20 Jan 2021

Why we can't plant our way out of climate change

From Afternoons with Jesse Mulligan, 1:37 pm on 20 January 2021

New Zealand needs to do more than plant trees to be effectively fighting climate change.

So, says Newsroom senior political reporter, Marc Daalder.

He's told Jesse Mulligan that offsetting carbon emissions by planting trees is no substitute for reducing emissions in the first place.

Carbon emissions have not yet peaked in many countries the report says.

Carbon emissions have not yet peaked in many countries the report says. Photo: AFP

In the short term, tree planting is beneficial, he says.

“The general theory is correct, if you plant a tree it does soak up carbon for a while, the main problem is that eventually it stops soaking up carbon and then you have to leave that tree there or, if you cut it down, continue re-planting that tree there, meaning that land is locked up in forest for a long time, but isn’t actually sequestering any more carbon than did the first time planted the tree.”

Offsetting is attractive because it’s easier than changing behaviour, he says.

“It’s much easier to plant trees than it is to change our societal reliance on cars and trucks for transport, fossil fuels for electricity generation and mostly cows for dairy and meat.

“It is much easier to offset emissions than it is to actually reduce them.”

In the next ten years we need to drastically reduce emissions to avoid going over about 1.5 degrees of warming above pre-industrial levels, Daalder says.

And while planting a lot of trees now might help us reach that short-term target, it doesn’t help with the long-term problem.

“Every tonne of carbon dioxide that we emit, is cumulative and will stay in the atmosphere for hundreds or thousands of years.”

So why not just start changing our behaviour now, he says.

He supports planting trees for broader environmental reasons.

“We’d like to see more native forests, we’d like to see more native birds. None of this is about not planting trees, it’s just saying planting trees can’t be our only climate change policy.”

The biggest low hanging fruit for New Zealand to slash its emissions is transport, he says.

“We know exactly how to reduce our transport emissions; it’s by turning our fossil fuel cars into electric cars and it’s by driving less overall and instead walking more, cycling more taking public transport more or working from home.

“That’s something we can do right now, that’s our low hanging fruit.”

Whether that happens depends on the political ambition of the Government, he says, but expects the Climate Change Commission which is due to report on 1 February to ramp up the pressure.

It will be a major landmark in New Zealand’s reckoning with climate change, he says – not least because it will come from an expert panel.

“The Climate Change Commission will make clear what we need to do in the next 15 years - and the next ten and the next five- is radically change the way we live our lives.”

The Government can choose not to accept that advice, but having an expert panel coming out and saying it is different, he says, to hearing advice from Greenpeace or Forest and Bird.

Many New Zealanders are under the impression we are performing well on carbon emissions, he says.

“They would probably be surprised to learn that among the 42 industrialised nations that signed the UN framework on climate change we have had the second highest increase in emissions since 1990.”

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