Planting trees is not a “silver bullet” for tackling climate change, experts have said.
Tree-planting campaigns are a popular initiative for governments and businesses drawing up plans to reach net zero carbon emissions.
One campaign aims to plant a trillion trees in order to help absorb carbon dioxide from the atmosphere.
But experts said at an event hosted by London Climate Week on Monday that planting trees in the future was not a substitute for reducing emissions.
Richard Black, a climate expert and honorary research fellow at Imperial College London, told the conference that strategies relying on tree-planting were not serious.
“If an entity is basically saying, 'I’m not going to reduce my emissions but I’m going to plant enough trees to absorb them', that’s not a serious net zero target,” he said.
“The science is abundantly clear … planting trees is not a silver bullet. You’ve got to have big reductions in your own emissions.
“Then perhaps if there’s a bit that needs to be mopped up at the end, we can use nature-based solutions for some of that.”
Britain is urging countries to adopt ambitious climate targets before the Cop26 climate summit in November.
The UK’s is aiming for net zero by 2050 and a 78 per cent reduction in emissions by 2030 when compared to 1990 levels.
Britain’s Environment Ministry last month described tree-planting as a “central pillar” of its efforts towards net zero.
Nigel Topping, who is the UK’s official climate champion for Cop26, said the world could not rely on cancelling out its emissions in the future.
“It can’t just be 2050 on someone else’s watch when I’ve retired. It’s got to be a short-term target,” he said.
“It can’t rely on offsets instead of reducing emissions … and it has to be transparent so that entities can be held accountable.”
'Burn now, pay later'
Mr Black called for a distinction between what he called “good, bad and ugly” climate targets.
Net zero plans needed to have interim targets and envisage immediate action in order to fall into the “good” category, he said.
James Dyke, an assistant director of the Global Systems Institute at the University of Exeter, went further by describing net zero plans as a “dangerous trap”.
He said the slogan gave rise to a “burn now, pay later” approach in which continued emissions were hidden behind promises of future action.
“What net zero is actually allowing us to do is continue with the same destructive increase in energy and material consumption,” he said.
“We instead are inventing fantasies of future technological salvation.”
The Paris Agreement signed in 2015 calls for efforts to limit global warming to 1.5°C above pre-industrial levels.
Voicing pessimism about the target, Mr Dyke said it would only be possible with short-term cuts in emissions.
He said the economic rebound from the pandemic was likely to lead to a bumper increase in carbon emissions in 2021.
Tzeporah Berman, a professor of environmental studies at the University of York, said the world needed to get “beyond zero”.
“What’s really critical for this discussion is that companies and countries are held to account for getting to zero,” she said.
“That means short-term targets, it doesn’t just mean what the modelling says by 2050. What are your plans for 2030? What are your plans for this year?
“One of the big dangers in the net zero conversation is that it’s being used to justify the expansion of fossil fuel production. We need to stop expanding fossil fuels.”