September 17, 2019 By Kelly Levin, Taryn Fransen, Clea Schumer và Chantal Davis Cover Image by: Aaron Minnick/toludenim.com.

Editor"s Note: This article was updated in May 2021 khổng lồ include toludenim.com’s lademo research and information about new national net-zero targets.

The latest research is clear: To avoid the worst climate impacts, global greenhouse gas (GHG) emissions will need lớn drop by half by 2030 và reach net-zero around mid-century.

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Recognizing this urgency, a rapidly growing number of national government, local government & business leaders are making commitments lớn reach net-zero emissions within their jurisdictions or businesses. To date, over fifty countries have communicated such “net-zero targets,” including the world’s largest emitters (Đài Loan Trung Quốc & the United States). On top of that, hundreds more regions, cities and businesses have phối targets of their own.

These numbers are climbing quickly, particularly because the U.N. Secretary General asked countries to lớn come forward with net-zero targets. The U.N. High Level Climate Champions’ Race to Zero chiến dịch also calls on regions, cities, businesses, investors & civil society lớn submit plans khổng lồ reach net-zero emissions by 2050 in advance of the United Nations climate negotiations (COP 26) in Glasgow in November 2021.

But what does a net-zero target mean, what’s the science behind net-zero and which countries have sầu already made such commitments? Here are nine comtháng questions & answers about net zero:

1. What Does It Mean to lớn Reach Net-Zero Emissions?

Net-zero emissions will be achieved when all GHG emissions released by humans are counterbalanced by removing GHGs from the atmosphere in a process known as carbon removal.

First and foremost, human-caused emissions (such as those from fossil-fueled vehicles và factories) should be reduced as close to zero as possible. Any remaining GHGs should then be balanced with an equivalent amount of carbon removal, which can happen through things lượt thích restoring forests or using direct air capture và storage (DACS) giải pháp công nghệ. Reaching net-zero emissions is akin to achieving "climate neutrality."

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The Special Report on Global Warming of 1.5˚C, from the Intergovernmental Panel on Climate Change (IPCC), finds that if the world reaches net-zero emissions by 2040, the chance of limiting warming lớn 1.5 degrees C is considerably higher. The sooner emissions peak, & the lower they are at that point, the more realistic achieving net zero becomes. This would also create less reliance on carbon removal in the second half of the century.

This does not suggest that all countries need to lớn reach net-zero emissions at the same time. The chances of limiting warming lớn 1.5 degrees C, however, depover significantly on how soon the highest emitters reach net-zero emissions. Equity-related considerations — including responsibility for past emissions, echất lượng in per-capita emissions & capacity lớn act — also suggest earlier dates for wealthier, higher-emitting countries.

Importantly, the time frame for reaching net-zero emissions is different for CO2 alone versus for CO2 plus other GHGs like methane, nitrous oxide & fluorinated gases. For non-CO2 emissions, the net zero date is later because models suggest that some of these emissions — such as methane from agricultural sources — are more difficult to lớn phase out. However, these potent but short-lived gases will drive temperatures higher in the near-term, potentially pushing temperature change past the 1.5 degrees C threshold much earlier.

Because of this, it"s important for countries lớn specify whether their net-zero targets cover CO2 only or all GHGs. A comprehensive sầu net-zero emissions target would include all GHGs, ensuring that non-CO2 gases are also reduced.

3. What Needs khổng lồ Happen to Achieve Net-Zero Emissions?

Policy, giải pháp công nghệ and behavior need to shift across the board. For example, in pathways lớn 1.5 degrees C, renewables are projected to supply 70-85% of electricity by 2050. Energy efficiency và fuel-switching measures are critical for transportation. Improving the efficiency of food production, changing dietary choices, halting deforestation, restoring degraded lands and reducing food loss và waste also have significant potential to reduce emissions.

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In some cases, emissions are actually getting worse. Despite tremendous acceleration in renewable energy, adoption will need to increase by a factor of five sầu khổng lồ reach 2030 & 2050 goals. Current rates of renovation for both residential và commercial buildings, for instance, fall between 1% và 2% per year on average, whereas they need to lớn reach 2.5-3.5% per year by 2030. And the world needs lớn drastically slow deforestation và increase tree cover gain five times faster by 2030.

5. How Many Countries Have Net-Zero Targets?

Global momentum for setting net-zero targets is growing quickly, with key economies like Trung Quốc, the United States và the European Union articulating such commitments. Bhuchảy was the first country to lớn phối a net-zero target in năm ngoái. Now over 50 countries, representing more than half of global emissions, have sầu mix a net-zero target.


