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Cambridge Centre for Carbon Credits (4C)

A Bayaka person prepares food by a fire in a forest clearing in the Central African Republic rainforest.

Why is it important to harness the power of nature-based solutions for carbon offsetting? And how can we promote forest conservation projects which respect the rights and livelihoods of people who live in forest communities?

Tom is a nature-based solutions expert, with a decade’s experience in carbon credit generation and tropical socio-ecological systems. Tom is driven to understand what works to protect forests and address the climate crisis, using his skills for remote sensing, machine learning and econometrics.

Interview by James Millerstudent environmental activist, film-maker. Text lightly edited for clarity.

(Photo credit: Wikimedia Commons JMGRACIA100, CC BY-SA-4.0)

What’s your background and how did you originate 4C?

I did my PhD in tropical ecology, working on species coexistence. I got to the end of that and thought ‘this is all a bit theoretical, I’d like to do something applied now’. So I joined the RSPB to work at the first ecosystem restoration concession in Indonesia, in this big area about the same size as Greater London. I did that for three years. There, I found that protecting forest in rapidly developing countries is really hard; the paradigm is still heavily based on trying to persuade people that conservation is a moral obligation, but I think that’s a very patronizing approach when people are struggling to meet their basic needs. While I was there my thinking changed completely—the ecology of the trees seemed irrelevant, compared with the importance of understanding socioeconomic needs of the people.

Afterwards, l moved back to the UK, and started working with David Coomes, using a variety of remote sensing approaches to measure forest condition. I could see there was something important to be done with remote sensing to understand whether conservation projects have been truly successful or not.

So, I merged those remote sensing and impact evaluation skills with my interest in the socioeconomic aspects of conservation as part of an Enterprise Tech project through the Cambridge Judge Business School. I could see the business opportunity of using smartphones to go provide an evidential base for carbon credits. Andrew Balmford then invited me to start working on evaluating carbon credits for the university, I met Srinivasan Keshav and Anil Madhavapeddy, and told them about my ideas. Anil thought it was exactly the kind of thing they could use to act as the basis for collaboration between the Computer Lab and the Conservation Research Institute. So we pitched the idea to the Tezos Foundation, and brought in the funding.

And that’s how I ended up here!

A lot of people these days seem to dismiss offsets and nature based solutions as a bit of a distraction from the real hard work of cutting down on emissions. Why is it important that we don't dismiss the benefits of nature-based solutions but harness them?

I think the short answer is you have to do both. We're fully aware that we need to completely decarbonize our economy as fast as possible to reach net zero. What's been laid out as achievable by the IPCC, to stay below 2°C, requires cutting emissions, but the actual amount that we'll be able to cut will not allow us to meet our targets alone, that’s why we'll also have to use negative carbon technologies as well.

That is a fundamental fact.

In addition, there's a whole load of land-based emissions, which contribute more than 20% of global emissions. I think many higher income countries can reduce those as part of their net zero targets, but there are large swathes of the world that won’t do that, in my belief, unless there is a strong financial incentive. Brazil, Indonesia, and the Congo, for example, are places which are much less wealthy, and can make money out of developing land for agriculture. The IPCC target is to stop deforestation now and set a billion hectares into restoration in the next 10 years—I just don't see how we're ever going to meet those targets unless there's a really strong financial flow towards those deforestation frontiers and carbon finance is the best mechanism available to do that.

And you don't think we're going to get that without investment from the private sector, as well as governments?

Well, I think you could if there were really strong agreements that include huge transfers of wealth. But I'm highly dubious that the international community would agree in a multilateral way how those transfers of wealth would happen. There are lots of examples where governments have failed to meet the mark: Indonesia's Norway agreement, for example. There was an agreed transfer of $1 billion, for a 10-year project aiming to slow Indonesia’s deforestation, but the deal ended when the Norwegian government fell through with very little progress. On the other hand, I see a payments for services model, within the private sector, as more likely to be achieved.

What do you think are the current problems with carbon credits produced by nature-based solutions that might have led to the current mistrust and opposition from many quarters?

The short answer is it's complicated. There's a whole dialogue around companies just carrying on emitting at a business-as-usual rate, offsetting and saying that everything's OK, when what we really need to do is decarbonise. And there's some progress being made towards that—I'm encouraged by the fact that 80% of the global economy is now signed up to a net zero pathway. That cannot be achieved without substantial decarbonisation, offsets will be a small part of that.

The other reason is that the systems for quantifying offsets are out of date, and there are logical holes all over the place. If you buy most off-the-shelf carbon credits, they will not fully offset your emissions, as you might hope they would. 

