The Scientist Warning Against ‘Science-Based’ Targets

Tackling climate change is a complex puzzle. Hitting internationally agreed upon targets to limit warming requires the world to reduce multiple types of greenhouse gases from a multiplicity of sources on diverse timelines and across varying levels of responsibility and control by individual, corporate, and state actors. It’s no surprise the catchphrase “net zero by 2050” has taken off.

Various initiatives have sprung up to distill this complexity for businesses and governments who want to do (or say they are doing) what the “science says” is necessary. The nonprofit Science Based Targets initiative, for example, develops standard roadmaps for companies to follow to act “in line with climate science.” The groups also vets corporate plans and deems them to either be “science based” or not. Though entirely voluntary, SBTi’s approval has become a nearly mandatory mark of credibility. The group has validated the plans of more than 5,500 companies with more than $46 trillion in market capitalization — nearly half of the global economy.

But in a commentary published in the journal Nature last week, a group of Intergovernmental Panel on Climate Change experts argue that SBTi and other supposedly “science based” target-setting efforts misconstrue the science and are laden with value judgments. By striving to create straightforward, universal rules, they flatten more nuanced considerations of which emissions must be reduced, by whom and by when.

“We are arguing that those companies and countries that are best resourced, have the highest capacity to act, and have the highest responsibility for historical emissions, probably need to go a lot further than the global average,” Andy Reisinger, the lead author of the piece, told me.

In response to the paper, SBTi told me it “welcomes debate,” and that “robust debate is essential to accelerate corporate ambition and climate action.” The group is currently in the process of reviewing its Net-Zero Standard and remains “committed to refining our approaches to ensure they are effective in helping corporates to drive the urgent emissions reductions needed to combat the climate crisis.”

The commentary comes as SBTi’s reputation is already on shaky ground. In April, its board appeared to go rogue and said that the group would loosen its standards for the use of carbon offsets. The announcement was met first with surprise and later with fierce protest from the nonprofit’s staff and technical council, who had not been consulted. Environmental groups accused SBTi of taking the “science” out of its targets. The board later walked back its statement, saying that no change had been made to the rules, yet.

But interestingly enough, the new Nature commentary argues that SBTi’s board was actually on the right track. I spoke to Reisinger about this, and some of the other ways he thinks science based targets “miss the mark.”

Reisinger, who’s from New Zealand, was the vice-chair of the United Nations Intergovernmental Panel on Climate Change’s mega-report on climate mitigation from 2022. I caught him just as he had arrived in Sofia, Bulgaria, for a plenary that will determine the timeline for the next big batch of UN science reports. Our conversation has been edited for length and clarity.

Was there something in particular that inspired you to write this? Or were you just noticing the same issues over and over again?

There were probably several things. One is a confusion that’s quite prevalent between net zero CO2 emissions and net zero greenhouse gas emissions. The IPCC makes clear that to limit warming at any level, you need to reach net zero CO2 emissions, because it’s a long lived greenhouse gas and the warming effect accumulates in the atmosphere over time. You need deep reductions of shorter lived greenhouse gases like methane, but they don’t necessarily have to reach zero. And yet, a lot of people claim that the IPCC tells us that we have to reach net zero greenhouse gas emissions by 2050, which is simply not the case.

Of course, you can claim that there’s nothing wrong, surely, with going to net zero greenhouse gas emissions because that’s more ambitious. But there’s two problems with that. One is, if you want to use science, you have to get the science correct. You can’t just make it up and still claim to be science-based. Secondly, it creates a very uneven playing field between those who mainly have CO2 emissions and those who have non-CO2 emissions as a significant part of their emissions portfolio — which often are much harder to reduce.

Can you give an example of what you mean by that?

You can rapidly decarbonize and actually approach close to zero emissions in your energy generation, if that’s your dominant source of emissions. There are viable solutions to generate energy with very low or no emissions — renewables, predominantly. Nuclear in some circumstances.

But to give you another example, in Australia, the Meat and Livestock Association, they set a net zero target, but they subsequently realized it’s much harder to achieve it because methane emissions from livestock are very, very difficult to reduce entirely. Of course you can say, we’ll no longer produce beef. But if you’re the Cattle Association, you’re not going to rapidly morph into producing a different type of meat product. And so in that case, achieving net zero is much more challenging. Of course, you can’t lean back and say, Oh, it’s too difficult for us, therefore we shouldn’t try.

I want to walk through the three main points to your argument for why science-based targets “miss the mark.” I think we’ve just covered the first. The second is that these initiatives put everyone on the same timeline and subject them to the same rules, which you say could actually slow emissions reductions in the near term. Can you explain that?

The Science Based Targets initiative in particular, but also other initiatives that provide benchmarks for companies, tend to want to limit the use of offsets, where a company finances emission reductions elsewhere and claims them to achieve their own targets. And there’s very good reasons for that, because there’s a lot of greenwashing going on. Some offsets have very low integrity.

