Reductions or removals? Why science — not just market forces — must shape our pathway to net zero

2050: It’s the deadline that scientists have given us to achieve net-zero global CO2 emissions if we’re to limit global warming to 1.5˚C and mitigate the worst-case scenario impacts of climate change on human and environmental health. Growing public awareness around the need to reach net-zero emissions has sparked a firestorm of corporate commitments. In the last year alone, the number of companies pledging to achieve net-zero emissions by 2050 has increased threefold, from 500 at the end of 2019 to 1,541.

With net zero now positioned as the new standard for climate action, there is more pressure on companies than ever before to ramp up climate action. To turn this ambition into actions that will keep us on track to hit net zero by 2050, we need a common, science-based definition of what this goal means for businesses and how they can get there. This means understanding the science behind CO2 reductions and COremovals.

Science of sustainability Net Zero Absolute zero carbon removal

To reach net zero by 2050, we need a common, science-based definition of what the goal means for business and clarity on how companies can apply the concept. This means understanding the science behind CO2 reductions and CO2 removals.

Net zero as North Star: but where are we headed?

The rapid uptake of corporate net-zero targets is a welcomed sight as we near the end of the first year in what the International Panel on Climate Change (IPCC) has dubbed the decade of action. But once we start to scratch beneath the surface and take a closer look at what targets and claims actually entail for action, some serious discrepancies start to emerge — the level of ambition and climate impact varies considerably. With no general consensus on what net zero means for industry, businesses are left to interpret the goal themselves with market forces at play. As a result, the goal is being interpreted in very different ways — some of which could cause us to lose steam on our trek towards transformation, making it impossible to reach net zero in time. 

Companies demonstrating real commitment to the goal develop targets and invest in strategies that allow them to maximize their potential contribution to the fight on climate change. This includes significant emissions reductions across the value chain and shifting business models to align with a net-zero economy. This approach requires a profound shift away from business as usual

Beyond reductions, using CO2 removals — for instance, tree planting — to reach the net zero threshold is a common strategy. This raises a few red flags for long-term business success and for climate. Although greenhouse gas removals are an important component of an effective global net-zero strategy, they will not take us to 1.5°C on their own. 

So why are removals gathering so much momentum? Many companies want to be perceived as being part of the solution, as creating benefits rather than producing impacts. The higher the removals, the more likely we can continue business and society as usual. And who can argue against planting trees and fostering healthy soil? However, many companies and consumers don’t understand the science behind accounting for potentially reversible removals

When companies make the claim that they are net-zero or their products are net-zero while continuing to emit fossil CO2 emissions as normal, this sends a false message to the general public that they are contributing to global carbon neutrality as defined through the science presented by the IPCC. Carbon removals can be seen as a “silver bullet,” a simple solution to a complex problem. Oversimplification and decontextualization of the climate science that underpins them, paired with a lack of scientific oversight, further bolsters this idea. This can lead to ineffective action, greenwashing and unintended environmental impacts.

(Mis)Understanding the science of removals

As a market-driven society, our instinct is to seek out market-based solutions to address climate change.  But we need to proceed with caution, grounded in a solid understanding of the science and a systems-level view.

The intention of carbon removal markets is ultimately an admirable one: to compel businesses to address their operations’ and supply chains’ contribution to climate change. In practice, however, they are often built on a simplistic and flawed understanding of net zero, namely that 1 tonne of CO2 drawn down and stored in tree stands or soils neutralizes 1 tonne of fossil CO2 emissions. This type of accounting confuses two discrete concepts in sustainability science: inventory and impact. 

Inventory in the case of greenhouse gas (GHG) accounting is the flow of greenhouse gases in and out of a system. For example, the flow of CO2 from the atmosphere into agricultural soils can be inventoried for a farming system. Impact, in this case climate impact, refers to the potential of a greenhouse gas flow to lead to global temperature change. In many cases,  inventory is being mistaken for impact, particularly in relation to carbon removals.

When CO2 is removed from the atmosphere, this is an inventory flow. To evaluate the impact of removal on climate, we need to consider the  amount of time it is removed for. International consensus on GHG accounting as outlined by the IPCC recommends a 100-year time frame to consider the effect a GHG inventory flow in a given year may have on climate.

Following the IPCC 100-year time horizon for global warming potential, and choosing a pragmatic modelling approach means that 1 tonne of CO2 sequestered in a tree today would need to stay stored over the next 100 years in order to neutralize 1 tonne of fossil CO2 emitted today. Put simply, carbon needs to be taken out of the atmosphere for 100 years for it to be considered a complete negative emission. Accounting an inventory of carbon removed from the atmosphere in one year or over several years to neutralize an emission is essentially assuming this storage is permanent. Biogenic storage (carbon sequestered in soils and trees), however, can be reversed by changes in land use management, or by events such as fires or floods. 

