The recent blunders of Tony Abbott and Julie Bishop have helped draw attention to the coalition’s own policy, which to achieve exactly the same reduction in emissions as Labor via “direct action”.

Greg Hunt, Opposition spokesman on climate action and environment explained how they are going to do it with soil carbon sequestration:

“We are talking about a land mass, if you are achieving the 150 million tonnes [of CO2 per annum], 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.”

Impressive. That’s 1.5 tonnes per square metre so you’d be laying down a half metre seam thick of coal every year. When queried about this, rather than saying that he missspoke, Hunt said he had his own definition of “100 square kilometres”:

“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.”

On his website, Hunt has posted an altered transcript of his interview, replacing “100 square kilometres” with “100 squared kilometres”:

“Not tens of thousands, but 100 squared kilometres of intensive agriculture would make an extraordinary achievement on many of the estimates.”

So “tens of thousands” of “squared kilometres” would be 20,000 km by 20,000 km, which is more than twice the land area of the entire Earth. More importantly, he still seems to be optimistic by factor of about a hundred over the estimate from CSIRO’s 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.”

Hunt is basing his policy on some unpublished research:

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.

Hat tip: Reader Tim.