We didn’t cover it much at the time, but one of the most significant events of last year was the Paris Outcome that world leaders agreed at climate talks in December. It’s a big deal. For the first time, every country on earth agreed that it was a necessity to keep global warming below 1.5 degrees Celsius. While the Outcome doesn’t bind countries to any specific level of emissions reductions, it does require them to submit plans and keep coming back to the negotiating table to agree to do more.

And it’s also a serious signal to markets and firms that long-term investments in fossil fuels will be increasingly risky. Open a coal mine at your own peril.

While New Zealand signed up to the agreement, the truth is that we haven’t taken many concrete steps to achieve our commitments. The result – unless we change – will be rapidly rising emissions:

MfE nz 2020 emissions target vs projections
Source: MfE

However, a recent report by the Parliamentary Commissioner for the Environment, Jan Wright, demonstrates why it’s in our interests to play our part in addressing global warming. The report, entitled “Preparing New Zealand for Rising Seas: Certainty and Uncertainty”, identifies 9,000 homes that will be put at risk if sea levels rise by only 0.5 metres. If sea levels rise by 3 metres – which some climate models expect to happen by the end of the century – that figure could be many times higher.

The PCE report observes that the impacts will be most acute in Dunedin – especially South Dunedin, which was essentially built by draining a swamp. Here’s a map showing which parts of the city will be underwater as a result of rising seas:


Following the release of the report, Listener science journalist Rebecca Macfie went to Dunedin to report on the impacts. Long story short, the wolf is already at the door:

“The evidence is overwhelming,” says Dunedin Mayor Dave Cull. Rising sea level is not a remote future threat for his city; it is already here. “It’s ­happening to us, and it’s happening now.”

Six months on from the midwinter floods that inundated South Dunedin, damaging more than 2000 homes and businesses with sewage-contaminated water, displacing 200-odd households and causing $30 million worth of damage and ongoing distress for many families, the implications of the dis­aster are in plain view.

Cull says Dunedin is confronting something akin to a “slow-motion earthquake” – an unfolding disaster in which extreme rainfall events such as happened in June (when 142mm fell in 24 hours in South Dunedin) will occur more often, and will conspire with gradually rising groundwater to cause much more frequent floods.

Addressing rising sea levels is an engineering, economic, and social problem. There are no great options for communities affected by them:

In a broad brush-stroke, those choices are already known. As Fitzharris outlined it in his 2010 report, they are “protect, retreat or evacuate. All have large costs.”

Wright suggests the situation facing South Dunedin could become analogous to a slowly unfolding red zone – a reference to the removal of 8000 Christchurch households from earthquake-damaged land that was deemed too costly and complex to rebuild on after the earthquakes of 2010 and 2011.

Unlike the Christchurch earthquake, rising sea levels are not a surprise. We can predict them coming a long way off – and, with the right political will, we can plan to manage the effects. But while some local communities are making plans, central government seems to have its head in the sand:

There has been no request for financial support from the Government – yet. Nor is there any pot of money available to a city like Dunedin facing certain threat from sea-level rise, although Local Government New Zealand has been pushing for the Government to set up a national fund similar to EQC that would allow property owners to be bought out before disaster strikes, rather than after.

Environment Minister Nick Smith says he doesn’t have enough information to comment on the issues facing South Dunedin, but argues any move to surrender communities or developed areas is premature. “I think based on where the science and the knowledge is at this point, to be starting to withdraw from areas would be an overreaction.” Smith knows as well as anyone that, although Dunedin is the most severely affected, it is by no means alone. Wright’s report identifies 9000 properties at certain risk of rising seas, including in the Hutt Valley, Christchurch and Napier.

Dunedin is the first to come under threat, but this is an issue that will eventually affect most New Zealand cities, as most of them are built by the coast. It’s not something that can be ignored in when building infrastructure or choosing where and how to grow.

However, the flip side is that cities can also do a lot to prevent climate change from getting worse. In New Zealand, approximately 40% of emissions come from transport, mostly from using cars to get around cities. Vehicle emissions are strongly linked to urban form – when I analysed emissions from commute journeys using Census data, I found that they increased with distance from the city centre in NZ’s major cities:

Annual CO2 emissions per commuter DRAFT v1

Technology changes may help to get our urban transport emissions under control. This is not a guaranteed win, though. Past increases in fuel efficiency haven’t done much to reduce emissions, as people have just responded by buying bigger cars. Electric cars would do the trick… but uptake of new vehicle technologies been anemic to date.

