Global warming: fact or hoax?

July 12, 2007

Global warming is caused by greenhouse gases: established truth or elaborate hoax? That's the question researchers at the University of New England are attempting to answer by analysing data ranging from historical sea levels to the cycles of the sun.

Associate Professor Robert Baker, of the university's PalaeoGroup climate change think-tank, said scientific evidence of higher-than-present sea levels about 3500 years ago was unequivocal. Whether recent global warming was caused by greenhouse gases or solar cycles was less clear, however, he said.

"Maybe, as some suggest, it was solar in the early part of the twentieth century, then greenhouse gas influenced since the mid-1980s. The jury is still debating the varied evidence," Dr Baker said.

Among Dr Baker's research tools is the tracking of the Southern Oscillation Index, which follows the 80-year Gleissberg solar cycle. This predictive tool was much better than currently-available short-term weather forecasting tools, he said.

"According to the SOI, we can expect above average rainfall for the next 12 months, followed by extensive flooding in 2008 and another drought phase in 2009," he said.

One of the principal projects of the PalaeoGroup over the last decade has been to investigate the links between sea level change and climate in the last 10,000 years (the Holocene) and their relative chronologies, concentrating on Australia and nearby regions, including South East Asia. Special attention has been given to looking for evidence of sudden climate or environmental change.

Dr Baker said that the "simple response" model of rising sea levels postulated by the global warming debate was not reflected by past events.

"The ocean current conveyor belt is far more complicated than the modelling suggests. Approximately 4000 years ago sea levels along the NSW coast were 1.7 metres higher and two degrees warmer. The whole of tropical Australia moved south. There is scientific basis to Aboriginal dreamtime stories of crocodiles in Moreton Bay.

"There is evidence from relic boulder beaches in northern NSW of more intense tropical cyclones penetrating further south. Likewise, 6000 years ago, in an earlier warmer period, dugong remains have been found in middens (including one found in Botany Bay) and coral remnants as far south as Wollongong."

Dr Baker said that members of the public who were interested in learning more about how solar cycles affected climate could visit the PalaeoGroup's website at http://www.une.edu.au/palaeogroup/.

For more information, contact Dr Robert Baker on (02) 6773 2884 or Leon Braun (UNE Public Relations) on (02) 6773 3771. A photograph is available to accompany this story.

Posted by Leon Braun at July 12, 2007 12:54 PM