A rainbow over Hoskinstown.

A rainbow over Hoskinstown. Photo: Kate Leith

An unusually strong La Nina producing record rainfalls has increased the number of climate change sceptics and is a ''nightmare for politicians'', according to one of Australia's leading climate scientists.

The co-director of the University of New South Wales Climate Change Research Centre, Professor Andy Pitman, says increased storm activity and floods have confused Australians who erroneously link climate change with drought.

The combined average Canberra city rainfall for January and February is 110mm but already more than 130mm has fallen on the capital this year. In Sydney more than 80mm of rain fell on the northern beaches on Monday.

Weather in Civic.

Weather in Civic. Photo: Andrew Sheargold

''The percentage of the population that believes in global warming varies seasonally, so if you have a hot summer more people believe in global warming, if you have a cold winter less people believe in global warming,'' Professor Pitman said.

''But global warming theory says weather will become more variable. It does not say it will only become hotter. Climate scientists have been saying for decades - more floods and more droughts, more heat waves and some extremely cold events.''

To tackle carbon emissions (the cause of climate change) Australia will set a carbon price from July 1, 2012 as an interim measure until a full emissions trading scheme can be introduced.

Yue Li waits for a bus under heavy skies after leaving work at Geoscience Australia in Symonston.

Yue Li waits for a bus under heavy skies after leaving work at Geoscience Australia in Symonston. Photo: Stuart Walmsley

Professor Pitman said recent weather along the east coast of Australia was within the ''classically defined characteristic of a La Nina''.

''Electorate support varies on whether it's been a hot summer or cold summer. That puts politicians in a nightmare scenario,'' he said.

Weatherzone meteorologist Doug Fenton expects above average rainfall along Australia's east coast, including Canberra, until April.

''We're experiencing a second La Nina summer in a row, so we're essentially getting more moisture in across from the Pacific with the trade winds, so more moisture means that when we get triggers for rainfall, it's heavier,'' Mr Fenton said. ''The La Nina event is remaining well established and we're not expecting it to return to neutral conditions until March or April which means there is likely to be above average rainfall for eastern Australia.''

The chief investigator at the Australian Research Council Centre of Excellence for Climate System Science Professor Matthew England said the intensity of the La Ninas in the past two years has been unusual.

''Last decade there were a couple in a row but what's unusual is that the La Nina last year was one of the strongest ever recorded,'' Professor England said.

''The waters off the coast of Australia were the warmest ever measured, so those aspects are unusual.''

The Bureau of Meteorology predicts a maximum temperature of 24 degrees in the territory today with a 60 per cent chance of rain and afternoon thunderstorms.