Has NZ peaked already?
At the COP27 summit, countries are mulling a promise to ensure carbon emissions peak in 2025. But would the pledge be any more than greenwash, asks Olivia Wannan.
Climate summit negotiators are tossing around a promise: to hit peak global emissions by 2025. A peak would be a significant milestone, since climate pollution has stubbornly risen year after year.
Experts warn this peak must come ‘‘before 2025 at the latest’’ for a shot at limiting global warming to 1.5C – thus reducing the chances of much worse climate damage.
However, some global energy boffins now expect carbon emissions to peak in 2025 anyway, meaning a promise could be little more than greenwash.
Negotiators from 197 countries have gathered for an annual summit, known as COP27.
New Zealand’s lead climate ambassador, Kay Harrison, said an agreement for ‘‘global peaking’’ of emissions by 2025 was a conversation topic at events leading up to COP.
‘‘That’s not something that’s in the Paris Agreement or in the rulebook, but there is a suggestion from what the science has been telling us that this is something we could galvanise around and act on,’’ she told stakeholders at a briefing last month.
A Ministry of Foreign Affairs and Trade spokesperson confirmed some countries ‘‘are pushing to build on’’ previous summits and ensure global efforts are ‘‘grounded in [the] best available science’’.
The world is already 1.1C warmer than the pre-fossil-fuel era, and this has caused more severe and deadly floods and heatwaves.
Climate scientists have warned that heating above 1.5C could turbocharge the impacts. For this reason, COP leaders are aiming to keep heating inside 1.5C.
Earlier this year, the Intergovernmental Panel on Climate Change (IPCC), a global expert body, recalculated greenhouse gas trajectories and stressed that carbon dioxide emissions must ‘‘peak before 2025 at the latest and be reduced by 43% by 2030’’ for the world to have a decent shot at 1.5C.
(It also said methane would need to fall ‘‘by about a third’’.)
Paul Winton, the founder of the 1point5 project, said aiming to peak by 2025 would reflect ‘‘the edge of the science’’. All paths compatible with 1.5C peaked between 2020 and 2025, he added. ‘‘It’s the end of the end of the end.’’
Carbon emissions must fall sharply after a peak to stay under 2C, Winton said. ‘‘It’s really what happens after that that matters. It’s how steep we go down.’’
Have New Zealand emissions peaked? ‘‘We don’t know that yet.
In the last couple of years with very messy data, it’s hard to infer . . . We haven’t yet seen any substantive emissions reduction programmes kick in. Some of the ones that have been put in place – that are great – are soft.’’
However, Winton thought a ‘‘global peak’’ commitment could act as a focal point.
‘‘It’s easy to visualise,’’ he said. ‘‘If we say we should have peaked in 2020, then everyone becomes dismayed and we do nothing.
‘‘I think there’s some really important messaging around hope and the possibility of change.’’
In the lead-up to COP27, the International Energy Agency (IEA) found carbon dioxide emissions are likely to peak soon.
Economies are moving away from coal, oil and gas, after renewable energy became cheaper. Following Russia’s invasion of Ukraine, fossil fuels are more expensive and – for countries that import them – less politically appealing. Countries including the United States have passed major clean energy laws.
Current policies globally will cause carbon emissions to peak in 2025, the IEA found. If governments introduce new policies to meet the green promises they’ve already announced, emissions could peak sooner.
However, the speed at which carbon emissions drop following the peak is also critical, as the IEA report highlights.
Governments’ current policies would only cause carbon to drift down after 2025, whereas the IEA estimated emissions would need to fall 40% by the end of the decade to put the world on track to reach net-zero by 2050, and achieve 1.5C.
The United Nations Environment Programme came to a different conclusion. It expects global emissions to rise until 2030, unless governments introduce new carbon-cutting policies.
The UN body announced before COP27 that there was ‘‘no credible pathway’’ to 1.5C. However, if governments manage to meet all their net-zero targets and other green commitments, the world could hold warming to 1.8C, it concluded.
‘‘If we say we should have peaked in 2020, then everyone becomes dismayed and we do nothing. I think there’s some really important messaging around hope and the possibility of change.’’
Paul Winton
Founder of the 1point5 project