A prime example is California’s carbon offsetting scheme, which has issued 29% too many carbon credits, and there are many examples that are far worse. However, although many of these projects have overestimated their climate benefit, plenty of them still have an impact—it’s just a case of getting the calculation correct. So we have spent a lot of effort thinking through how to ensure that a carbon credit absolutely fulfils its requirement to fully offset an emission.

I can see how that work will help to solve many of the trust issues. But if I were to get the most resolute, sceptical anti-offsetter to listen to your proposal, what valid criticisms could they still level against your work?

We’re not going to prevent catastrophic climate change without a step change in forest conservation and we're not going to stop deforestation unless there is a real financial flow into the system. Countries will probably be prepared to sign up to moratoria on deforestation for international goodwill and will make all the right sounds. But when push comes to shove, and they don't get enough money from carbon credits, they might jump off that train. So I believe the issue has to be resolved, and carbon credits seem the most promising opportunity at the moment. We'll see.

Am I right in thinking that you’re also working on methodologies to assess livelihoods and justice elements of projects?

Yes. The first thing to say is that the vast majority of our thinking has gone into quantifying the climate benefit because getting that right is a really big challenge. That said, there's good experience within 4C in understanding what conservation does to people—as I've said, that is part of my motivation for being involved with this. I really think we need to find ways to get more money to the people on the ground, and that without forests being financially competitive with other land uses we won’t succeed.
And of course these projects should also contribute towards social justice.

The problem with both livelihoods and justice is that they’re really challenging to evaluate. And at the moment it’s particularly difficult because usually there is some sort of third party project between the buyer and the local people. To some extent we have to trust what the project is doing, because getting the primary measurements about material outcomes for people on the ground can be impossible. But we’re looking into it.

What have those methods looked like historically and what are you doing differently?

In the past we’ve done before-and-after control intervention evaluations on livelihoods as a result of REDD+ projects. They involve basically saying ‘this is a community involved in a REDD+ project, and over there is a community which is in all other ways the same but it’s not part of the project.’ And through time, evaluate whether the REDD+ project caused a change in livelihoods or other outcomes, that it was greater than what happened in the control group. So usually the way that's done is experimentally, but there are huge costs and ethical issues involved in doing that.

What we’re doing now is essentially similar to how we're assessing carbon. We identify a synthetic control, a counterfactual. So you say that these villages are essentially equivalent to these other villages, and ask what is the total additional economic value of the carbon project. That's based upon benefit transfers, job creation, money spent on infrastructure, etc. net of the profit from whatever economic activity would have taken place in the absence of the project. We can do that through counterfactual reasoning—we can say this area would have been 100 hectares of cocoa, but instead, it's 100 hectares of forest. And then we can say, well, what would be the financial value through time of cocoa versus financial value through time of the income from the carbon credits? The thing we ultimately want to know about livelihoods is—has that farmer become wealthier as a result of that decision or not? Of course, there are other ways of measuring livelihoods but this is the approach we are taking for now. 

Surely that is a very difficult thing to understand?

Yes. That number is always going to be quite rough and ready because the actual take home that a particular person receives is going to depend on a few different things. Not least, the fact that over a large landscape, it’s difficult to know who that money accrues to. The other detail is that we use simplifications, like approximations of what margin a farmer would receive, while in reality it's more complicated than that. During a conversion event, you might have several years, before harvests begin, where the farmer earns nothing from agriculture. And of course there are costs for maintenance, fertiliser, transport etc. So we just use a standard estimate of a transition from a certain land use to another, and the typical value per unit area. It's not perfect, but it’s a considerable step forward compared to what is available at the moment.

We have this motto: not letting perfect be the enemy of the good. The key is that we make a good step forward with what can be done today and have our eye down the road for what is better next.

And what is down the road for livelihoods? It strikes me that it must be very difficult to progress beyond anything more sophisticated than that without dedicating infeasible amounts of resources to every project.

Really, to streamline it, you need a way to remotely track wealth. There are some ways of doing this, for example the Relative Wealth Index, developed by Josh Blumenstock and colleagues takes advantage of predictive models developed on digital communications information. You can find out the frequency of telecommunication, or the density of communications towers and information within those services, even breaking it down into things like proportion of IOS versus Android devices. And that all turns out to be a really effective predictor of wealth. The challenge going forward will be how you turn that into a dynamic system that can say reliably ‘these people are getting wealthier’.

What is your vision for 4C and what kind of scale of impacts do you hope it might have?

Let's take it back to what I was saying earlier. I would love it if individuals were in the position to make decisions about whether they conserve the forest they have in their back garden or turn it into a farm, without the need for third-party intermediaries. To have a system in place where someone who wants to buy a hectare of forest conservation for a certain amount of time can do it directly with the supplier. A bit like a kind of microfinance for microconservation. That would be my dream. 

It’s a way off, but if we can help channel appropriate amounts of money to the people who need it, I think we'll make a real difference to forest conservation and climate change.