By
Grace Smoot

Absolute zero/ zero emissions is one of many climate change terms used in reference to our growing climate crisis. Although it is often used in conjunction with terms such as net zero and climate neutral, absolute zero is achieved by a different mechanism. So, we had to ask: What is absolute zero/ zero emissions really, and how could achieving it help us mitigate climate change?

Absolute zero/ zero emissions refers to the complete elimination of all greenhouse gas emissions without the use of carbon offsets or removals. We are not on track to achieve absolute zero by 2050 in alignment with the Paris Agreement, but many global organizations have developed net zero plans.

Keep reading to find out all about what absolute zero/zero emissions is, how we can achieve it, why it is important to mitigate climate change, if we are on track to achieve it soon enough, how it relates to the Paris Climate Agreement, and how you can personally help to achieve absolute zero/zero emissions.

The Big Picture of Absolute Zero/ Zero Emissions

Absolute zero emissions is one of many terms used when talking about climate change-specific goals. As its name suggests, absolute zero refers to the complete elimination of all greenhouse gas emissions, a feat that will require a massive overhaul of current practices. 

What absolute zero/ zero emissions means	Absolute zero emissions refers to the complete elimination of all greenhouse gas (GHG) emissions across all scopes for all entities. The use of carbon offsets or removals is not permitted to balance out residual emissions.
How we could achieve absolute zero/ zero emissions	We could achieve absolute zero emissions by cutting our GHG emissions down to zero. This would involve ceasing the use of fossil fuels and switching to zero-carbon energy sources (e.g., nuclear power), decarbonizing various industries, reducing deforestation and food waste, and investing in clean energy and energy efficiency.
Why absolute zero/ zero emissions is important to mitigate climate change	Achieving absolute zero emissions is important to mitigate climate change because we are reducing the amount of harmful emissions entering our atmosphere that contribute to climate change.
What the current status of absolute zero/ zero emissions is	We are not currently on track to reach absolute zero or even net zero by 2050, the target date identified in the Paris Climate Agreement. GHG emissions are predicted to continue to rise despite global, growing momentum and support for the net zero movement. To date, over 140 countries have stated a net zero target, covering roughly 88% of the world’s emissions.
How absolute zero/ zero emissions relates to the Paris Climate Agreement	The Paris Climate Agreement does not explicitly commit countries to achieve absolute zero. It instead marks the beginning of a shift towards a net-zero emissions world and lays out a framework to limit temperature rise to below 2°C, preferably below 1.5°C.

What Does Absolute Zero/ Zero Emissions Mean

Absolute zero/ zero emissions refers to the complete elimination of all greenhouse gas (GHG) emissions across all scopes for all entities. 

“Absolute Zero: No GHG emissions are attributable to an actor’s activities across all scopes. Under this definition, no offsets or balancing of residual emissions with removals are used. A valid end-state target.”

University of Oxford 

Absolute zero does not permit the use of carbon offsetting or carbon removal to balance residual emissions from industries where emissions are difficult to reduce.

Achieving absolute zero emissions means reducing GHG emissions down to zero across all three scopes:

• Scope 1: Direct emissions controlled or owned by a company
• Scope 2: Indirect emissions resulting from a company’s energy usage and purchase
• Scope 3: Any remaining emissions created in the company’s value chain (not covered under Scope 1 or 2)

How Could We Achieve Absolute Zero/ Zero Emissions

Achieving absolute zero emissions will require restructuring and upgrading many of our industries including energy, transportation, and agriculture.

Drastically cutting GHG emissions across all sectors of our economy would be necessary to achieve absolute zero emissions. This includes ceasing the use of fossil fuels and switching to zero-carbon energy sources (i.e., nuclear energy), decarbonizing various industries, reducing deforestation and food waste, and investing in clean energy and energy efficiency. 

Why Is Absolute Zero/ Zero Emissions Important to Mitigate Climate Change

Achieving absolute zero emissions is important because when we stop putting GHGs into our atmosphere, we slow down the rate of global climate change. It also doesn’t rely on carbon offsets, some of which can lack additionality and permanence. 

How Is Climate Change Defined

Climate change is arguably the most severe, long-term global impact of GHG emissions. Every year, over 54 billion tons (bt) of GHGs are emitted, the majority of which is CO₂. 

“Climate change: changes in the earth’s weather, including changes in temperature, wind patterns, and rainfall, especially the increase in the temperature of the earth’s atmosphere that is caused by the increase of particular gasses, especially carbon dioxide.”

