QUEENSLANDERS should brace themselves for more cyclones, flooding and wild weather over coming months as a strong La Nina pattern settles in over the eastern states.
And weather experts predict the climate chaos could last even longer, with some forecasting the current cycle could remain in place for up to 30 years.
Stewart Franks, environmental engineer and scientist at the University of Newcastle, told The Australian yesterday that the category 5 Cyclone Yasi and recent major floods in Queensland were direct results of joint La Nina and Cold Pacific Decadal Oscillation weather patterns.
No one died in yesterday's cyclone despite the storm being larger than the devastating Hurricane Katrina.
However, more than 30 people lost their lives in the southern Queensland floods.
La Nina patterns are usually associated with above-normal rainfall across much of Queensland and enhanced tropical cyclone activity in the Coral Sea.
A Cool Pacific Decadal Oscillation pattern is one that lasts between 10 to 30 years and is detected by higher ocean surface temperatures.
"Through my research of more than 400 years of weather records, La Nina patterns are not random but instead occur in clusters of 10-30 years," Mr Franks said.
"What that means for Queensland is that there will be cyclones, floods and other La Nina-type weather, with the potential for it to be as strong or even stronger than what we have recently seen."
Mr Franks dismissed as "rubbish" speculation by several scientists that excess carbon dioxide in the atmosphere caused by man-induced climate change was responsible for La Nina.
"I get so frustrated because that idea is driven by scientists with a policy agenda and I don't think scientists should have policy agendas," he said.
Weatherwatch chief executive officer Don White disagreed.
"We've had La Ninas before and the bad ones normally come about every 25 or so years, but everything has been aggravated by global warming," Mr White said.
"Ocean temperatures are warmer now than they have been at any time in the last century -- that's why these massive weather events have come about."
Mr White said Queensland was "not out of the woods yet" and more storms this season were a given.
"It would be fair to say there will be further cyclones threatening northeast Australia and probably significant rain events over the next two to three months, which could lead to flooding again," he said.
A Bureau of Meteorology spokeswoman said Queensland could expect up to six cyclones this season alone.
"We are currently in a La Nina climate phase (so) . . . what this translates to is where historically we could expect an average of four cyclones a season in the Coral Sea, we now expect the number to be potentially higher," the spokeswoman said.
"It is also likely to be wetter than normal in most parts of Australia."
Climate expert and former Bureau of Meteorology operational forecaster Clem Davis told The Australian yesterday he believed La Nina conditions would last "at least until autumn" with the potential for further rainfall and cyclone activity across the eastern states.
"It is difficult to say how ferocious the conditions will be," Mr Davis said.
"But everything is certainly primed to produce more rainfall."
Mr Davis said Queenslanders should not fall into a false sense of security simply because they had experienced major weather events recently and think there would not be more to come.
"Just because the worst seems to have passed, people should not let their guards down," he said.
"If the ocean surface temperatures there and conditions match up we will see more severe storms."