Monday, June 8, 2009

Fielding feels heat over solar flare theory

By Emily Bourke for The World Today

ABC News Online, Posted Mon Jun 8

Family First Senator Stephen Fielding is under fire from the scientific community over his new-found belief that solar flares - not human activity - might be responsible for climate change.

Fresh back from a study tour of climate change in America, Senator Fielding says he is now doubting the science on the links between global warming and carbon emissions.

Climate scientists here say Senator Fielding has been misinformed by American climate change deniers and revisiting the solar flare theory is a wasting valuable time.

Senator Fielding says he is open-minded, but he believes the science on solar activity is compelling.

"Is carbon emissions really the major driving force of global temperature change?" he said.

"What I heard at the conference is that solar activity seems to be more closely aligned to global temperature changes over a long period of time."

Senator Fielding will be taking the issue up with Climate Change Minister Penny Wong this week when they meet for talks on the Government's carbon pollution reduction scheme bill.

"I intend to take some of the graphs and the charts that I've got from Tuesday, and ask her to explain why what they've put forward isn't credible," Senator Fielding said.

"I think that's fair enough. I think to question things is a positive thing.

"The big question that I've got; what happens if what they're saying is true?"

An old debate

Graeme Pearman, who is former chief of atmospheric research at the CSIRO, says the solar flare debate has been around for a long time.

"Senator Fielding might have just learnt about it, but in fact the science community has been aware of it for many years," he said.

"The changes of output of the sun are well and truly documented. We've been observing this for over a hundred years.

"We understand that there was probably some warming earlier last century, due to changes of emissions from the sun, but no evidence that the recent warming is due to that.

"And therefore there's no anticipation that that will be a major factor through this century."

Worldwide cooling?

One proponent of the solar flare theory is Phil Chapman, an Australian-born geophysicist and former NASA astronaut scientist.

"The sun is extremely quiet. There are very few spots, much less than we expect," he said.

"The implication is that if this continues, we're going to see worldwide cooling rather than warming."

He says the theory is that when the sun is not active, its magnetic field shrinks.

"That means that more cosmic rays get through to the earth from out in the galaxy," he said.

"And the cosmic rays, when they stop in the atmosphere, tend to produce clouds, and the clouds reflect sunlight back into space.

"So when you have fewer sunspots you have more clouds and therefore cooler weather."

Dr Chapman is warning against policies to reduce carbon emissions.

"The fact is that everyone that's looked at the data recognises that the climate has simply not been warming since 2002," he said.

"Whether that's going to continue, nobody can tell, but until we do know it is really foolish to start spending money."

Theories 'rubbish'

Dr Pearman says the theories about the climate cooling down in recent years are not to be taken seriously.

"It's absolutely rubbish. What that is referring to the fact is that last year's temperature was cooler than it was 10 years ago," he said.

"The year to year variation of the planetary mean temperature has been two or three tenths of a degree, and the trend that we've seen over the last 100 years is only one tenth of a degree per decade.

"So, if you only look at one 10-year period, you're never going to be able to see the trend. You have to have a longer period of observations."

David Karoly is a professor of meteorology at the University of Melbourne.

He says the source of Senator Fielding's new-found knowledge - the American Heartland Institute - deserves closer inspection.

"It is very surprising that he doesn't accept the best information from scientific assessments... but seeks to get his information from a group of climate change deniers, an organisation that's receiving sufficient funding from the fossil fuel industry," he said.

"He seeks to accept their scientific misinformation more than he accepts peer-reviewed scientific publications."

While there might be some doubts over the causes of climate change, Dr Pearman is more concerned that revisiting the solar theory is wasting valuable time.

"We really don't have time to wait - we have to get on with it. That doesn't really mean that we're absolutely sure about everything that is projected in climate change," he said.

"There will be uncertainties always, but the potential magnitude of the change, and the high probability it will occur, means we simply have to stand up and manage that risk through both adapting to it and reducing our emissions."

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