Oxford Dictionary

When GHGs enter the atmosphere, they absorb sunlight and solar radiation, trapping the heat and acting as an insulator for the planet.

Since the Industrial Revolution, Earth’s temperature has risen a little more than 1 degree Celsius (C), or 2 degrees Fahrenheit (F). Between 1880-1980 the global temperature rose by 0.07°C every 10 years. This rate has more than doubled since 1981, with a current global annual temperature rise of 0.18°C, or 0.32°F, for every 10 years. 

How Does Reaching Absolute Zero/ Zero Emissions Specifically Help Mitigate Climate Change

If we achieve absolute zero we will stop emitting GHG into our atmosphere, which would slow the rate of climate change and mitigate the following negative effects: 

• Increasing temperatures: Earth’s atmosphere has warmed 1.5°C since 1880. This may not seem like a lot, but these degrees create regional and seasonal temperature extremes, reduce sea ice, intensify rainfall and drought severity, and change habitat ranges for plants and animals.

• Rising sea levels: Global sea levels have increased approximately 8-9 inches since 1880, displacing people living along coastlines and destroying coastal habitats. Roads, bridges, subways, water supplies, oil and gas wells, power plants, sewage treatment plants, and landfills remain at risk if sea level rise goes unchecked. 

• Melting of sea ice: Since 1979, arctic sea ice has declined by 30%. Sea ice plays a major role in regulating the earth’s climate by reflecting sunlight into space and providing habitat for animal species. If all of the glaciers on Earth melted, sea levels would rise by approximately 70 feet, effectively flooding out every coastal city on the planet. 

• Changing precipitation patterns: Extreme weather events (e.g., hurricanes, floods, droughts) are becoming more common and more intense. Storm-affected areas will experience increased precipitation and flooding whereas areas located further from storm tracks will experience decreased precipitation and droughts.

• Ocean acidification: The ocean absorbs 30% of the CO₂ released into the atmosphere, which decreases the pH (increases the acidity) of the ocean. In the past 200 years, the pH of oceans has decreased by 0.1 pH units, which translates to a 30% increase in acidity. Aquatic life unable to adjust to this rapid acidification will die off. A prime example of this is coral bleaching, where coral expels the algae (zooxanthellae) living in their tissues as a result of changes in temperature, light, or nutrients. 

Experts claim that to avoid a future plagued by rising sea levels, acidified oceans, loss of biodiversity, more frequent and severe weather events, and other environmental disasters brought on by the hotter temperatures, we must limit global warming to 1.5°C by 2040. 

The more we reduce GHG emissions, the more we slow the rate of temperature rise, sea-level rise, ice melting, and ocean acidification. When these rates are slowed, the earth’s biodiversity does not have to struggle to adapt to temperature and pH changes. People will not be displaced due to the flooding of coastal areas. And icebergs will continue to provide climate regulation. 

Are We on Track to Achieve Absolute Zero/ Zero Emissions Soon Enough

We are not currently on track to achieve absolute zero in time to prevent the worst effects of climate change. We are not even on track to reach net zero by 2050, the target date identified in the Paris Climate Agreement. GHG emissions are predicted to continue to rise despite global, growing momentum and support for the net zero movement. 

What Is the Current Projection of Greenhouse Gas Emissions

The main GHGs emitted by human activity include carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), and fluorinated gasses (F-gasses). The Industrial Revolution brought a rapid increase in emissions that have steadily increased since the mid-1800s.

Under current conditions, global emissions are projected to increase by 9% by 2030 instead of the 45% reduction in emissions needed by 2030 and the 100% reduction in emissions needed by 2050 to achieve net zero.

What Needs to Happen to Achieve Absolute Zero/ Zero Emissions in Time

In 2019, researchers from various UK Universities published the Absolute Zero report, which outlined the means necessary for the UK to reduce its emissions to zero by 2050. The report noted an overreliance on breakthrough technologies (carbon removal offsets) which existed but not at a scale necessary to meet the 2050 deadline.

The report concluded that by 2050, the UK needed to use 40% less energy and electrify all other sources of energy. Phasing out the flying, shipping, and cement industries was also noted as an important measure. 

Globally, we would need to take drastic action, as noted in the Absolute Zero report, to achieve absolute zero. The UK model can be applied to other entities and act as a framework for future climate action.

Is There a Global Effort to Reach Absolute Zero/ Zero Emissions

There is currently no global effort to reach absolute zero. Instead, net zero is the internationally agreed-upon goal for mitigating global warming in the second half of the 21^st century. 

