Log In

Reset Password

Targets achievable, action necessary


Our columnist today is not the only one questioning the Climate Change Commission's claim that the “transformational and lasting change across society and the economy” it is calling for would cost less than 1 percent of annual GDP.

A coalition of over a dozen business and industry groups wrote to the commission's chairman Rodd Carr last week calling for the “release of crucial modelling data”, and National MPs challenged the commission on this issue yesterday.

But your editor digresses, as today's column mostly bypasses real-world debate — with the quote marks around “warming” a pointer.

To say our emissions are low on a global scale ignores the fact we will be acting along with the rest of the world, and that our emissions are high on a per-capita basis . . . principally because methane emitted by livestock on our farms accounts for 35 percent of New Zealand's greenhouse gas emissions. Through enteric fermentation in their digestion process, ruminant animals convert carbon in grass into this much more powerful (but shorter-lived) greenhouse gas. Their urine also produces a potent long-lived gas, nitrous oxide.

New Zealand could store enough energy to be 100 percent renewable, that's why a pumped hydro scheme is being investigated; or gas-fired peaking stations could be used until other storage options are available. Heavy-duty electric trucks will soon shift from demonstration vehicles to commercial production.

Most farmers would support such moves, as removing transport emissions dials back the reduction in livestock emissions we need to meet our climate commitments.

Regarding soils in forests, Scion's Dr Michelle Harnett says they are in good health, including the healthy range for acidity, and generally better than soils used for farming or growing food. However, the commission actually warns that relying too much on carbon offsets from forestry would delay action and lead to higher cumulative emissions.

On agriculture, the commission says methane reduction targets can be met purely through existing farm management practices and the (proven) use of selective breeding for low-emissions sheep; and there is scope to overachieve through new technologies like methane vaccines or inhibitors or selective breeding for low-emissions cattle.

It also should be pointed out that the commission's cost estimates do not take account of the costs of not acting, in terms of worse climate change impacts and greater reliance on carbon offsets.

See today's column

  1. Neil Henderson says:

    New Zealand’s livestock emissions only make up the stated 35% of the total through the chosen metric of comparison, the GWP 100. Professor Miles Allen of Oxford University has described it as not fit for purpose. This is before we even consider the margin of error estimate in the Greenhouse Gas Inventory that the 35% has a margin of error of plus or minus 55%. How can anyone come up with credible policy in the light of this?

    It is not the emissions that matter in curtailing global warming, but what warming any emissions may cause. Professor Allen’s research has come up with the GWP* metric. This shows that we only need to reduce livestock emissions by 10% to be warming neutral. Yet the Climate Commission has not even considered this.

    It is time we saw some scientific integrity in this discussion, not IPCC politics.

    Also in talking about electric vehicles, we need to remember that the components of electric batteries are rare and many of the known resources are in pristine areas. What is the environmental impact of mining these? Google ‘Planet of the Humans’ to find an interesting documentary to learn more. Further, trucks travel long distances in a day. How big a battery will they need to save multiple stops of several hours a piece? How many tonnes will that battery weigh? How big (or small) will their payload be?