02/01/08 (NZ):
Climate Change Debate Rumbles On Down Under
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Many scientists believe that greenhouse gasses are leading to global climate change and are damaging animal and plant life - and that it will get much worse. However, there are still those who are harder to convince.
Leading the charge internationally is former United States vice-president Al Gore and his documentary film 'An Inconvenient Truth'.
But in an often bitter debate, sceptics argue the science on climate change is not settled.
Instead, they say international government climate change policies will cost billions to solve a problem that in all probability does not exist.
New Zealand electricity consultant Bryan Leyland recently led a team of international sceptics to a climate conference in Bali. He maintains the world has not warmed in the past nine years and that the only evidence of global warming is computer models which he calls "junk".
Mr Leyland says the Bali conference was "more about politics than science".
Mr Gore's speech in Bali contained dozens of errors, according to sceptic Viscount Monckton of Brenchley, who was an expert witness in a recent court case in the UK (previously reported in last November's X-Pro News) in which a senior judge ruled that there were nine serious scientific errors in 'An Inconvenient Truth'.
However, Victoria University geologist and Antarctica expert Peter Barrett says the world's best scientists, in the United Nations' Intergovernmental Panel on Climate Change, say the climate is already changing, causing widespread damage to plants and animals.
Professor Barrett, a leader of drilling projects studying the history of Antarctica, says evidence is strong that the main cause of climate change is carbon dioxide, at eight billion tonnes a year and rising, mostly from fossil fuels.
The amount of carbon dioxide is alarming because it is rising above levels last seen three million years ago in the Pliocene "warm period", when sea levels were 25 metres higher than at present, he says.
Professor Barrett says the full effects of higher CO2 will be centuries away, but signs of that eventuality will become more obvious in just a few years, though he concedes that the whole planet is not warming. He says that the three main areas are the Arctic sea ice, Siberia and the Antarctic Peninsula. Since pre-industrial times, global temperatures have risen 0.7C.
Sceptics say the world is actually cooler now than in the so-called Medieval warm period 1000 years ago. They also say that today's temperatures are not unusual or unnatural.
During last summer, as in many other years, Arctic sea ice shrank to worrying levels but returned to normal levels in winter, but according to some predictions, the area could be ice-free by 2040.
Professor Barrett says that just because summers are warmer, winters are not necessarily warmer as well. He says the Antarctic is melting about 100 cubic kilometres a year, equal to a sea level rise of about 0.4 of a millimetre a year (plus or minus 0.2mm).
© X-Pro 2008
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