New Zealand has committed to a higher emissions reduction target for the post-2020 period ahead of crucial climate talks in December.

Minister for Climate Change Issues Tim Groser confirmed that the new target would be to reduce greenhouse gas emissions by 30 per cent from 2005 levels by 2030.

He described it as a "significant increase" on the 2020 target, which was a reduction of 5 per cent below 1990 levels.

If the new target was set to a 1990 baseline, it was the equivalent of an 11 per cent reduction.


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"While New Zealand's emissions are small on a global scale, we are keen to make a fair and ambitious contribution to the international effort to reduce greenhouse gas emissions and avoid the most harmful effects of climate change," Mr Groser said in a statement.

Emissions targets which were set under the Kyoto agreement were due to expire in 2020. All countries were now expected to set new targets for the period after 2020 as part of a climate change agreement to be concluded in Paris.

Labour and Greens wanted Government to match the EU by setting a target of at least a 40 per cent reduction on 1990 levels by 2030.

Mr Groser said Government had to ensure the target was achievable and avoided imposing unfair costs on any particular sector or group of people.

He said there were fewer opportunities for New Zealand to immediately reduce its emissions because roughly half of its pollution came from producing food "for which there aren't yet cost-effective technologies to reduce emissions".

He remained optimistic because investment in agricultural research was "beginning to bear fruit" and the cost of electric cars and hybrids was starting to fall.

"I think in 5-10 years we'll be in a good position to reduce our emissions in both agriculture and transport," he said.

New Zealand has established the Global Research Alliance to investigate how to reduce the natural emissions produced by sheep and cows.

Before setting the target, Government consulted with 1700 people in meetings across the country and received more than 15,000 written submissions.

Some criticised the rushed consultation period and the background data provided to submitters, which placed emphasis on the increased costs of a more ambitious target but provided fewer details about the costs of not combatting climate change.

Mr Groser said the 2005 baseline for the new target aligned with other significant players including the US and Canada.

The target was provisional until a new international agreement was ratified. Any rules or guidelines for achieving the target would be set after this date.

"The Government will adopt an appropriate mix of policies to ensure the target is met," the minister said.

Green Party climate spokesman Kennedy Graham said the target was "paltry" and meant New Zealand was not pulling its weight internationally on climate change.

Other countries would have to pick up New Zealand's slack, "or we'll get runaway climate change", he said. If all countries followed New Zealand's lead, catastrophic climate change would be the result.

"New Zealand can do so much better," Dr Graham said.

"National is missing this opportunity to implement policies that are good for people and the climate. We have no choice but to transition to a low-carbon economy, but National will increase the cost of this transition by delaying."

Labour's environment spokeswoman Megan Woods said the new target would make it "all but impossible" for National to meet its existing long-term goal of a 50 per cent cut in emissions by 2050.

"We can set all the targets we like, but the simple fact is that this is meaningless unless we actually meet them," she said.

"The Government has missed an opportunity. We need credible targets and a credible plan to reach them. Today, National has shown it has neither."

The main policy tool for reducing emissions, the Emissions Trading Scheme, would be reviewed this year.