SCIENTISTS ARE reluctant to link individual weather events to global warming, because natural variability will always throw up extreme events. However, they say climate change loads the dice, and can make severe episodes more likely.
Some studies have started to claim how much global warming contributed to severe weather.
Experts at the British government’s Meteorological Office and Oxford University used computer models to say man-made climate change made the killer European heatwave in 2003 about twice as likely. In principle, the technique could be repeated with any extreme storm, drought or flood.
Bob Brown, a senator who leads the Australian Greens, said the bushfires showed what climate change could mean for Australia.
“Global warming is predicted to make this sort of event happen 25 per cent, 50 per cent more,” he told Sky News.
Models suggest global warming could bring temperature rises as high as 6 degrees for Australia this century, if global emissions continue unabated, with rainfall decreasing in the southern states and increasing further north.
As if to demonstrate that, Queensland, in the north, is experiencing widespread flooding after heavy rainfall.
Roger Stone, a climate expert at the University of Southern Queensland, said: “It certainly fits the climate change models, but I have to add the proviso that it’s very difficult, even with extreme conditions like this, to always attribute it to climate change.”
The fires and floods come as politicians gear up to negotiate a new global deal to replace the Kyoto protocol.
Australia plans a comprehensive carbon trading scheme, but green campaigners last year accused Kevin Rudd’s government of a “betrayal” when it pledged to reduce emissions by a modest 5-15 per cent by 2020.
Australia is in the grip of the worst drought in a century, which has stretched for more than seven years in some areas and has forced restrictions on water use in the country's big cities. – ( Guardian service)