Scientists question Coalition's climate change policy
The Coalition's climate change spokesman, Greg Hunt, is under attack from the science and research community who claim he has made a major error in his policy on emissions reductions.
TranscriptTONY JONES, PRESENTER: The Federal Coalition's Climate Change spokesman is under attack from scientists and researchers who claim he's made a major error in his policy on emissions reductions.
Last week Greg Hunt told Lateline that 150 million tonnes of carbon dioxide per year could be abated through soil carbon sequestration over a land area of just 100 square kilometres.
Mr Hunt now claims he was misunderstood and that he was talking about a much larger area of land, but critics say the Coalition's policy still doesn't add up.
Steve Cannane reports.
STEVE CANNANE, REPORTER: At the CSIRO in Adelaide, scientists are measuring soil carbon levels. It's work like this that will determine to what degree more efficient farming practices can increase soil carbon capture, something that could help reduce Australia's greenhouse gas emissions.
JEFF BALDOCK, CSIRO: To define the amount of carbon that we can get in soils we've got to consider two things: one is how much carbon we're putting into the ground and the other is how fast or how much of that carbon is being lost.
STEVE CANNANE: When native land is converted into agricultural land, carbon is released into the atmosphere. The carbon levels in soil drop on average by 40 to 60 per cent in the process.
But some of that carbon can be recaptured by reducing erosion, improving irrigation and fertilisation and turning some crops into pastures. Both sides of politics agree it has great potential.
JULIA GILLARD, PRIME MINISTER: We're going to have a system where they can get a new stream of income through carbon credits, through things like soil carbon.
STEVE CANNANE: But the Gillard Government doesn't count soil carbon in its targets because it's not Kyoto compliant.
The Coalition does count soil carbon. They're banking on it to deliver 60 per cent of their targets, up to 85 million tonnes in the year 2020.
In a recent interview on Lateline, Greg Hunt said an even greater figure could be achieved on a relatively small area of land.
GREG HUNT, OPPOSITION SPOKESMAN ON CLIMATE ACTION & ENVIRONMENT: We are talking about a land mass, if you are achieving the 150 million tonnes, of an area of roughly 100 square kilometres. Not tens of thousands, but 100 square kilometres of intensive agriculture would make an extraordinary achievement on many of the estimates.
STEVE CANNANE: But Lateline has spoken to experts in the field who dispute the claim.
MICK KEOGH, AUSTRALIAN FARM INSTITUTE: There's no science to indicate that it's achievable.
PETER COSIER, WENTWORTH GROUP OF CONCERNED SCIENTISTS: Well, I haven't seen any scientific evidence to suggest that they could achieve that volume of carbon.
STEVE CANNANE: The CSIRO would not comment directly on the Coalition's estimates. But its scientists can tell us how much carbon dioxide they believe can be abated per hectare.
JEFF BALDOCK: The best estimates that we've come up with right now, which is based on a fairly serious review of the scientific literature that's been published over the last 20 years or so, we see that on a C02 basis, somewhere between 0.3 tonnes of C02 equivalents per hectare per year, up to an upper limit of around about two tonnes of carbon per hectare per year on average.
STEVE CANNANE: Mick Keogh says that based on these estimates, Greg Hunt's figures don't add up.
MICK KEOGH: To reach the 150 million tonnes per annum of carbon dioxide equivalence would be 75 million hectares at the upside, that is at the two tonnes carbon dioxide equivalent per hectare per annum, or about 500 million hectares at 0.3, which is the lower level of the estimate.
STEVE CANNANE: But when I went back to Greg Hunt today, he said he defines 100 square kilometres as a hundred by a hundred, not 10 by 10.
GREG HUNT: When I talk about the 100 squared, that's all about a hundred by a hundred square kilometres or a hundred kilometres by a hundred kilometres, 10,000 square kilometres, a million hectares. You can play a game, respectfully, or we can be serious about what's the calculation here. A million hectares at a 150 tonnes of C02 equivalent per hectare is the figure that we're talking about, but that's the intensive number.
STEVE CANNANE: Greg Hunt has altered the transcript of the original Lateline interview and posted it on his website to reflect what he says was his intended definition of 100 square kilometres.
Based on this altered figure, Greg Hunt believes 150 million tonnes of carbon dioxide can be abated in one year over one million hectares.
But using the CSIRO's best estimate, you'd need a land mass of at least 75 million hectares to do this. And if you take the CSIRO's figures at the lower end of the scale, then you'd need 500 million hectares, or 65 per cent of the land mass of Australia.
But Greg Hunt questions the CSIRO figures.
GREG HUNT: Well there is a debate, and what we're seeing is that people such as Christine Jones, probably the pre-eminent soil carbon scientist in Australia and one of the world's leading soil carbon scientists, has a very different view. Her view is that Australia can capture an extraordinary part of its overall emissions, far greater than we've proposed. We've been very conservative in our estimates of what Australia as a whole through incentives to farmers could absorb.
STEVE CANNANE: The CSIRO does not take into consideration the field work of Dr Christine Jones because it's yet to be peer reviewed.
Peter Cosier says the Coalition is being irresponsible with their target.
PETER COSIER: We're very much in favour of soil carbon, but I think it's irresponsible to set a carbon reduction target based on information which is not sufficient to give you that target. So I think they're creating false expectations, I think farmers will be very reluctant to enter that market even if it did happen, and when they do, I don't think you'll achieve the volumes that have been promised in the Coalition's policy.
STEVE CANNANE: Steve Cannane, Lateline.
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