Carbon Neutral, Net Zero, and Climate Neutral
You have probably read or heard a news story that contained at least one of these three terms: carbon neutral, net zero, and climate neutral. If you have ever wondered about the meaning behind these terms, here is a quick guide.
Do these phrases mean the same thing?
All three phrases refer to a state in which anthropogenic (human induced) emissions are being reduced or in which anthropogenic emissions are supposedly balanced in a 1:1 ratio with projects that take emissions out of the atmosphere (example: planting new trees).
In general, this means that an organization or government is working towards reducing the emissions that are within the boundaries of the organization or government. These terms are often used interchangeably, but there are subtle differences.
Carbon Neutral: A state in which anthropogenic carbon dioxide emissions are at a constant level.
Net Zero: A state in which anthropogenic emissions are at a constant level. This state is like carbon neutral but includes other emissions, such as methane, hydrofluorocarbons, nitrous oxide, etc.
Climate Neutral: A state in which anthropogenic emissions and bio geophysical effects are at a constant level. Bio geophysical effects are factors other than emissions, like surface albedo (reflected sunlight) or local climate.
How do we reach these states?
For any kind of organization, this usually means setting targets that limit global warming to 1.5 °C, a threshold that has been suggested by the Intergovernmental Panel on Climate Change (aka IPCC). It also means committing to a year in which the state of neutrality will be reached.
As an example, in 2019, the European Union agreed to the objective of the EU becoming carbon neutral by 2050. The European Commission has also released the European Green Deal, a written strategy for reaching carbon neutrality within the EU. The gist of the strategy is that the EU would direct more funding (30%) to climate mitigation efforts. These efforts include investing in environmentally friendly technologies, renewable energy infrastructures, cleaner forms of transportation, more energy efficient buildings, and improved standards of living around the world. If the strategy is successful, the EU would be the first content to reach a net-zero emissions balance.
As another example, the Dallas Fort Worth International Airport (DFW) has been recognized for being the first carbon neutral airport in the Americas. The airport reached this goal in 2019 after working towards this lofty goal for more than a decade. Since 2010, DFW has reduced carbon emissions per passenger by 83% and has reduced energy costs by $35 million. Most reductions have been attributed to the purchase of 100% renewable energy, more specifically through wind energy. The airport has also committed to diverting trash from landfills via recycling and to reducing the number of buses on site by switching to a train link. While the airport has reached the goal of carbon neutrality, the airport is still working on improvements. One example of this is the installment of deploying sensors, which track real time data on energy usage, so the airport can further its efforts to be more efficient.
Like the European Union’s commitment, DFW started with a strategic plan. Both organizations united leaders from across sectors/departments and both used current greenhouse gas emission data to identify opportunities for movement towards carbon neutrality.
Is this greenwashing?
In short, probably.
There are multiple ways an organization can meet goals around carbon neutrality, net zero, and climate neutrality and no standard for reaching these goals. One of these ways is by purchasing carbon offsets, also known as carbon credits. In essence, an organization is paying someone else to avoid greenhouse gases or to remove emissions. It is kind of like paying someone to pick up liter in their neighborhood to justify littering your own neighborhood. It does do some good, but the problem is still there.
It is quite easy for an organization to use accounting tricks to make it seem like an organization is doing more for the environment than it is. In the case of carbon credits, every carbon credit is of equal value, but some projects may be more effective than others. There are also many companies who have net-zero goals, but these targets have a limited scope, or the company lacks action steps for achieving these goals.
Going back to the DFW example, the airport’s scope is limited to the airport itself. There is no getting around the fact that the airport is still selling rides on airplanes. In 2019, airplanes accounted for 2.5% of the world’s CO2 emissions. One flight can emit as much CO2 emissions as many people do in one year of living. Aviation is also tricky because domestic flights are counted in a country’s overall emissions, but international flights are not. This means that there are very few incentives for countries to reduce emissions from international flights.
While shady climate commitments and accounting tricks do exist, this trend towards net zero is getting leaders to consider their organizations’ greenhouse gas emissions. DFW is still implementing more sustainable practices and working to improve, which could influence other airports to initiate similar and hopefully better practices. Progress is still better than no change at all, even though there is significant room for improvement.
Albert, B. (2020, October 20). What is the meaning of ‘carbon neutral’, ‘net zero’ and ‘climate neutral’? YouTube. https://www.youtube.com/watch?v=T0CeOPCRXv4.
Council of the European Union. (2020, October 13). 5 facts about the EU’s goal of climate neutrality. Council of the European Union. https://www.consilium.europa.eu/en/5-facts-eu-climate-neutrality/.
European Parliament. (2021, June 24). Green Deal: key to a climate-neutral and sustainable EU: News: European Parliament. Green Deal: key to a climate-neutral and sustainable EU | News | European Parliament. https://www.europarl.europa.eu/news/en/headlines/priorities/climate-change/20200618STO81513/green-deal-key-to-a-climate-neutral-and-sustainable-eu.
Matthews, J. B. R. (2019). Annix 1: Glossary. Intergovernmental Panel on Climate Change. https://www.ipcc.ch/site/assets/uploads/sites/2/2019/06/SR15_AnnexI_Glossary.pdf.
Ritchie, H. (2020, October 22). Climate change and flying: what share of global CO2 emissions come from aviation? Our World in Data. https://ourworldindata.org/co2-emissions-from-aviation.
Sustainability/Environmental. DFW International Airport. (n.d.). https://www.dfwairport.com/business/community/sustainability/.
Timperley, J. (2021, May 25). The fastest ways aviation could cut emissions. Future Planet. https://www.bbc.com/future/article/20210525-how-aviation-is-reducing-its-climate-emissions.
The World Needs Better Climate Pledges. Project Drawdown. (2021, June 22). https://drawdown.org/news/insights/the-world-needs-better-climate-pledges.