Are “net-zero” climate targets just hot air?

More than 130 countries have set or are considering net-zero emissions goals, and many are stepping up as they prepare for next week’s COP26 climate meeting in Glasgow, Scotland. The United States, New Zealand, Costa Rica, Japan, and Argentina all aim to achieve net-zero emissions by 2050. The European Union aims to be “climate-neutral,” another way of framing net-zero. Even Russia and Saudi Arabia (the world’s top oil exporter) now have net-zero emissions targets.

Private companies are getting into the game, too. At least 20 percent of the 2,000 largest companies have set net-zero emissions targets, including giants like Apple, Ford, and Microsoft.

But “net-zero” is different from zero emissions, and this nebulous term can obscure a lot of important differences in how countries and companies actually plan to limit their contributions to climate change.

There are no standards that govern what activities actually count as net-zero. “The ‘net’ is always there in front of the ‘zero,’ but the ‘net’ part is a bit vague, especially with country-level commitments,” Derik Broekhoff, a senior scientist at the Stockholm Environment Institute, told Vox.

When a country aims for net-zero emissions — as opposed to simply zero emissions — it’s essentially promising to balance out its climate pollution, so that overall, it doesn’t harm the global climate.

For example, if a factory owner can’t figure out how to eliminate their emissions with current technologies, they can pay to restore a mangrove swamp that will absorb an equivalent amount of carbon dioxide. If the mangrove absorbs roughly what the factory pollutes, the factory theoretically won’t contribute to warming. (The idea of net-zero sometimes goes beyond carbon dioxide and accounts for other heat-trapping gases, like methane.)

In principle, the idea of net-zero offers countries and companies flexibility in meeting climate goals. But in practice, critics say that net-zero pledges delay meaningful reductions in greenhouse gases and provide cover to those unwilling to take immediate steps to limit emissions.

“On the road to COP26, corporations are using ‘net-zero’ to block effective climate policy and greenwash their image while maintaining business-as-usual,” according to a report from the nonprofit group Corporate Accountability.

A giant sand artwork seen in May across New Brighton Beach in Wirral, England, highlighting the COP26 global climate conference that begins October 31, 2021. The artwork, by British artists Sand in Your Eye, asks world leaders to commit to net-zero carbon dioxide emissions by 2050.

Christopher Furlong/Getty Images

Not all net-zero commitments are equal. So the question is: How seriously should we take a given net-zero target? And how do we separate the good ones from the bad ones? If bad net-zero targets take root, they could shield the worst emitters from scrutiny and allow greenhouse gases to continue to rise, even as the window for averting climate catastrophe slams shut.

What makes a good net-zero emissions target

To stop the planet from warming further, all of humanity will need to achieve a version of net-zero emissions. Any greenhouse gases that are released into the atmosphere will need to be sucked out again, whether by trees, microorganisms, or carbon-scrubbing machines.

That’s because carbon dioxide, the main human-produced greenhouse gas, can linger in the atmosphere for centuries. Even if CO2 emissions slow to a trickle, they will still accumulate and continue warming the planet, albeit at a slower rate.

The Paris climate agreement, for instance, set a goal for limiting warming this century to less than 2 degrees Celsius, with a more optimistic goalpost of staying below 1.5°C (compared to global average temperatures before the industrial revolution). Reaching either of these objectives would require humanity to eliminate its greenhouse gas emissions, but on different timelines. The longer it takes, the worse the warming.

In the context of climate change, the atmosphere doesn’t care where the emissions are coming from or where they go, just the overall quantity that makes it into the sky. So in theory, matching greenhouse gas outputs with withdrawals can eliminate impacts on the climate.

However, it takes a lot of work to truly counter the damage of emissions. “I think just saying, ‘I’m going to be net-zero,’ with no concrete plans to achieve that goal, is not legitimate,” said Kelley Kizzier, vice president for global climate at the Environmental Defense Fund. “We have to understand what that company or country is going to do to make that a reality.”

Here are questions to ask about net-zero commitments.

Is the country or company making actual reductions in emissions?

There is no substitute for reducing overall emissions. Preventing greenhouse gases from spewing into the sky in the first place is the most meaningful and straightforward way to curb humanity’s impact on the climate. That means phasing out fossil fuels like oil and gas as completely as possible, as quickly as possible.

This also has positive effects beyond mitigating climate change. A smokestack can pollute its neighborhood and make people sick, even if a forest is counteracting its CO2 emissions, for example. Compared to net emissions reductions, “The marginal benefits of [total] emissions reductions and avoided emissions are far higher,” according to Broekhoff.

Another concern is that there are only so many options out there for balancing emissions. If too many companies and governments try to buy their way to net-zero emissions without making their own reductions, there won’t be enough carbon-absorbing tactics to go around. The largest burden of reducing emissions may then end up falling on the people with the fewest means to do so.

A strong net-zero emissions plan should therefore have large and immediate reductions in absolute emissions at its core.

Are they setting interim targets?

Many countries and companies have set their net-zero finish line in 2050. That’s less than 30 years away — 2050 is closer to us than 1990. And meeting the 1.5°C goal of the Paris agreement requires action on an even shorter time frame. Hitting this target would require halving global emissions as soon as 2030, the Intergovernmental Panel on Climate Change reported in 2018.

That’s why emissions reductions have to begin now. A credible net-zero plan should have concrete benchmarks between now and the middle of the century. Milestones also provide opportunities for observers like citizens and investors to gauge progress and hold institutions accountable. For instance, in April, the US set a goal of cutting 42 percent of its current greenhouse gas emissions by 2030.

How much money is being invested, and where?

There are few better ways to show you’re serious than by spending money. How much a business or government is willing to spend on reducing emissions and the clean-energy transition reflects the strength of their commitment.