As the climate crisis worsens, momentum and support for the global net zero effort continue to grow. Over 9,000 companies, 1,000 cities, 1,000 educational institutions, and 600 financial institutions have joined the cause and pledged immediate action to cut global emissions by 50% by 2030.

Which Countries Have Absolute Zero/ Zero Emissions Targets

Currently, no countries have an absolute zero target because the goal remains to achieve net zero. To date, over 140 countries have stated a net zero target, covering roughly 88% of the world’s emissions. 

The countries with some of the most ambitious net zero targets include:

• Finland: Achieve net zero by 2035
• Austria: Achieve net zero by 2040
• Sweden: Cut GHG emissions by 59% by 2030 and achieve net zero by 2045
• United Kingdom: Cut GHG emissions by 68% by 2030 and achieve net zero by 2050
• Iceland: Cut GHG emissions by 55% by 2030 and achieve net zero by 2050
• New Zealand: Achieve net zero by 2050
• France: Achieve net zero by 2050

Climate Watch has also developed a net zero tracker that shows each country’s policy documents, their GHG emission targets, and steps they have taken to achieve net zero. 

Absolute Zero/ Zero Emissions and the Paris Climate Agreement

The Paris Climate Agreement (PCA) is the most well-known piece of legally binding, global, international climate mitigation legislation. It aims to limit global warming to below 2 degrees Celsius (°C), preferably to 1.5°C, compared to pre-industrial levels. 

You can check out the highlights of the 2015 COP21 directly from the UN Climate Change channel here:

The PCA dictates we must cut current greenhouse gas (GHG) emissions by 50% by 2030 and reach net zero by 2050 to prevent the worst effects of climate change. 

Does the Paris Climate Agreement Commit Countries to Achieve Absolute Zero/ Zero Emissions

The Paris Climate Agreement (PCA) does not explicitly commit countries to achieve absolute zero. It instead marks the beginning of a shift towards a net-zero emissions world and lays out a framework to limit temperature rise to below 2°C.

In the short term, the PCA requires member parties to produce Nationally Determined Contributions (NDCs), or national climate action plans specific to that party. NDCs dictate actions a party will take to reduce GHG emissions in accordance with PCA goals. Every 5 years, there is an evaluation of collective efforts towards achieving the goals of the PCA and to plan further actions.

In the long term, the PCA sets goals to guide all parties to:

• Limit global warming to below 2°C, preferably to 1.5°C
• Keep track of the collective progress of all parties towards achieving the purpose of the PCA
• Provide financing for developing countries to mitigate climate change

In terms of accountability, there are no hard enforcement measures (e.g., financial penalties) associated with the PCA. Although there are mandatory measures for monitoring, verification, and public reporting of climate mitigation progress for each party, the PCA largely relies on international cooperation and peer pressure to prevent any hypothetical “dragging of feet”.

Which Legislations Are Put In Place to Help Achieve Absolute Zero/ Zero Emissions

Current legislation identifies net zero as our mid-century goal. The most well-known and encompassing piece of legislation to achieve net zero is the Paris Climate Agreement (PCA), which emphasizes we must cut current GHG emissions by 50% by 2030 and reach net zero by 2050 to avoid the worst climate impacts. 

Race to Zero is a global campaign backed by the United Nations Framework Convention On Climate Change (UNFCCC) with the same end goals as the PCA. But whereas the PCA is composed of nations, Race to Zero comprises non-state actors (e.g., companies, cities, financial/educational/healthcare institutions). To date, over 13,000 members have joined the campaign to race towards net zero and a more sustainable future.

Achieving net zero will require a shift from fossil fuels to renewable energy, which the PCA identifies as a critical part of meeting its goals. There are many global and country-specific policies and organizations aimed at increasing the use of renewable resources (e.g., solar, wind, hydropower, geothermal, tidal, wave, and biomass) including:

• 1974 – The International Energy Agency (IEA): The IEA was founded in response to the major oil disruptions in 1974. It promotes international energy cooperation and is made up of 31 member countries. 

• 1988 – The International Geothermal Association (IGA): The IGA is a leading, global organization that promotes geothermal energy as a vital part of the transition away from fossil fuels. Today, the IGA has over 5,000 members and 30 affiliate organizations.

• 1995 – The International Hydropower Association (IHA): The IHA is a nonprofit membership association that serves as a global voice for hydropower energy. They operate in over 120 countries and manage over 1/3^rd of global installed hydropower capacity.

• 2005 – Global Wind Energy Council (GWEC): The GWEC was founded as an international trade association for the wind energy industry. Their members represent 99% of the global installed wind power capacity.

