Sustainability glossary

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This glossary is a useful guide to commonly used terms and acronyms in the sustainability and climate action space.

The list is not comprehensive nor definitive, as the specific use and interpretation of some of terms may vary dependent on the setting.

Afforestation
The process by which new forests are grown and established, by planting trees across land without trees. This method uses the capability of forests to remove and store CO₂ in addition to promoting improved soil quality and preventing deforestation.

Anthropocene
The time period during which human action has had a significant impact on the geological state of the Earth, impacting biophysical features (natural systems which impact living organisms and their environments) on a global scale.

Anthropogenic
Impacts and/or hazards that occur as a result of the acts or influence of human beings, such as those that (directly or indirectly) result in environmental change.

Article 6 (Paris Agreement)
This is a key section of the Paris Agreement. It establishes a framework for international cooperation on market-based approaches to emissions reduction; outlining permission to pursue voluntary cooperation between countries to this end through Nationally Determined Contributions (NDCs).

More information: https://unfccc.int/process-and-meetings/the-paris-agreement/article-64-mechanism

Avoided emissions
Avoided emissions refer to emissions savings of an organization that that are outside of its value chain, they are part of a broader picture, accelerating decarbonization and progress towards net zero.

Baseline year
A baseline year serves as a historical point of reference, in carbon accounting and carbon footprinting, which enables companies and organizations to track their emissions reductions over time.

Bioenergy with carbon capture and storage (BECCS)
BECCS refers to the process of capturing and permanently storing/sequestering carbon dioxide released from the combustion of bioenergy (energy generated from biomass).

Biofuel
Biofuel is the term used for fuel that is derived from renewable biological resources, such as crops, agricultural residues, or algae, it can be used as a substitute for conventional fossil fuels in most cases, thereby reducing greenhouse gas emissions.

Biomass
Any organic matter that comes from plants or animals, such as plants, wood, or crop residues which can be used as a source of energy through processes like combustion or conversion to biofuels.

Carbon budget
This concept represents the total amount of man-made carbon dioxide which can be emitted while keeping global temperature rise within safe limits, such as those set out in the Paris Agreement.

Carbon capture
Removal of carbon dioxide (CO₂) from the atmosphere. Examples include the process of capturing and storing CO₂ emissions from industrial processes, power plants, or landfills.

Carbon capture and storage (CCS)
This term refers to the use of technology and/or processes to store captured carbon, preventing its release into the atmosphere, this is done by sequestering it underground or in geological formations.

Carbon capture, utilization, and storage (CCUS)
This refers to a process similar to CCS but with an additional process which involves the captured and stored CO₂ being used for beneficial purposes (such as producing chemicals or materials).

Carbon credit
These are transferable/tradable ‘tokens’ certified by governments or independent bodies that represent a measurable and verifiable emissions reduction of one metric ton of CO₂. Credits are issued in the form of a permit or certificate for the reduction or removal of greenhouse gas emissions, this enables organizations or companies to offset their emissions or trade with others.

Also refer to: Carbon offset

Carbon dioxide (CO2)
A colorless, odorless gas, it is one of the of six major greenhouse gases noted by the Kyoto Protocol. CO₂ is primarily emitted as a result of human activities, such as combustion of carbon-based fuels, including fossil fuels, and contributes to global warming.

Also refer to: CO₂e (carbon dioxide equivalent)

Carbon footprint
The total amount of carbon dioxide, and other greenhouse gas emissions generated, either directly or indirectly, by an individual, organization, product, or activity throughout its lifecycle.

Carbon intensity
The amount of carbon dioxide and greenhouse gas emissions that are produced per unit of activity or output. It is commonly used to compare the environmental impact of different sectors, industries, or products. Some examples include CO₂e per unit of revenue, CO₂e per barrel of oil produced, and CO₂ (grams) per kilowatt hour of electricity.

Carbon markets
Carbon markets are trading systems for the buying and selling of carbon credits or permits, they enable entities to meet their emission reduction targets or regulatory requirements.

Carbon offset
A carbon offset, sometimes referred to as a carbon offset credit or offset credit, is a reduction in GHG emissions which is used to enable individuals, companies, or organizations to compensate for a corresponding emission of GHG that happens elsewhere; by investing in projects or activities that remove greenhouse gases from the atmosphere or avoid emissions through another source.

Carbon sequestration
The process of storing captured carbon dioxide from the atmosphere. This can be done through natural or artificial means. Examples of carbon sequestration include reforestation, soil management, and carbon capture and storage technologies.

Carbon sequestration, removal, sink, or carbon dioxide removal (CDR)
This is the process of capturing and removing carbon dioxide from the atmosphere. It is typically done through natural or technological methods, in order to mitigate climate change and reduce GHG concentrations.

Chlorofluorocarbons (CFCs)
Synthetic chemicals of industrial origin made up of atoms of chlorine, fluorine, and carbon. They were commonly used in aerosol propellants, refrigerants, and solvents. In 1987 the international community adopted the Montreal Protocol to phase out the use of CFCs as they deplete the ozone layer, contributing to global warming.

Climate change
Long-term effects on the Earth's temperature and weather patterns resulting from human activities, primarily caused by the burning of fossil fuels and deforestation, leading to global warming and various ecological and societal consequences.

