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THE big wet may not be over for Queenslanders for another few decades, with the La Nina climate pattern tipped to be a repeat visitor.

Stewart Franks, associate professor in environmental engineering at NSW's University of Newcastle, said his research suggested "enhanced" La Ninas would dominate eastern Australian summer weather patterns for years to come.

"What we noticed is El Nino and La Nina events are actually not random, they tend to cluster, and they cluster on time frames between 10 to 40 years," he said.

Professor Franks, an Australian national representative to the International Association of Hydrological Sciences, said the last run of strong La Ninas occurred between the mid-1940s and mid-1970s, culminating in the 1974 floods.
They were followed by about three decades dominated by El Nino dry climate patterns.

"We are seeing a return to the devastating impact of the enhanced La Ninas we saw in 1945 to 1975, so that indicates to my mind that it's entirely possible that were facing 20 to 30 years of repeated, frequent or enhanced La Ninas," he said.

La Nina is a period where cooler than normal ocean temperatures in the central and eastern Pacific combine with higher winds and a cloudier atmosphere to change the weather patterns in Australia and South America.

Professor Franks, who has publicly challenged some of the world's top scientists on climate change, said successive La Ninas would result in far wetter summers and larger flood risks, particularly for the area from Rockhampton in Queensland to the NSW central coast.

While La Ninas tend to dissipate by April, the intervening months could still bring more monsoonal rain to soaked catchments, he warned.

The Bureau of Meteorology, which has attributed the Queensland floods to this year's La Nina, has put the odds of above average rainfall for southeast Queensland at 70 per cent for the first three months of this year.

Peter Baddiley, the bureau's Queensland flood warning service manager, said the risk of flooding would continue through to March. "You just cannot rule out the possibility of floods again in Queensland, possibly in different areas, possibly in the same areas," he said.

But Mr Baddiley said he doubted the state would see such severe wet weather again this summer.

"You need a special set of circumstances to create that level of record rainfall and flooding over such a wide areas and it would be really low in the odds to receive something of that scale again," he said.