Fortunately, some things can be done right now, as the technology and techniques are currently available. This means:

  • Increasing the availability and efficiency of public transport services, which are low-emissions when well-used. Getting the CRL and the new bus network in place is important, as is rolling out bus lanes throughout the city.
  • Making it easier and safer to walk and cycle everywhere in the city. The $300 million Urban Cycleway Fund is an important step forward in this area, but it will be necessary to follow it up with more.
  • Getting pricing right. Currently, driving and parking is underpriced due to minimum parking requirements, which result in an oversupply of free parking, and a lack of congestion pricing. As a result, people drive too much, often for low-value trips.

At a national level, a well-functioning Emissions Trading Scheme, or a similar carbon tax, is essential for ensuring that people face the right prices when choosing how to invest. In other words, there’s a lot to do… but it can be done!

How do you think that New Zealand cities should address the likelihood of sea level rise?

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  1. I wouldn’t expect anything from central government until national is no longer in it.

    An EQC type fund for dealing with effects of climate change is a very good idea though. The cost of dealing with this is going to far exceed what local govt can afford.

    1. Agreed. National can’t see anything but the rear-vision mirror. They’ve always been like that…..and unfortunately, so are most of their voters. It more or less defines that part of society. It may well be that as baby boomers have aged, the tendency has grown. However, National only have a 2-3 seat majority thanks to their one-man MMP rort parties. We can’t be far from the tipping point……assuming the trend to stick heads in sand has peaked. Perhaps it hasn’t.

      I’d be in favour of a tax surcharge on people who KNOWINGLY voted for parties with policies that fail to address long term risks. The present is an excellent example: National does nothing about climate change…..South Dunedin disappears under the waves despite decades of warnings….so National voters have to pay for it.

      One of problems with democracy is that people who vote for dumb stuff – and get it – aren’t accountable for it.

        1. That’s part of what winds me up. I’ve voted against this stuff (ignoring climate change; thinking more roads and cars are the answer to everything; privatising prisons / infrastructure) every step of the way….and I’m still on the receiving end of it. 🙂

      1. Imagine if that logic was applied in the UK. All those Labour voters would be paying every cent of the GFC.

        1. So they should. Though I think we would have to allow that First Past the Post prevents a huge number of people – most often the majority (Blair’s last govt had only 35% support, IIRC) – from actually electing those they want to represent them. To that extent, it’s hard to hold anyone accountable as they weren’t free to exercise real choice sufficient for the purpose. MMP makes a huge difference. Voters can elect who they want. That simply isn’t possible for a majority of voters under FPTP. I think the present government in the UK got a LOT less than 40% of the vote.

  2. The National Party keeps going on about the 40% emissions from cows and the farming sector and saying Global Warming is just to hard to deal with; this is complete rubbish and this Government will go down in history as ignoring the biggest problem of the 21st century.
    To many people go on about the big problem of global warming without focusing on the huge benefits that it will have to the economy once things start moving.
    What the National Party is missing is that 60% of the emissions does not come from cows – such as the transport example above; plus creating more wind farms for the energy sector. There are 11 Wind farms consented in NZ but not being built. This is a huge number, as getting a consent to build a wind-farm is not easy and is expensive but there are no market signals from the Government to get them built – and again they are a quick easy environmental win.
    The UK has dropped it’s emissions from 1990 by over 20%, whereas we have risen. If a country the same size as ours with 60 million people can do it, NZ can easily do it as well.
    I would be interested to see if natural solutions such as Mangroves can be used to help our coastal cities than the use of walls and such. I don’t know much about them, but I believe they can absorb the more frequent events such as flooding quite easy – but I guess the big problem is that some people don’t like the look of mangroves and it does not meet our Victorian view on what the coast should be like

    1. Mangroves are in my view a menace. The natural habitat of wading birds and countless estuaries have been invaded by the run off from suburban housing development and water borne metals from car exhausts, due to insufficient infrastructure. If mangroves were present pre forest felling and land clearance, well fair enough, but as they started really proliferating from the 1960s its got nothing to do with Victorian views. Its nearly all down to urban spread. Maybe intensification and public transport will stop the flood.

