Zero net emissions by 2050 — preferably sooner

By Gareth Renowden 01/03/2011

I’ve just sent my submission on the NZ government’s intention to make a formal commitment to a target of a 50 percent reduction in net greenhouse gas emissions by 2050 to the Ministry of the Environment — barely squeaking in before the published deadline. My original intention was to submit a closely argued case for a more aggressive target, but recent events militated against that. I settled for something a little more pithy, with an offer to back up my points with an oral submission if necessary. I’d also like to credit Bryan, whose incisive post on the recent “Beyond “dangerous” climate change” paper by Anderson & Bows makes a compelling case for a revision in the international received wisdom on acceptable targets. Full text below the fold…

I wish to oppose the gazetting of a target for a 50% reduction in New Zealand’s net greenhouse gas emissions by 2050, on several grounds:

  • Because it is inadequate, and fails to reflect current scientific understanding of the magnitude of the climate change problem confronting the planet.
  • Because it fails to take into account the “first mover” economic advantage in adopting low carbon policies, and because “locking in” high carbon emissions by featherbedding agriculture and protecting big emitters is a long term liability for the country and its taxpayers.
  • Because climate change is not purely a scientific or economic problem, but has moral and ethical dimensions that have intergenerational implications.
  • Because the risk of doing too little is far greater than doing too much.
  • Because the target is badly out of line with indicated targets from other advanced economies.
  • Because New Zealand’s emissions profile, coupled with our unique mix of energy resources, gives us an opportunity to position ourselves at the forefront of countries taking action on climate change, thus enhancing our “clean & green” image and ensuring a sustainable future for all our businesses. A target recognised as weak — as “50 by 50″ surely will be — will compromise that future.

I would support the gazetting of a 2050 emissions target that takes into account the reality of the situation that confronts us. That means zero net emissions at a bare minimum — preferably resulting from a strategic pathway to net negative emissions as soon as is feasible.

Should the minister wish to hear oral submissions, I would be delighted to make one by telephone or video conference.


I refer the Minister to this recent paper: Beyond ‘dangerous’ climate change: emission scenarios for a new world, Kevin Anderson and Alice Bows, Phil. Trans. R. Soc. A 2011 369, 20-44 doi: 10.1098/rsta.2010.0290 (available free here), in particular this section of the abstract:

The analysis suggests that despite high-level statements to the contrary, there is now little to no chance of maintaining the global mean surface temperature at or below 2ºC. Moreover, the impacts associated with 2ºC have been revised upwards, sufficiently so that 2ºC now more appropriately represents the threshold between ‘dangerous’ and ‘extremely dangerous’ climate change.

The Anderson & Bows analysis is worth reading in full. It reinforces the view that current international thinking on targets is badly out of line with what science is now telling us. To adopt an intentionally low target in the face of the evidence amounts to gross dereliction of duty. Not, perhaps, a legacy this government should aspire to.

A comfortable assumption that we can “live with” 2ºC is no longer warranted. To achieve any kind of long term climate stability, we will have to move beyond cutting emissions to removing carbon from the atmosphere. A nation that assumes it can continue carbon emissions in the long term — as implied in the framing of a “50 by 50″ target — is making a profound strategic mistake. To maintain a planet with ice at both poles means trying to limit atmospheric CO2 to 350 ppm or less (Hansen et al, Target Atmospheric CO2: Where Should Humanity Aim? 2008). We are currently at 390 ppm and rising rapidly.

At some time in the near future, economic prudence is going to be trumped by the necessities of survival — as some of us in Canterbury have recently discovered. I am heartened to discover the government agrees, and would wish that it apply the same thinking to our long term survival and not just tectonic misfortune.