A study by coastal planning researcher Peter Helman says the east coast of Australia has entered a new weather phase during which regular rain, wind and damaging storms will follow recent years of drought.

Dr Helman and retired Bureau of Meteorology extreme weather forecaster Jeff Callaghan spent the past decade tracking weather patterns dating back more than 200 years by reading diaries and accounts from pioneers such as Captain Cook.

Plotting weather patterns on a timeline, they found Australia's climate has two distinct phases lasting about 30 or 40 years.

"We can see there are periods of storms and floods that last for a few decades, such as the decades leading up to . . . the 1974 floods in Brisbane," Dr Helman said.

"They are followed by a period of very little rainfall and plenty of drought, which we've definitely seen here in the last 30 years."

He said the wet and dry phases were affected by variations.

Timelines were not precise, but the study over about 200 years showed a clear distinction between the two.

"What has happened [last] week with the storms in south-east Queensland does not mark the start of decades of storms but it does indicate the change in climate is under way," he said.