• 2008 – World Bioenergy Association (WBA): The World Bioenergy Association was founded to sustainably develop bioenergy globally and promote the business environment of bioenergy. 

• 2009 – The International Renewable Energy Agency (IRENA): IRENA was founded as a global intergovernmental agency focused on scaling renewable energy. It is comprised of 167 member countries as well as the European Union.

• 2013 – Ocean Energy Europe (OEE): They are the largest global network of marine energy professionals, with over 120 member organizations. They aim to advance tidal and wave energy technologies. 

• 2015 – International Solar Alliance (ISA): The ISA is a treaty-based organization established to create cooperation among solar energy-resource-rich countries and the rest of the world. There are currently 94 member countries.

• 2023 – Global Biofuel Alliance (GBA): The GBA was launched at the G20 summit as an alliance between 19 countries and 12 international organizations to advance the development of sustainable biofuels. 

If you are interested in learning more about country-specific renewable energy policies, you can visit the IEA’s policies database and filter by specific energy type.

How You Can Personally Help to Achieve Absolute Zero/ Zero Emissions

Achieving absolute zero means reducing GHG emissions down to zero across all 3 scopes without the use of carbon offsets. But because this will be difficult and unrealistic for most, net zero has become the internationally agreed-upon goal for mitigating climate change this century.

Net Zero can instigate meaningful environmental change and begin to reverse some of the effects of climate change because it relies on methods of direct carbon reduction first before turning towards carbon offsets.

One of the easiest and most meaningful ways to contribute to the net zero movement is to reduce your carbon footprint. These reduction measures don’t have to involve drastic changes either. Actions that may seem small can have a big impact because those small changes add up! You can directly reduce your carbon footprint in three main areas of your life: household, travel, and lifestyle. 

Reduce your household footprint:

• Wash with cold water: Washing clothes in cold water could reduce carbon emissions by up to 11 million tons. Approximately 90% of the energy is used to heat the water, so switching to cold saves also saves energy.

• Replace incandescent bulbs with fluorescent bulbs: Fluorescent bulbs use 75% less energy than incandescent ones, saving energy and thus reducing electricity demand and GHG emissions.

Reduce your travel footprint:

• Fly less: Aviation accounts for around 1.9% of global carbon emissions and 2.5% of CO₂. Aircraft run on jet gasoline, which is converted to CO₂ when burned.

• Walk or bike when possible: The most efficient ways of traveling are walking, bicycling, or taking the train. Using a bike instead of a car can reduce carbon emissions by 75%. These forms of transportation also provide lower levels of air pollution.

Reduce your lifestyle footprint:

• Switch to renewable energy sources: The six most common types of renewable energy are solar, wind, hydro, tidal, geothermal, and biomass energy. They are a substitute for fossil fuels that can reduce the effects of global warming by limiting global carbon emissions and other pollutants.

• Recycle: Recycling uses less energy and deposits less waste in landfills. Less manufacturing and transportation energy costs means less carbon emissions generated. Less waste in landfills means less CH₄ is generated.

• Switch from single-use to sustainable products: Reusing products avoids resource extraction, reduces energy use, reduces waste generation, and can prevent littering.

• Eat less meat and dairy: Meat and dairy account for 14.5% of global GHG emissions, with beef and lamb being the most carbon-intensive. Globally, we consume much more meat than is considered sustainable, and switching to a vegan or vegetarian diet could reduce emissions. 

• Take shorter showers: Approximately 1.2 trillion gallons of water are used each year in the United States just for showering purposes, and showering takes up about 17% of residential water usage. The amount of water consumed and the energy cost of that consumption are directly related. The less water we use the less energy we use. And the less energy we use, the less of a negative impact we have on the environment.

Final Thoughts

Absolute zero emissions refers to the complete elimination of all greenhouse gas (GHG) emissions across all scopes for all entities. The use of carbon offsets is not permitted to balance out residual emissions.

There is currently no global coalition to achieve absolute zero, but there is a global effort to reach net zero, which aims to reduce emissions just with the added help of offsets. Despite growing momentum for and support of net zero, we are currently a long way off from achieving it before the 2050 deadline as outlined in the Paris Agreement. Greenhouse gas emissions are predicted to increase rather than decrease in the coming years, which further exacerbates global warming. 

Reducing your carbon footprint is one of the easiest and most meaningful ways to contribute to the absolute zero movement. Small actions add up, such as washing in cold water, switching to renewable energy, or eating less meat. 

Stay impactful,

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