File pic Photo: RNZ / Rebekah Parsons-King
The government is expected to reveal its next climate change target on Thursday night, amid scrutiny from the international community.
A former climate change ambassador is making the case for a 66 percent cut to the country's emissions, while a former climate change commissioner and climate scientist says the targets matter even more if the US is not involved in global efforts.
All countries have until February to reveal their targets for reducing planet heating emissions from 2031 to 2035.
Under the Paris Agreement, countries get to decide their contributions themselves, but have agreed to aim for the "highest possible ambition".
Each target has to be bigger than the last one from that country.
Professor James Renwick Photo: Supplied
New Zealand's current target is shrinking greenhouse gases by 50 percent from 2005 levels, during the decade from 2021 to 2030.
With five years left to run on those first targets, countries are now being asked for their second commitments - this time for a shorter period of five years.
While the first round of commitments has averted the worst 'hot house' scenarios for the planet, highly dangerous heating is still likely without deeper cuts to carbon dioxide and other heat-trapping gases such as methane, according to scientific analyses.
Professor James Renwick, a recent climate change commissioner, said if countries let global warming exceed 2degC, that would be "catastrophic" for global society.
"We would lock in metres of sea-level rise, redrawing the map of the world for thousands of years into the future. We would bring about massive losses in food production through heat waves, droughts and storms, and would displace hundreds of millions of people, bringing about humanitarian crises the like of which the world has never seen," he said.
Higher expectations now
Former climate change ambassador Kay Harrison - until recently New Zealand's lead climate representative in global negations - has previously said the next target needed to start with a 6, "at least," to meet the requirements of the Paris Agreement.
Today she said after reviewing the latest analysis, 66 percent would be more in line with what international partners expected from New Zealand, though there was no guarantee the country's trading partners would consider even that a reasonable goal.
"Minus 66 would be consistent with the trajectory we've already set ourselves," she said. "I wouldn't go so far as to say that would be a fair share in global terms... but I think it would probably be credible."
Harrison watched the formulation of New Zealand's 2021-2030 target from her role as a climate change diplomat.
She said expectations were higher now than they were when the current target was set.
"More recently, at the [climate summit] in Dubai in 2023, all countries there, including New Zealand, represented by Minister Simon Watts, agreed that based on the science there needed to be very, very deep reductions in emissions to keep us safe, or at least safer than we would otherwise be," she said.
"It was [agreed] to cut emissions globally by 60 percent by 2035, and of course that's a global average, and not all countries are in a position to cut their emissions by as much as 60 percent," Harrison said.
"Richer developed countries agreed to take the lead, and that is in part about capacity but it is also about historical responsibility."
Of the handful of countries that have already announced their 2031-2035 targets, Brazil - a developing country - announced 59-67 percent cuts, Switzerland 65 percent cuts, the UK promised 81 and the US, pre-President Trump's re-election, was aiming for 61-66 percent reductions. The US now plans to withdraw from the Paris Accord.
In December, all countries had to report on how they were doing at meeting their first targets.
New Zealand lodged a statement but did not include an explanation of how it would fill an estimated 84 million tonne shortfall in its first target.
Previous governments, both National and Labour-led, planned to pay for carbon reductions in other countries as a lower-cost, easier option to making all the emissions reductions at home.
However, the current government has been shy of publicly committing to making any offshore purchases in the manner of countries such as Switzerland and Singapore, despite Watts confirming the target could not be met without overseas cooperation.
"The fact that it is not mentioned in the transparency report is a big question," Harrison said.
High levels of renewable electricity and emissions coming from agriculture are factors in setting the country's target, an expert says. Photo: 123RF
"Right back in 2015 when we set our first target, we actually set it on the condition that we could use overseas credits if we needed to, to meet our target because we recognised back then that our high levels of renewable electricity and our large proportion of emissions coming from agriculture meant it might not be in our best interests to make all our contributions at home," she said.
"Yes, we needed to change our economy and yes we needed to reduce emission at home, but to make up the kind of volume [required] we were going to need to support other countries to reduce their emissions," she said.
"It was actually a condition of us going into Paris... using forestry to sequester carbon, and also buying emission reductions... we've said that consistently all the way through."
Harrison said any target bigger than the current one was also going to need international purchases, "to reduce the economic burden of a reasonable contribution to make".
New Zealand's current target was increased from 30 to 50 percent in 2021, under pressure from the international community.
But Harrison said it wasn't a big step up in effort.
"In my opinion the 2015 target, which was criticised by a lot of New Zealanders as not being ambitious enough, was actually really ambitious because we didn't have the Zero Carbon Act, we didn't have emissions budgets, we didn't have a Climate Change Commission, we didn't have emission reduction plans," she said.
"It looked like a really really huge mountain to climb, and that was a reduction of 30 percent.
"By the time we got to Glasgow, in 2021, when the UK government was hosting the [world climate summit] and the science reports said that when you add up everyone's [targets] it's not nearly enough, we were put under pressure, as everyone was, to increase our ambition and at that stage the government increased our target to to minus 50 per cent."
"But we'd already done better than we thought we were going to do back in 2015, so it wasn't that much of a step up. The number was bigger, sure, but the kind of effort we were going to have to put in was actually less," she said.
"The circumstances by 2021 were better because we'd started moving."
Harrison said if the government went with something like a 66 percent target, it would require a similar effort as before.
"I would say this isn't any more heavy lifting than it is for any other country. We can't expect developing countries to take on way more than is bearable for them when they are much poorer and haven't contributed to this problem in the way we have.
"Ambition is about, does this scare you when you look ahead at what you've committed to?
"I remember the faces of the PM and ministers in 2015 when they decided, and they were anxious about what they were committing future governments to. I remember one of them saying we will never be criticised for doing too much."
Professor Renwick said commitments matters more now the US was not involved and "all other countries have to work harder, to make up the difference. The globe must reach zero emissions of greenhouse gases, especially carbon dioxide, as soon as possible, to avoid unmanageable consequences".
"It is unfortunate that the US has signalled it will pull out of the Paris Agreement, as the US currently emits about 11 percent of the global total. Still, other countries can and must take the lead, if the US does not want to be at the forefront of this vital effort."
