934 Port Douglas; 1949 Rockhampton; 1954 Gold Coast; 1967 Dinah, Southern Queensland; 1970 Ada, Whitsunday Islands; 1971 Althea, Townsville; 1974 Wanda, Brisbane; and 2006 Larry, Innisfail.
Several tropical cyclones have hit the Gulf of Carpentaria region including
The 1887 Burketown cyclone, the 1923 Douglas Mawson cyclone, the 1936 Mornington Island cyclone; the 1948 Bentick Island cyclone and Cyclone Ted in 1976.
Source: Bureau of Meteorology