New Zealand's new environment watchdog has called to end what he says has been a "stop-go, on-again, off-again" approach to tackling climate change – and backs calls for a new major commission.

In his first report as Parliamentary Commissioner for the Environment, Simon Upton has put his support behind a new UK-style independent "Climate Commission" that would track our carbon-slashing efforts and ensure we made good on promised action.

The Government has announced it would pursue setting up such a body along with a new Zero Carbon Act, both of which aimed to set New Zealand on a path for a net-zero emissions economy by 2050.

Under the UK system, carbon budgets, enacted by Parliament, acted as stepping stones to clearly defined targets and were set about 15 years in advance to provide investors, businesses and individuals with a predictable future emissions pathway.

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Achieving that feat in New Zealand wouldn't be straightforward - but Upton saw no reason why it couldn't be done.

Upton set out his nine recommendations, including setting effective carbon budgets, establishing a credible commission, and ensuring that words are turned into deeds.

It also underlined the importance of addressing climate adaptation.

Upton believed setting separate targets for the different greenhouse gases was an option that should be considered by the new commission, but stressed the question of targets should not be confused with policy measures – such as the Emissions Trading Scheme (ETS) – imposed to reach them.

Upton also argued that an act based on the UK Climate Change Act should be designed to put in place a process for meeting carbon budgets and targets.

That would require the Government to spell out the policy measures and settings it will adopt to meet those budgets.

Further, he argued greenhouse gases from agriculture – methane and nitrous oxide, which made up about half of New Zealand's emissions profile – could not be allowed to continue rising.

"Over the seven years that I led the environment programme at the OECD, one of the questions most frequently asked by countries wrestling with climate policy was: which country has devised the best way of making progress?" Upton said.

"While there was no shortage of good ideas to choose from, the UK's approach stood out as being the one that was most likely to lock-in a stable, long-term path to lower emissions."

Upton's new report, which builds upon earlier work by predecessor Dr Jan Wright, investigated how the UK system she called for can be adapted and refined to best suit our own country.

"Of course there are differences between the UK and New Zealand, but provided they are accounted for at the outset, there is no reason this system cannot be made to work here as well."

Upton said New Zealand was playing catch-up on climate change, which made the Government's proposed legislation is timely.

"Internationally, there is a growing momentum to deal with climate change in a structured way that provides certainty for businesses and investors – it is high time New Zealand took the same approach," he said.

"We have to break out of the stop-go, on-again, off-again approach to tackling such a pressing long-term problem."

Acting Climate Change Minister Julie Anne Genter said the report offered "interesting areas for consideration".

"At the same time, Mr Upton acknowledges New Zealand has very different emissions profiles to the UK and very different challenges."

Environmental Defence Society (EDS) chairman Gary Taylor said getting cross-party agreement – as Upton stressed in the report – was crucial, given the long-term nature of the climate challenge and the need for a consistent approach across many years.

"It is what happened in the UK and why that model has durability."

Taylor said the EDS also considered a new commission a "keystone entity" for a transition to a zero-carbon future.

"The potentially more difficult question concerns how it should operate and where the respective responsibilities of the Government and commission should lie."

But Taylor said his organisation was underwhelmed by what it considered an "open-ended attitude" by Upton toward adaptation.

"He agrees there's a need for a national strategy but not sure who should do it.

"Given New Zealand's vulnerability to the effects of climate change – increased floods, droughts, storm surges and other extreme weather events – we think that a national strategy is enormously important and should rest firmly with the proposed commission.

"The alternative of leaving it to an existing government agency is not attractive.

"We need an expert entity to prepare a strategy and if the commission is properly configured, that's where responsibility should lie."

Greenpeace's Russel Norman argued that for the commission to be truly effective, it must also have the power to influence the price of carbon by changing the settings of the ETS.

"Currently the suggestion is that the commission will advise the Government if it is not meeting the milestones needed to reach net zero carbon by 2050, and the Government will then have a window of opportunity to provide a response," Norman said.

"But for this commission to actually reduce New Zealand's emissions, we need it to be more than just talk and have some teeth.

"The Reserve Bank has the power to alter the official cash rate and require minimum deposits on housing loans to counter inflation and threats to fiscal stability.

"The Climate Commission should be able to act on the greatest threat to humanity - climate change - by adjusting the price of carbon."

Associate Professor Ivan Diaz-Rainey, co-director of the University of Otago's Energy Research Centre, was concerned New Zealand didn't have the same level of cross-party commitment to tackling climate change that the UK did.

"As the report notes, there has been a reluctance to implement policies that 'bite' in New Zealand – this is true of National with their rural electorate, but also true of Labour to date," Diaz-Rainey said.

"This means that in New Zealand there is a risk that this legislation might be repealed or watered down by future administrations."

Diaz-Rainey also pointed to the report's noting that New Zealand was unlikely to be able to implement three carbon budgets in quick succession that yielded "easy" emissions reductions.

"I think here you can substitute the 'able' with 'willing' – there are plenty of ways New Zealand with a highly inefficient car fleet, land use policies that have encouraged intensification, large potential for afforestation and a housing stock that has poor levels of insulation, not to mention schools that have coal boilers, could cut emission 'easily' but not painlessly with the appropriate policies."

He added a Zero Carbon Act and an independent Climate Commission would tell us where cuts might come from and when, they didn't tell us how we were going to get there.

"So it is important work, and it is needed, but it should not be an excuse to stand still any longer - ultimately it is the policies that count."

Canterbury University political scientist Associate Professor Bronwyn Hayward, who served as a lead author on the IPCC report on restricting warming to 1.5C, believed an act and commission would need to cover changing international commitments and domestic climate impacts.

The work needed to be enabled quickly, she said, noting how some lobby groups had caused "decades of delay" to progress on climate change.

"This new Government has a once-in-a-generation opportunity and a clear mandate and now needs to set out a timetable for action and implement it."

New Zealand has pledged under the Paris Agreement to slash its emissions by 30 per cent below 2005 levels and 11 per cent below 1990 levels.