But where that money is spent matters too. Deploying zero-emissions energy to displace fossil fuels, capturing leaking methane, and phasing out hydrofluorocarbons yield immense climate benefits over the near term. Funding research and development could lead to breakthroughs that mitigate climate change over decades.

Paying to offset emissions could yield climate benefits too, but if that’s the only pillar of a net-zero plan, it could just end up as a way for wealthy corporations and countries to buy their way out of their climate obligations.

Are the offsets measurable and lasting?

The transition to clean energy isn’t going to happen overnight. It’s also going to be more difficult for some places, like developing countries that need cheap fuel and remote regions with few renewable energy options.

Even for countries and companies that can aggressively ratchet down their emissions, the last mile of greenhouse-gas production may prove especially difficult to eliminate. That includes activities like steel, cement, and chemicals manufacturing. Sectors like international aviation are particularly difficult to decarbonize because cleaner alternatives are not yet available on large scales.

“We know that all emissions won’t be driven to zero, and we need to address those emissions through removals,” said Kizzier.

In these instances, countries and companies will have little choice but to pay others to reduce emissions on their behalf. This is the most contentious aspect of net-zero. There are a lot of ways to compensate for emissions, but some have serious drawbacks. Restoring forests that have been degraded is one popular mechanism. As trees and vegetation grow, they can take in vast quantities of carbon dioxide from the air, but the accounting has proven tricky. Many of these projects have failed to deliver the promised reductions and some have even backfired, leading to more emissions.

There are other strategies to balance out emissions. An emitter can finance clean energy sources and use them to drive coal, oil, and natural gas off the market, zeroing out their own emissions. They can also install carbon capture and storage systems on fossil-fuel power plants. There are even companies building machines that can suck carbon dioxide straight out of the air. Of course, many of these measures are expensive, technologically immature, and could run into the same accounting issues as nature-based offsets.

Pods with tech to store carbon dioxide removed from the air deep underground are shown in Hellisheidi, Iceland, on September 7, 2021. Startups Climeworks AG and Carbfix are pitching the tech as a way to potentially reverse some of the damage of CO2 emissions.

Arnaldur Halldorsson/Bloomberg via Getty Images

Despite these challenges, some experts say it is possible to create viable offsets with proper measurement and verification. And given the amount that humans have already polluted, it may soon be necessary not just to zero out human impacts on the climate but to achieve net negative emissions — that is, withdraw more CO2 from the air than goes in.

Every scenario for stabilizing the global climate around 1.5°C of warming involves net-negative emissions after the middle of the century, the IPCC reported in 2018. Its low-end estimate was that humanity would have to withdraw 100 gigatons of carbon dioxide from the air by 2100, roughly double the amount that humanity produces in a year today. The high-end estimate was 1,000 gigatons.

So the work needed to limit climate change won’t end in 2050 and can’t stop at net-zero.

Will net-zero pledges build a more just future?

The US is the world’s largest cumulative emitter of greenhouse gases and currently the second-largest emitter, behind China and ahead of India.

Many of the countries that have historically emitted the most greenhouse gases have become some of the world’s wealthiest. Yet the countries that have historically emitted the least greenhouse gases, like island countries, stand to suffer the most from climate change.

A national net-zero target should therefore be evaluated on how well it addresses this discrepancy. “You could easily argue that the wealthy countries of the global north and companies operating in those countries should go well beyond net-zero to effectively net negative emissions,” said Broekhoff. “They need to reduce their emissions as much as possible, and they need to help the rest of the world get to net-zero.” And many environmental activists argue that 2050 is too late as a target.

Wealthier countries also have to ensure that they don’t hinder vital activities like food production or development in other countries. And again, offsets have to complement overall emissions reductions, not substitute them. Otherwise, rich nations and corporations could simply pay others to fulfill their obligations to reduce emissions.

Many net-zero climate targets have a dirty loophole: exports

The net-zero plans that countries are putting out ahead of the COP26 meeting provide an opportunity to test out these principles. At this meeting, countries are expected to come to the negotiating table with stronger climate change commitments than they presented when the Paris agreement was assembled in 2015.

But many of the newer commitments are inward-looking, focused solely on emissions within national borders and ignoring their exports of fossil fuels.

Australia, for example, published a proposal for achieving net-zero emissions by 2050 that relies heavily on investments in low-emissions technologies. But its interim target for 2030 hasn’t budged. And while Australia’s government expects domestic greenhouse gas emissions to fall, it remains the world’s third-largest fossil fuel exporter and will continue selling coal and natural gas abroad. “Australia’s coal and gas export industries will continue through to 2050 and beyond, supporting jobs and regional communities,” according to the plan.

Similarly, Saudi Arabia is aiming for net-zero emissions by 2060 and is investing $186 billion in cutting its emissions, but it expects to continue exporting oil in the meantime. Even the US has urged countries like Saudi Arabia to boost oil production to stimulate the global economy.

Norway, which is aiming to cut its domestic emissions by 55 percent by 2030, is also aiming to expand its oil and gas industry. As long as these countries are extracting fossil fuels and inviting other countries to burn them, they’ll never be able to credibly claim that they are having zero impact on the global climate. In fact, they’re profiting from this destruction.

While countries are only taking responsibility for the emissions within their borders, mitigating climate change requires looking beyond them. Getting these countries to reduce exports of dirty fuels looms as one of the biggest challenges of the upcoming climate talks.

Despite all the caveats and drawbacks, net-zero targets could still benefit the global climate. It will be hard to make progress without them. But these promises, and the steps countries and companies take to try to fulfill them, deserve intense scrutiny to ensure that they deliver.