Climate Watch’s Net-Zero Tracker shows how these targets were phối, such as through nationally determined contributions (NDCs), long-term low GHG emissions development strategies (LTS), domestic laws,policies or high-màn chơi political pledges from heads of state or other cabinet members.

6. Why and How Should Countries Align Their 2030 Emissions-Reduction Targets with a Net-Zero Emissions Goal?

When beginning a journey khổng lồ reach net-zero emissions by mid-century, countries must pursue near-term action with their long-term objectives in mind. This will help avoid locking in carbon-intensive sầu, non-resilient infrastructure và technologies. Countries can also cut near- & long-term costs by investing in green infrastructure that will not need khổng lồ be phased out later, designing consistent policies and sending strong signals khổng lồ the private sector to invest in climate action.

Under the Paris Agreement, countries agreed to lớn submit climate plans every five sầu years, known as nationally determined contributions, or NDCs. NDCs are an important tool lớn align near- và long-term goals. When informed by a country’s long-term vision, these documents can help governments implement the types of policies, signals, targets and other enhancement strategies necessary in the nearer term khổng lồ realize an ambitious mid-century objective sầu.

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Many countries with net-zero targets are beginning lớn incorporate them directly into lớn their near-term NDCs. These targets are also being expressed in many countries across other law và policy documents. The most advantageous action, ultimately, will be for countries to express their net-zero commitments in as many source documents as possible, including NDCs. This will make the target as durable & binding as possible, allowing for synergistic planning.

7. Does the Paris Agreement Commit Countries lớn Achieving Net-Zero Emissions?

In short, yes. However, while the Paris Agreement establishes a global goal that implies reaching net-zero emissions, it was left unresolved when individual countries should reach that goal.

The Paris Agreement sets a long-term goal of achieving "a balance between anthropogenic emissions by sources & removals by sinks of greenhouse gases in the second half of this century, on the basis of equity, và in the context of sustainable development và efforts to eradicate poverty." This concept of balancing emissions and removals is akin to lớn reaching net-zero emissions.

The Paris Agreement also commits governments lớn putting forward plans to lớn sharply reduce emissions and ramp up efforts to lớn reach net-zero emissions. The Paris Agreement’s invitation lớn countries khổng lồ submit long-term, low-emissions development strategies by COP. 26 is one opportunity for countries lớn phối net-zero targets and chart how they alặng to make such transitions.

Ultimately, commitments to lớn create bold short- and long-term targets that align with a net-zero emissions future sover important signals to lớn all levels of government, the private sector and the public that leaders are betting on a safe và prosperous future.

8. Are Net-Zero Targets a Form of Greenwashing?

No, but they can be if used as an excuse khổng lồ not take bold climate action in the near-term.

Although net-zero targets continue lớn gain traction with governments and companies, skeptical voices have emerged, from academic journals to chiến dịch groups lớn Greta Thunberg’s speech in Davos. Critiques of net-zero targets include:

a. The “net” aspect of net-zero targets could dampen efforts to lớn rapidly cut emissions.

Critics are concerned that this could foster an overreliance on carbon dioxide removal, allowing decision-makers lớn use net-zero targets to lớn avoid emission reductions in the near-term. Decision-makers can address this concern by setting absolute reduction targets (targets that vì chưng not rely on removals) alongside their longer-term net reduction targets.

b. Some countries’ net-zero targets rely on purchasing emissions reductions, delaying reductions within their own boundaries.

Some countries are setting net-zero targets that rely on investing in or paying for emissions reductions from other countries to use toward their own targets. There’s concern that government leaders might use this strategy to avoid reducing their own emissions in the long-term. Decision-makers can address this concern by setting deep emission reduction targets that explicitly avoid or limit using offsets khổng lồ achieve sầu their goals.

c. The time horizon for net-zero targets — typically 2050 — feels distant.

Today’s infrastructure can last for decades and have sầu a major impact on mid-century targets. Decision-makers must take this inlớn tài khoản by establishing near- and mid-term milestones for their path to lớn net-zero emissions, including by setting ambitious 2030 emission reduction targets as part of their NDCs. NDCs are subject lớn transparency & accountability mechanisms under the Paris Agreement that can foster implementation in the near term, which is critical for a long-term net-zero goal to lớn be credible.

In short, net-zero commitments must be robust to lớn be effective sầu và advance climate action. Countries must take concrete steps to lớn set robust targets.

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