At the same time, if you set a universal rule that all offsets are bad and unscientific, you’re making a major mistake. Offsets are a way of generating financial flows towards those with less intrinsic capacity to reduce their emissions. So by making companies focus only on their own reductions, you basically cut off financial flows that could stimulate emission reductions elsewhere or generate carbon dioxide removals. Then you’re creating a problem for later on in the future, when we desperately need more carbon dioxide removal and haven’t built up the infrastructure or the accountability systems that would allow that.

As you know, there’s a lot of controversy about this right now. There are many scientists who disagree with you and don’t want the Science Based Targets initiative to loosen its rules for using offsets. Why is there this split in the scientific community about this?

I think the issue arises when you think that net zero by 2050 is the unquestioned target. But if you challenge yourself to say, well net zero by 2050 might be entirely unambitious for you, you have to reduce your own emissions and invest in offsets to go far beyond net zero by 2050 — then you might get a different reaction to it.

I think everybody would agree that if offsets are being used instead of efforts to reduce emissions that are under a company’s direct control, and they can be reduced, then offsets are a really bad idea. And of course, low integrity offsets are always a bad idea. But the solution to the risk of low integrity cannot be to walk away from it entirely, because otherwise you’ve further reduced incentives to actually generate accountability mechanisms. So the challenge would be to drive emission reductions at the company level, and on top of that, create incentives to engage in offsets, to increase financial flows to carbon dioxide removal — both permanent and inherently non permanent — because we will need it.

My understanding is that groups like SBTi and some of these other carbon market integrity initiatives agree with what you’ve just said — even if they don’t support offsetting emissions, they do support buying carbon credits to go above and beyond emissions targets. They are already advocating for that, even if they’re not necessarily creating the incentives for it.

I mean, that’s certainly a move in the right direction. But it’s creating this artificial distinction between what the science tells you, the “science based target,” and then the voluntary effort beyond that. Whereas I think it has to become an obligation. So it’s not a distinction between, here’s what the science says, and here’s where your voluntary, generous, additional contribution to global efforts might go. It is a much more integrated package of actions.

I think we’re starting to get at the third point that your commentary makes, which is about how these so-called science-based targets are inequitable. How does that work?

There’s a rich literature on differentiating targets at the country level based on responsibility for warming, or a capacity-based approach that says, if you’re rich and we have a global problem, you have to use your wealth to help solve the global problem. Most countries don’t because the more developed you are, the more unpleasant the consequences are.

At the company level, SBTi, for example, tends to use the global or regional or sectoral average rate of reductions as the benchmark that an individual company has to follow. But not every company is average, and systems transitions follow far more complex dynamics. Some incumbents have to reduce emissions much more rapidly, or they go out of business in order to create space for innovators to come in, whose emissions might rise in the near term before they go down, but with new technologies that allow deeper reductions in the long term. Assuming a uniform rate of reduction levels out all those differences.

It’s far more challenging to translate equity into meaningful metrics at the company level. But our core argument is, just because it’s hard, that cannot mean let’s not do it. So how can we challenge companies to disclose their thinking, their justification about what is good enough?

The Science Based Targets initiative formed because previously, companies were coming up with their own interpretations of the science, and there was no easy way to assess whether these plans were legitimate. Can you really imagine a middle ground where there is still some sort of policing mechanism to say whether a given corporate target is good enough?

That’s what we try to sketch as a vision, but it certainly won’t be easy. I also want to emphasize that we’re not trying to attack SBTi in principle. It’s done a world of good. And we certainly don’t want to throw the baby out with the bathwater to just cancel the idea. It’s more to use it as a starting point. As we say in our paper, you can almost take an SBTi target as the definition of what is not sufficient if you’re a company located in the Global North or a multinational company with high access to resources — human, technology and financial.

It was a wild west before SBTi and we’re not saying let’s go back to the wild west. We’re saying the pendulum might have swung too far to a universal rule that applies to everybody, but therefore applies to nobody.

There’s one especially scathing line in this commentary. You write that these generic rules “result in a pseudo-club that inadequately challenges its self-selected members while setting prohibitive expectations for those with less than average capacity.” We’ve already talked about the second half of this statement, but what do you mean by pseudo-club?

You write a science based target as a badge of achievement, a badge of honor on your company profile, assuming that therefore you have done all that can be expected of you when it comes to climate change. Most of the companies that have adopted science based targets are located in the Global North, or operate on a multinational basis and have therefore quite similar capacity. If that’s what we’re achieving — and then there’s a large number of companies that can’t possibly, under their current capacity, set science-based targets because they simply don’t have the resources — then collectively, we will fail. Science cannot tell you whether you have done as much as you could be doing. If we let the simplistic rules dominate the conversation, then we’re not going to be as ambitious as we need to be.