"It is interesting to see industrial emissions falling 5% while GDP increased 3.5%. Is this a Covid-related shift, or the start of decarbonisation?”

McLachalan, one of three experts asked to comment on yesterday’s release by the Science Media Centre, welcomed the drop in emissions from electricity generation.

“As well as the shift from coal to hydro, new wind farms began operation. 2021 saw a record level of new wind and solar projects announced so we can expect electricity emissions to continue to fall and for fossil fuel power stations to be decommissioned over the next few years.”

But he said the big picture remained unclear due to the impact of Covid.

“Annual emissions were similar to the previous year at 81 million tonnes CO2e, down on pre-Covid levels of 85 million tonnes. This is mostly due to international aviation, which Stats NZ includes where the Ministry for Environment generally does not. As no measures are in place yet to address international aviation emissions, this can be expected to bounce back post-Covid.

"Apart from lockdowns, there appear to be underlying 6% annual increases in household transport emissions. They likely have not even peaked yet, let alone begun a decline. The ground-breaking Clean Vehicles Plan is a first step to addressing these but a lot more needs to happen as well. This is an area where the Emissions Reduction Plan and the promised 'climate budget' can make a difference."

Auckland lockdown likely explanation

NIWA atmospheric scientist Dr Hinrich Shaefer believes the isolated nature of Auckland’s lockdown is likely to be the explanation for the growing gap between emissions and GDP growth.

"After the 2020 lockdown, emissions dropped but rebounded right away. Identifying which type of emissions were avoided through the lockdowns in the long run can show us effective and sustainable mitigation targets.

"Compared to 2020, this year’s emission decrease went with a lower loss of GDP, probably because the lockdown was largely restricted to the Auckland area. The primary sector and mining maintained their emissions, which are dominated by the gases methane and nitrous oxide. More fundamental and structural change will be needed for long-term greenhouse gas reductions from these industries,” he said.

"Aotearoa-New Zealand will have to continually reduce emissions at similar rates over the next decades in response to the climate crisis. Therefore, the breakdown of the current drop holds lessons how to cut greenhouse gases most efficiently, even though such lessons require further thought and research.

"The biggest emissions drop is in the infrastructure of industrial activities (energy and water supplies, waste) and is three times as large as the drop in emissions directly attributed to manufacturing. This points to big gains in long-term emissions reductions if the energy infrastructure of our industry is improved. Construction and transport are the other sectors with large reductions in emission. This shows the potential in sustainable reductions by restructuring transport and the need to move to low-emissions materials and processes in construction."

No sustained changes to economy

 

Dr Olaf Morgenstern said people shouldn’t read too much into the figures. “They don’t reflect sustained changes in our economy that would indicate that we’re on a path to carbon neutrality."

He said drops of the some order need to be repeated every year if New Zealand is to reach carbon neutrality by 2050.

“Covid-19 is an unusual, and unusually disruptive reason for these drops. We won’t want to resort to lockdowns to reach carbon neutrality. Also the reduction in coal burning at Huntley, the fossil-fuel power plant in the Waikato, may be due to relatively good hydropower generation in the South Island.”