In order to return CO2 balance to pre-industrial levels, removals, in theory, would need to sequester more carbon than has been released  by anthropogenic dismantling of natural systems through deforestation and land-use change AND all of the fossil carbon that has been emitted. That’s a tall order. 

It’s for this very reason that the IPCC has stressed the need to prioritize deep reductions in CO2 emissions (41-58% by 2030 and 91-95% by 2050) as well as reductions in methane (CH4) and nitrous oxide (N2O) emissions. It’s the most feasible way to ensure that we will be able to cap the global rise in temperature to 1.5°C and avoid reliance on future large-scale deployment of carbon dioxide removal. Surpassing the 1.5°C threshold will result in irreversible damage to food and water security, infrastructure, ecosystems, and human health. This is why some organizations are suggesting that companies should not be able to make carbon neutral or net-zero claims, as they should be referring to a global state of CO2 balance — not the state of a single company. 

Why scientific oversight matters: lessons learned from biofuels

Biofuels offer a cautionary tale of what can happen when a market-based solution oversimplifies and decontextualizes impacts on climate and focuses on inventory flow.

For the last two decades, biofuels (made from maize, palm, sugarcane and other plant-based feedstocks) have been promoted in some markets as a sustainable alternative to fossil fuels. Initially, they were seen as a promising solution to shift away from fossil fuels. It was assumed that biofuels would not increase atmospheric concentrations of GHG, the reason being that when biofuels are burned, the CO2 they release through combustion was recently in the atmosphere and only just taken up by a plant through photosynthesis, as opposed to fossil fuels, which contain carbon sequestered by plants millions of years ago. That is why releasing CO2 from biofuels is usually considered as a neutral climate impact.

On a molecular level, it makes sense. From a systems-level view, however, the wider implications of biofuels — land-use change and deforestation, which release CO2 into the atmosphere and reduce sequestration potential — come into focus. Now in 2020, the European Union has developed a framework to phase out biofuels from crops that pose risks for land-use change by 2030 after witnessing over the years how the biofuels market has led to land conversions and deforestation. 

We’re starting to see a similar situation arise with the rapid expansion of carbon markets focused on the benefits of removals. Largely unregulated, they are emphasizing investments in sequestering carbon in trees and soils. To date, there are no strict rules to define what proportion of a company’s emissions can be neutralized through removals. Is it a quarter? Half? All? Should companies even be allowed to make claims of neutrality? The lack of clarity, and the flexibility in how companies apply the concept, is making many carbon-neutral claims meaningless. 

Getting net zero right

We can and we must do better. Here’s how:

1+ Establish a standardized,  science-based understanding of the role of removals towards achieving net zero for industry.

A robust definition of what net zero means for business and how they can get there is critical if net-zero targets are going to drive real transformation and live up to their promise.

There are several recent activities towards this goal, including the Science Based Targets initiative’s publication of a paper on setting science-basednet-zero targets in the corporate sector and the release of Carbone 4 and Net Zero Initiative’s framework on carbon neutrality. The former suggests a net-zero concept can be applied to companies with reduction as priority, whereas the latter suggests companies can only work towards collective, global goals but cannot claim neutrality or net zero.

The right accounting rules need to be in place to ensure that working towards the carbon neutral or net-zero goal translates to collective good, and not just for the public image or marketing of a product or company.

2+ Account for carbon removals as climate impact and not as inventory.

Remember, the flow of a greenhouse gas may be inventoried for a given year, but the impact on climate is the contribution to global temperature rise over a given time horizon — 100 years according to international consensus. In simple terms, this means that CO2 needs to be removed from the atmosphere for at least 100 years to completely neutralize a fossil CO2 emission in a given year.  

3+ Think beyond carbon and look for win-wins.

Some solutions for carbon reduction and removal can offer benefits for other planetary boundaries as well. Trees are critical for promoting pollination and biodiversity and preventing soil erosion. Healthy soils also promote biodiversity by providing a physically and chemically complex habitat for the diverse organisms that help regulate vital soil services. What’s more healthy soils are critical for maintaining productivity and product quality, and reducing reliance on excessive chemical inputs that contribute to the transgression of planetary boundaries for nitrogen and phosphorus cycles.

Quantis is in the process of convening stakeholders and working with our clients around these important points to ensure that both reduction pathways and CO2 removals are being considered in a way that is aligned with the science and drives business transformation. Will you join us?

Looking to leverage environmental science for smarter decision-making?
Talk to Alexi.

Alexi Ernstoff
Global Science Lead
Quantis

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