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IPCC report author Bronwyn Hayward says New Zealand cities can tackle transport and construction emissions themselves


By Dan Brunskill

A New Zealand author of a new climate change report says we should focus on cutting emissions at the city council level and fund farmers to transition away from dairy.

Bronwyn Hayward, a political science professor at Canterbury University, was one of 50 authors of the latest Intergovernmental Panel on Climate Change (IPCC) report.

The AR6 Synthesis Report, released Tuesday morning, summarizes the past six years of climate research and gives policymakers recommendations on how to prevent catastrophic warming.

AR6 warns the “pace and scale” of emissions reductions has been insufficient to tackle climate change and the work required to keep global warming to 1.5°C was becoming more difficult.

Hayward said NZ was lagging behind other developed countries, many of which have been more successful at reducing emissions.

"I think New Zealanders don't realize what outliers we are now. As a country we're one of the very, very few countries where emissions are still rising."

Stats NZ said gross greenhouse gas emission data between 1990 and 2020 had shown no sustained reductions compared with a reference period in 2005.

Emissions did fall in 2020 but this was largely due to covid lockdowns which significantly reduced emissions from road transport.

Combustion and concrete

Transport was still NZ’s biggest contributor to carbon dioxide emissions that year – making up 38% of total emissions – followed by manufacturing and construction at 19%.

Hayward said city governments may be able to tackle these emissions better than central governments or international groups.

“Urban areas are the site of 70% of our global emissions, so city leadership is crucial because that's where you can reduce your fossil fuel based transport and encourage different kinds of building materials”.

Auckland, Christchurch, and Wellington have very significant emissions which, if reduced, would have a big impact on emissions nationally.

“At a city level people can imagine the way in which the actions are going to actually make a significant difference to emissions reduction and also improve quality of life”.

The place to begin looking for emissions reductions are in the transport and construction sectors. This might mean building a reliable network of electric buses, or other forms of low-emission transport.

Urban planning rules could encourage new buildings to be built closer together, include green spaces, and not use large amounts of concrete — which has a poor carbon footprint.

Focusing on lowering emissions in cities could also help to deescalate the political tension between urban and rural communities, Hayward said.

However, we were “kidding ourselves” if we thought we could get away with not reducing methane emissions as well.

She said the government had to provide financial support for dairy farmers who want to transition to other types of farming that produce less methane.

“We encouraged farmers to take large debts and shift into dairy, and it was great for our economy, but we’re finding ourselves in a situation where increasingly it's going to be very hard to convince the rest of the world that we’re a fair trade partner”.

Betting the house

The AR6 Synthesis Report said policies and laws aimed at mitigating global warming had expanded, but not enough to stay below 1.5°C and possibly not 2°C.

However, it also noted it was possible to overshoot these marks and gradually cool the planet by achieving and sustaining net negative global CO2 emissions.

“This would require additional deployment of carbon dioxide removal, compared to pathways without overshoot, leading to greater feasibility and sustainability concerns,” it said.

It is a risky strategy that will come with adverse impacts and rely on the creation of much more effective carbon capture and storage technologies than we currently have.

Hayward said many governments, including our own, were unwilling to bear the costs of mitigation and were effectively gambling that future technologies will dig them out of a hole.

“It's never going to be easier or cheaper than it is now. Every increment of warming over 1.5°C we're going to have fewer and fewer options”.

AR6 said accelerating climate policies would reduce projected losses and damages, while also providing other benefits such as better air quality.

This story was originally published on and has been republished here with permission.