Wellington has become the latest city to declare a climate emergency.

Photo: RNZ / Charlotte Cook

The declaration was adopted at a meeting of the Wellington City Council this morning. Only one city councillor voted against the declaration.

The room was overflowing, with people lined up with signs to hear the councillors debate the declaration.

Wellington mayor Justin Lester said the world was in peril and there was much more work to do.

Councillors have also been considering a new strategy to make the city carbon neutral by 2050.

Climate change activist Ella Magnusson, 14, said she skipped school to make her plea for change in person.

"Of my waking hours, my life feels like 40 percent school and homework, 10 percent sports, and 50 percent climate change activism and if I have to stay up until midnight to achieve this well, that's what I have to do," she said.

"If I can do this in my spare time, surely you guys can do this in your job."

Photo: RNZ / Charlotte Cook

Generation Zero representative Arlo Heynes told councillors they needed to act fast once they made the declaration.

"When the house is burning, you don't spend your time trying to design a new extinguisher, you get out," he said.

Council strategy committee chair Iona Pannett identified herself as a climate change campaigner and said scientists were "the heroes of this story, they have done the painstaking work to raise the alarm for us to take action".

Mayor Justin Lester said he accepted the evidence the world was in peril, and there was still more work to do - including making sure the council had a plan to follow through with the emergency declaration.

Nicola Young was the only councillor who voted against the declaration, and while she admitted the climate was changing she dismissed the policy as "virtue signalling" which would achieve nothing and just waste ratepayers' money.

"It would be easy to vote for this, it would give me a nice quiet life, but that is not why I am on council," she said.

"The 'first to zero' policy will achieve nothing except make the councillors feel good."

Photo: RNZ / Charlotte Cook

Ms Young described the declaration as "greenwashing" and "pious preaching".

"The council needs to stick to it's core role, making sure the gutters are clear."

Five other New Zealand councils, including Auckland and Nelson, as well as hundreds of others around the world have already declared climate emergencies.

Critics say in many cases those councils are not doing anything more than they have already been doing.

Daily podcast The Detail looks into whether declaring a climate change emergency will actually help.