Solomon Morris Makau checks the fallen tree for snakes before he wraps a tape measure around the trunk. The early morning sun is overwhelming in the dryland forests of the Kasigau corridor, which separates the east and west Tsavo national parks in southern Kenya. Two guards keep watch for elephants and lions. There is little sign of green among the sprawling acacias, which stand silently in their punishing wait for the end of the dry season. Despite the threat from puff adders, Makau and his team have a job to do: measure the trees and shrubs in this 50 sq metre area to calculate their growth and change in carbon stock.

“This one is lying dead,” says Makau, of one of the trees pushed over by elephants – but tens of thousands around it are still alive, stretching out in the distance as far as the eye can see.

Solomon Morris Makau, right, leads a team of environmental technicians in gathering bio data from natural vegetation

Just two years ago, the survival of these trees –** a crucial elephant habitat **– was the basis of a multibillion dollar carbon boom that touched almost every large-scale forest on Earth, underpinning the environmental claims of some of the biggest companies in the world. Netflix and Shell were among the companies that bought millions of credits from Kasigau. The market reached more than $2bn (£1.5bn), propelled by a wave of enthusiasm for offsets as a solution to global heating and biodiversity loss. Each credit represented a tonne of CO2 that was not released into the atmosphere from deforestation, theoretically cancelling out emissions from flying, fashion, food and fossil fuels. During the pandemic, leading investment banks formed trading desks for offsets as prices surged from a few dollars to more than $30 a credit for some schemes.

But today, a large part of the money and enthusiasm for these schemes has dried up after a dramatic market collapse. Crucial flaws in the way credits were calculated indicated that the overwhelming majority of forest protection credits approved by Verra, the world’s leading certifier, massively overstated their impact.

Agnes Kipee says payments to villages from the project have stopped

In 2023, a joint Guardian investigation found that, based on analysis of a significant percentage of the projects, more than 90% of offsets did not represent genuine carbon reductions, according to independent research published by journals including Science, PNAS and Conservation Biology. Another paper, published in Science last month, reinforced the finding that there were deep flaws in the Verra system, and another is expected in the coming months. The Washington-based NGO says two of the previous studies have been “discredited” and declined to comment on the latest Science study. Fragility in the market compounded after the re-election of Donald Trump, as banks and big businesses began rolling back their green commitments.

The market downturn wiped hundreds of millions off the market – and along with it, the funding for a number of projects that actually were successfully slowing deforestation – including the handful that were stopping large amounts of forest loss.

“The rumour in the community is that the project is dying because there is no money coming in,” says Agnes Kipee, 60, who lives in a village inside the Kasigau project boundaries. “Before, we were getting a lot of stipends from the carbon project. Right now, nothing is coming. We wonder what is happening,” she says.

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From the air, there is little doubt that the Kasigau carbon project – the first approved under Verra’s system – is helping to keep these dryland forests standing. It is likely less than the project itself claimed, according to analysis by the carbon credit rating agency BeZero, which the project operator Wildlife Works disputes. But there is a sharp line between the mass of trees inside the scheme, home to hundreds of elephants, giraffes, buffalo and other wildlife, and the expanse of scrub beyond it, where charcoal burners and subsistence agriculture have devoured the forest.

Achieving that is far more difficult than it sounds.** **Globally, the world has so far failed to protect forests, which are crucial for regulating temperature and rainfall. World leaders pledged to end deforestation by 2030 at Cop26 in Glasgow, but four years later, the rate of loss is largely unchanged. Swathes of the Amazon, the Congo basin and rainforests in east Asia continue to disappear each year.

“It sounds so simple. But it is super difficult to stop deforestation,” says Julia Jones, a professor in conservation science at Bangor University in Wales. “Conservationists have been trying to achieve this for a very long time. [Forests] are crucial for our planet so despite the challenges, we have no other option but to achieve this,” she says.

An aerial view of deforestation on unprotected land cleared for farming and charcoal, compared with forest on the Kasigau project land

Jones was a co-author on one of the papers that highlighted deep flaws in Verra’s forest offsets. She says that offsetting emissions by protecting forests will not help stop global heating, but insists the system has to be reformed to support successful projects.

“It is undeniable that money has been wasted on projects that have not slowed deforestation. But that doesn’t mean we should throw the baby out with the bathwater. There are really good projects out there,” says Jones.

But the collapse of the carbon market means that those projects, too, are struggling.

Over the lifetime of the scheme, $70m flowed to the communities that live in and around Kasigau, according to the project, paying for school fees, improved healthcare facilities and water storage. For the 120,000 people living in the 200,000-hectare (490,000-acre) project area, many of whom are subsistence farmers threatened by poverty, it was their share in the reward for keeping the forest standing.

This year, very little is expected to reach local people. In 2023, broader skepticism about credits was compounded in Kasigau after allegations of sexual abuse by Wildlife Works staff. Two men were fired by the US company after an investigation.

Trees are measured and data collected to calculate growth and change in carbon stock

Newton Nyiro, 50-year-old farmer and mountain guide, says reviving the project is crucial to protect Kasigau’s forests. He used to work as part of the team measuring the biomass of the trees.

“There is no income now. We are really suffering. We depend on the forest. Some families do charcoal burning. Now, they see that they can protect [the forest] and get opportunities. Because of climate change, if you cut down the trees, the rain will not come,” he says, pointing to areas in the town where trees have been cleared.

“Without the project, Kasigau would be finished. Look over there – it is not part of the project. If this project is phased out, Kasigau would not have trees. The carbon credits help.”

Newton Nyiro says families are now suffering as they have lost their income

Jo Anderson, co-founder of Carbon Tanzania, says: “Tackling deforestation demands a different approach in Tanzania. That forests are under threat and being lost is uncontroversial for the communities we work with. They experience land invasion routinely and, without carbon revenues, they have no agency to counter these forces.”

Today, Verra’s system is undergoing a dramatic overhaul. Over the past 18 months, the nonprofit has transformed the methods used to calculate credits. While some experts still have reservations, many say the new system will be much better. Project developers will no longer be allowed to perform their own carbon credit calculations and there will be more transparency about the datasets.

“It is a significant improvement. The new system cannot be gamed like it was in the past,” says Axel Michaelowa, a researcher at the University of Zurich. “Verra’s behaviour still has shortcomings. They are not a knight in shining armour. But with these kinds of credits, it has tried to reform itself and has appeared to learn its lesson,” he says.

An aerial photo of land being cleared for farming

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For many in the sector, the biggest question is whether companies will start buying offsets again if the efforts to reform are successful. In the early 2020s, Disney, easyJet and Gucci were among dozens of companies that made major carbon credits purchases as part of efforts to show they were committed to climate action, with many declaring their products had become “carbon neutral”. But in the era of Donald Trump, the atmosphere around corporate action on the climate crisis has changed dramatically.

“The green agenda is dead,” Ryanair CEO, Michael O’Leary, declared at a recent event, according to the FT. His company is among several that have scrapped the use of offsets in recent months.

With many carbon market firms making layoffs and struggling for money, some fear that efforts to reform may have come too late. Optimists point to future compliance markets, where companies could be required to buy credits to counteract their financial damage. But many suggest their fate is tied to the future of the broader environmental world.

Tommy Ricketts, co-founder of BeZero, a rating agency for carbon credits, says: “With the climate movement right now, it is hard to know if this is a low that’s going to get lower and basically disappear. Or is it actually trying to improve itself so that when the zeitgeist returns we are fit for purpose?

“Will we be able to say that we did fix these things and we are not arguing with each other any more? I don’t know, but I hope it’s the former.”

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