A new carbon credit trading deal reached in the final hours of COP29 has been criticised as a free pass for countries to slack off on efforts to reduce emissions at home.
The deal, sealed at the annual UN climate talks nearly a decade after it was first put forward, will allow countries to buy carbon credits from others to bring down their own balance sheet.
New Zealand had set its targets under the Paris Agreement on the assumption that it would be able to meet some of it through international cooperation - "so getting this up and running is really important", Compass Climate head Christina Hood said.
"It's a tool, it's neither good nor bad, but there's going to have to be a lot of scrutiny on whether the government is taking a high-ambition, high-integrity path, or just trying to do the minimum possible."
The plan had taken nine years to go through because countries determined to do it right had been holding out for a process with the right checks and balances in place, she said.
As it stood, countries would have to report yearly to the UN on their trading activities, but it was up to society and other countries to scrutinise behaviour.
Cindy Baxter, a COP veteran who has been at all but seven of the conferences, said it was in-line with the way New Zealand wanted to go about reducing its emissions.
"We're not alone, Switzerland is similar and Japan as well, but certainly New Zealand is aiming to meet by far the largest proportion of our climate target, [out of] anywhere in the OECD, through carbon trading."
The new scheme fell under Article six of the Paris Agreement, and a statement from COP29 said it was expected to reduce the cost of implementing countries' national climate plans by up to US$250 billion (NZ$428.5b) per year.
COP29 president Mukhtar Babayev said "climate change is a transnational challenge and Article six will enable transnational solutions. Because the atmosphere does not care where emissions savings are made."
But Baxter said there was not enough transparency in the scheme, and plenty of loopholes. One of the issues was ensuring projects resulting in carbon credits continued to reduce emissions after the credits were traded.
"For example, if you're trying to save some mangroves in Fiji, you give Fiji a whole bunch of money and say this is going to offset this amount of carbon, but what if those mangroves are destroyed by a drought, or a great big cyclone?"
Countries should be cutting emissions at home, she said.
"And that is something New Zealand is not very good at doing, has a really bad reputation for doing. We've either planted trees, or now we're trying to throw money at offset."
Greenpeace spokesperson Amanda Larsson said she, too, was concerned it would take the onus off big polluters to make reductions at home, calling it a "get out of jail free card".
"Ultimately, we really need to see significant cuts in climate pollution," she said. "And there's no such thing as high-integrity voluntary carbon markets, and a history of a lot of junk credits being sold."
Countries with the means to make meaningful change at home should not be relying on other countries stepping up, she said
The Green Party foreign affairs spokesperson Teanau Tuiono said there was strong potential in the proposal, but it was "imperative to ensure the framework is robust, and protects the rights of indigenous peoples at the same time as incentivising carbon sequestration".
It should be a wake-up call to change New Zealand's over-reliance on risky pine plantations and instead support permanent native afforestation, he said.
"This proposal emphasises how solving the climate crisis requires global collaboration on the most difficult issues. That requires building trust and confidence, by meeting commitments countries make to each other.
"Backing out of these by, for instance, [https://www.rnz.co.nz/news/political/519058/bill-to-resume-oil-and-gas-exploration-set-for-later-this-year
restarting oil and gas exploration directly against the wishes of our Pacific relatives], is not the way do to that."
Conference overall 'disappointing and frustrating'
Baxter said it had been "very difficult being forced to have another COP in a petro-state", where the host state did not have much to gain by making big progress.
"What that means is that there is not that impetus to bang heads together and get really strong agreement," she said.
But the blame could not be placed entirely on the leadership.
"The COP process is set up to work if governments bring their A-games, and they don't," she said.
"People should be bringing their really strong new climate targets [and] very few are doing that."
Another deal was clinched in overtime of the two-week conference, promising US$300b (NZ$514b) each year by 2035 for developing nations to tackle climate emissions.
Reuters has reported the funding's intended recipients have criticised it as "woefully insufficient".
Developed countries should be bringing money to the table to help the developing world decarbonise, Baxter said, and this sum was "nothing" compared with the amount being spent on fossil fuel subsidies globally.
Hood said the aspirational number to really make a difference was $1.3 trillion a year - and $300 billion was a starting point. "So yes, there is a huge gap there."
Indonesia wanted to shut down all of its coal-fired power stations by 2040, "and they're going to need help with that", she said.
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