      1. The major constraint on mangroves is frost (though they need suitable esturine environments). The number of frosts in the north of NZ is declining sharply and allowing them to increase, and the urban heat island effects of development are contributing too.

  3. Of course urban form is a huge part of the issue. Proximity trumps mobility, in other words not needing to make that trip or it being much shorter, whatever the mode, in large part defines the carbon intensity of a conurbation.

    Therefore adding more auto-dependent sprawl to Auckland is simply untenable from a Carbon Intensity perspective, even with, eventually, Electric Vehicles. It is regrettable that our wishy-washy Councillors and various hopelessly ill-informed and naive sprawl fantasists like Bogunovich and Bradbury [Whangarei-Whakatane!] blithely continue to fail to count ANY of the transport costs of endless sprawl, let alone the vast carbon fail that these out-of-time and frankly impossible visions freight.

  4. Indeed, totally on board. But it can’t possibly be enough. Most of the simulations suggest that the only possible less terrible outcome means pressing every possible lever (simulation linked by Vox.com; http://www.vox.com/2015/10/31/9649518/energy-policy-simulator).
    _Mandate_ EV, tax ICE cars harshly, promote mass transit, tax carbon, promote afforestation and discourage land clearance, promote conservation and so forth. My personal top of the list is a heavy carbon tax, but no only is it not happening, sadness, by itself it still won’t change things fast enough, 8-(.

    So. In my personal life, I travel only by mass transit. I have planted moy trees. And I can _feel_ the Koch brother’s laughing at me, cause it won’t make a difference even to NZ.

    1. This mornings lobbyists in the Herald, which is essentially what Bradbury and Bogunovich are, don’t come as a surprise and this strategy has an air of familiarity about it. The well-funded well-heeled and I severely doubt “apolitical” Auckland 2040 know how to play the opinion game. There’s clearly a lot at stake to keep the status quo.

  5. “Increasing the availability and efficiency of public transport services” – wont really make much difference. Even if the CRL was complete and Auckland’s rail network running at capacity, the vast majority of trips in NZ will still be made by car.
    If the government really wanted to cut emissions encouraging electric car use would be the more effective option. Maybe via a big carbon tax on petrol or by electric car subsidies.

    1. Currently, PT mode share in Auckland is in the 5% range. If we, say, tripled that to 15%, which is very achievable given outcomes observed overseas, it would equate to perhaps a 10% cut in the city’s transport emissions. (Warning: I have not done the sums in detail.) That seems material.

      However, I agree that we should be looking to pull all of the levers available to us, including changes to the vehicle fleet.

    2. Electric vans and light delivery trucks would also make a big difference – iirc 70% of freight movements are local trips by smaller commercial vehicles, perhaps a higher RUC for non-electric commercial vehicles might help.

  6. The large white areas shown in your maps would be better represented as very dark grey, because areas out side of the public transport network and home to commuting workers are not going to be low emission.

    1. Actually, as matters currently stand, many of those areas have relatively low commuting emissions per worker due to the higher prevalence of working from home / working on farms in rural areas. That will change as residential development spreads out further, of course.

      1. There is about 5 km thick band of countryside living all around Auckland, then in pockets out to about 40 km. They will change and become less polluting as development spreads further out.

  7. Fascinating post, Peter. Sea level rise is certainly a glaring issue for Dunedin and (to a smaller extent) many other NZ cities. Imperative to act on climate change, starting now, and with transport as a major focus for NZ.

  8. Can someone explain the CO2 map. Does that say that even in the most far away areas you only gnerate 3 tonnes of carbon a year? Am I right in thinking that at 9.50 per unit the total carbon cost each is only $28.50 per year?

    1. So my (limited) understanding of the ETS is they collect 1/2 the cost of carbon from transport so the $29 per year from the outskirts of Auckland they already collect $14.50. So the answer is collect the other $14.50 at the pump and let people live where ever the hell they choose. If these number are right then worrying about $14.50 per year is like a cup of coffee every four months.

      1. Except $9.50 / tonne wont be high enough to meet our obligations. But I agree, lets internalise the cost of carbon, road use/congestion, parking, air pollution, noise and safety of road travel and let people do what they like.

        1. I agree it won’t meet the committed reduction and nor will it do anything practical but for the sake of ticking a box we might as well charge the full amount and worry about something we can actually change. Hunger, housing, health, anything.

