Climate facts to warm to
March 22, 2008
Christopher Pearson From: The Australian
CATASTROPHIC predictions of global warming usually conjure with the notion of a tipping point, a point of no return.
Last Monday - on ABC Radio National, of all places - there was a tipping point of a different kind in the debate on climate change. It was a remarkable interview involving the co-host of Counterpoint, Michael Duffy and Jennifer Marohasy, a biologist and senior fellow of Melbourne-based think tank the Institute of Public Affairs. Anyone in public life who takes a position on the greenhouse gas hypothesis will ignore it at their peril.
Duffy asked Marohasy: "Is the Earth stillwarming?"
She replied: "No, actually, there has been cooling, if you take 1998 as your point of reference. If you take 2002 as your point of reference, then temperatures have plateaued. This is certainly not what you'd expect if carbon dioxide is driving temperature because carbon dioxide levels have been increasing but temperatures have actually been coming down over the last 10 years."
Marohasy: "Actually, no. The head of the IPCC (Intergovernmental Panel on Climate Change) has actually acknowledged it. He talks about the apparent plateau in temperatures so far this century. So he recognises that in this century, over the past eight years, temperatures have plateaued ... This is not what you'd expect, as I said, because if carbon dioxide is driving temperature then you'd expect that, given carbon dioxide levels have been continuing to increase, temperatures should be going up ... So (it's) very unexpected, not something that's being discussed. It should be being discussed, though, because it's very significant."
Duffy: "It's not only that it's not discussed. We never hear it, do we? Whenever there's any sort of weather event that can be linked into the global warming orthodoxy, it's put on the front page. But a fact like that, which is that global warming stopped a decade ago, is virtually never reported, which is extraordinary."
Duffy then turned to the question of how the proponents of the greenhouse gas hypothesis deal with data that doesn't support their case. "People like Kevin Rudd and Ross Garnaut are speaking as though the Earth is still warming at an alarming rate, but what is the argument from the other side? What would people associated with the IPCC say to explain the (temperature) dip?"
Marohasy: "Well, the head of the IPCC has suggested natural factors are compensating for the increasing carbon dioxide levels and I guess, to some extent, that's what sceptics have been saying for some time: that, yes, carbon dioxide will give you some warming but there are a whole lot of other factors that may compensate or that may augment the warming from elevated levels of carbon dioxide.
"There's been a lot of talk about the impact of the sun and that maybe we're going to go through or are entering a period of less intense solar activity and this could be contributing to the current cooling."