Net zero pledges have grown in popularity in the last few years, but there is a worrying over-reliance on carbon removals without enough clarity on how they are used, experts have warned ahead of the COP26 UN climate summit in November.
“Net” zero targets use carbon offsets like tree-planting schemes to give nations or companies wiggle room, allowing a few emissions to remain as long as they are balanced out by removals.
But while robust net zero pledges “can play a central role in guiding the ongoing emissions reductions,” a study published earlier this year concluded that the majority of pledges made by over 4,000 nations, companies or organisations were vague on how carbon removals would be achieved.
“Of particular concern is the lack of clarity around offsetting. All entities, especially companies, need to disclose how, and to what extent, they plan to use offsets,” said the report by the Energy & Climate Intelligence Unit, a UK-based non-profit organisation.
Overreliance on removals instead of focusing on emissions cuts risks propping up unsustainable business models relying on fossil fuels, warned Gilles Dufrasne, policy officer at the NGO Carbon Market Watch.
“If you think about a fossil fuel company that has a business model that continues to rely on increased exploitation and extraction of fossil fuels … they can be using perfect carbon credits – their business model is still fundamentally unsustainable,” he said.
Campaigners have also condemned an EU decision to include carbon removals from forestry and agriculture – so-called “carbon sinks” – into the bloc’s 2030 climate target, saying this would effectively dilute the bloc’s climate objectives.
There is also concern over the quality and validity of voluntary offset schemes where companies can buy credits for one tonne of CO2 equivalent from projects that remove, reduce or avoid emissions.
However, this can be hard to calculate, particularly when it comes to land use offsets, and some schemes may include emissions that would have been removed or avoided anyway, said Dufrasne.
Currently, the supply of credits exceeds the demand, making them a cheaper and easier path for companies to show off their green credentials.
“For a lot of these entities, cutting emissions from their own activities and scaling up removals where they can all the way to net zero looks really hard, so buying an externally generated carbon offset is an attractive option,” said Steve Smith from Oxford Net Zero, which conducts research on climate neutrality.
“As we move towards net zero, climate ambition ramps up. By some estimates, demand for these voluntary offsets is expected to grow five to 10 times over the next 10 years, and maybe even 10 to 30 times up to 2050,” he added.
Up in smoke
The other concern about relying heavily on carbon offsets from natural sinks, like forests, is that they are not permanent. As climate change worsens, fires and pests become more of a threat to forests, which risks destroying carbon credits.
“There are risks with trees. Anything that’s reversible comes with risks attached to it,” warned Matthew Orman from the Sustainable Soils Alliance.
For instance, US wildfires over the summer caused the destruction of forests that are used to offset the emissions of companies like Microsoft and BP.
Despite this, forests are still considered vital for tackling climate change. They just need to be managed carefully, including choosing species that are more resilient to fires, said Ebony Holland from the International Institute for Environment and Development, an independent research organisation.
[Edited by Frédéric Simon]