  9. We have to keep most of the carbon in the ground and that means no cars or trucks including battery driven, so it’s not going to happen, what government would get voted in if they proposed a tax on carbon so high or a tax on our carbon footprint that made road transport obsolete.

    How much would it cost to rebuild all the rail networks and coastal shipping we had before the car and truck took over, in those days all industry was along rail transport corridors, we would have to walk away from anywhere that couldn’t be serviced by low energy links. ie. cargo bikes would replace trucks, I can’t see that happening not while there is oil to exploit.

    Methane accounts for about half of the rise in world temperatures and something we need to take seriously, as the permafrost melts around the arctic circle we have no way of knowing if we are heading for a feedback that we can’t control, we don’t have much time to start implementing drastic reductions in our carbon footprint in all developed nations.

        1. We don’t need to dam anything. I’ve been looking around and have just discovered almost 4000 hectares of relatively flat, development-ready land within 10 kilometres of the city centre. Just needs a short bridge!

          1. Too hard (literally and figuratively) to put any pipes or electricity wires etc into that ground.

            Better to extend your bridge ’round the back to Motutapu island, easier to build on plus it hides the development behind Rangitoto from the view of all those NIMBYS out east suburbs who will fight to protect their unspoiled “views” if they even see a peep of housing anywhere they can see.

  10. Or Dave Cull could do his job and make sure essential infrastructure works are done. Like, you know, the mud tanks that hadn’t been cleaned and backed up water into streets?

  11. When you look at the carbon map of Auckland it seems proximity to the rail doesn’t seem to make any noticeable difference. Only proximity to the centre seems to matter. They could reduce carbon by intensifying housing closer in. Maybe someone should suggest it.

  12. Hi Peter your CO2 map of Christchurch shows both New Brighton and Sumner have relatively high emissions yet both suburbs were developed as tram suburbs with tramlines as early as 1896 -so pre the combustion engine era. Check out the cool map here http://www.teara.govt.nz/en/map/10370/the-expansion-of-christchurch-to-1926

    Maybe the solution is going ‘back to the future’, that is if sea level rises can be minimised and places like New Brighton and Sumner can be protected for what rises that come.

    1. That’s a really interesting map! It’s fascinating to see how early the extensions to New Brighton, Sumner, and Papanui happened. It’s a contrast with Auckland, where the early tram network was relatively compact and didn’t serve beachside suburbs.

      1. Yes -Somewhere I read -maybe at Ferrymead museum -that in the early days Sumner was a weekend playground for Christchurch. A Victorian seaside town with B&Bs, boutique hotels, baches, ice cream parlours…. before it became a commuting suburb of Christchurch. The first trams were not fast enough to make Sumner a place to live if you worked in Christchurch -but it was ok for a weekend excursion.

        I wonder if Canterbury could do the same with commuter rail to Waipara -the centre of our wine growing region (because it is protected from cold easterlies by the Teviot Hills). This being about 60km north of Christchurch -about an hour by train -so pushing the limit for commuting distance.

        But it might work as a playground for tourists and Christchurch city folk -if it got some infrastructure like a regular commuter rail service.

        Build some limestone chip bike paths to the vineyards -wine tastings -the kids can go on the historic steam train from Waipara to Waikari…….

          1. Waipara valley could be New Zealand’s version of Australia’s Barossa Valley -only better because it would anchor a triangle of tourist hotspots of Hamner Springs and Kaikoura.

  13. And it is revealed today that the government has sneakily lifted the maximum size and weight of trucks allowed on our roads. And thanks to a kiwi rail line closure, there will be more of these behemoths on the road wreaking havoc and increasing road maintenance costs.

    1. It’s not all one way traffic. This from Port of Tauranga interim report.
      “We are increasing efficiencies in the supply chain by ensuring the north and south bound trains are fully utilised. Coda (our freight and logistics partnership with Kotahi) has been making good progress in securing significant domestic freight customers to provide southbound backhaul loads to balance the northbound dairy trains from the lower North Island. Port of Tauranga is now handling more than 90% of the North Island dairy export volumes. Coda has recently commenced work on expanding its intermodal freight hub in Otahuhu to handle these increased volumes. This intermodal operation is expected to remove approximately 5,000 truck movements per year”

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