CO₂e (carbon dioxide equivalent)
CO₂ equivalent (CO₂e) is a metric used to standardize and make easily comparable the climate effects of various greenhouse gases. It enables the expression of global warming potential, for various greenhouse gases in terms of their equivalent amount of carbon dioxide.

Also refer to: Global warming potential (GWP)

Conference of the Parties (COP)
The United Nations international climate conference at which countriescome together to discuss and coordinate global climate actions and agreements. It is the primary decision making body of the United Nations Framework Convention on Climate Change (UNFCCC).

Decarbonization

The process of reducing carbon dioxide and other greenhouse gas emissions. Efforts to decarbonize are being made in various sectors, such as energy, transportation, and industry, to combat climate change.

Methods employed include switching from the use of fossil fuel to low or zero carbon and renewable energy.

Direct air capture (DAC)
A technology that extracts carbon dioxide directly from the atmosphere, to mitigate its effect on climate change. DAC is often paired with CCS where the carbon dioxide extracted from the atmosphere is stored underground or in geological formations.

Electrification
Electrification is the process of powering something with electricity. It includes the introduction or conversion of devices or systems that substitute fossil-fuel powered technologies with electrically powered equivalents, such as the replacement of a gas boiler with a heat pump.

Emissions
The production and discharge of substances, in the case of the energy industry, the release of greenhouse gases, predominantly carbon dioxide, methane, and nitrous oxide, into the atmosphere, which contribute to climate change and air pollution.

Energy transition
A global shift in the energy sector from primarily fossil fuel-based energy sources to low-carbon and renewable alternatives. It requires long-term energy strategies and planning, tailored to countries and regions, that leverage appropriate energy technologies to reach net-zero emissions.

Environmental, social, and governance (ESG)
ESG is a framework used to assess an organization's business practices and performance on various sustainability and ethical issues; encompassing environmental practices, social responsibility, and governance standards.

Emissions trading system (ETS)
These represent market-based approaches to regulate greenhouse gas emissions and require companies to buy or trade permits for their emissions. Schemes may be adopted by sector or by region, regional examples include the European Union (EU ETS), United Kingdom (UK ETS), or Swiss ETS.

Global warming
The gradual, long-term rise in Earth's average atmospheric and oceanic temperatures, caused primarily by human activities, such as fossil fuel use and deforestation, that release greenhouse gases into the atmosphere, trapping heat, and ultimately causing irregular weather patterns globally.

Global warming potential (GWP)
GWP is a measure developed to enable the comparison of the amount of infrared thermal radiation absorbed by different greenhouse gases in a given period of time, relative to carbon dioxide.

Green taxonomy
A classification system that identifies sustainable economic activities and sectors; according to clearly defined criteria related to environmental, economic, and social sustainability.

Greenhouse gases (GHG)
Gases in the atmosphere that trap heat from the sun thereby contributing to the increase in the Earth’s surface temperature. They include carbon dioxide (CO₂), methane (CH4), nitrous oxide (N2O), fluorinated gases (CFC, HCFC, HFC, PFC), and sulfur hexafluoride (SF6).

Hard-to-abate industries
Hard-to-abate industries are those for whom it is particularly difficult to lower their greenhouse gas emissions, some examples are steel, chemical, cement, and refining.

Hydrogen
Hydrogen is a colorless, odorless gas, and can be used as a fuel, when it comes to its production it has many colorful names depending on the method used to produce it. Some of these are:

• Blue hydrogen—produced using natural gas, predominately through a steam reforming process that produces carbon dioxide as a byproduct, this carbon dioxide is then trapped and stored using carbon capture and storage (CCS).

• Gray hydrogen—produced from natural gas or methane but unlike blue hydrogen the carbon dioxide produced is not captured. This is the most common form of hydrogen production today.

• Green hydrogen—produced using energy from renewable sources such as wind or solar power.

• Pink hydrogen—produced using electrolysis and is powered by nuclear energy.

International Sustainability Standards Board (ISSB)
An independent, private-sector, global body which develops and sets sustainability reporting and disclosure standards, operating under the oversight of the International Financial Reporting Standards (IFRS) Foundation.

Intergovernmental Panel on Climate Change (IPCC)
The IPCC is a UN intergovernmental scientific body, that assesses and provides policymakers with scientific information on climate change, its impacts, and potential adaptation and mitigation measures.

Kyoto Protocol
An international agreement which operationalizes the United Nations Framework Convention on Climate Change. It was adopted on December 11, 1997, and due to a complex ratification process, it entered into force on February 16, 2005. It sets binding emissions reduction targets for developed countries and implementation mechanisms to achieve these targets.

Lifecycle analysis (LCA)
A systemic analysis which measures and evaluates the environmental impact created throughout the entire lifecycle of a product, process, material, activity, or service.

Methane
One of the six major greenhouse gases noted by the Kyoto Protocol, methane is a is a potent greenhouse gas. It is produced by both natural and human-caused sources, such as plant-matter breakdown in wetlands, landfills, and rice farming, and fossil fuel extraction. Methane has a global warming potential 80 times that of carbon dioxide over a 20 year period, and 20 times that of carbon dioxide over a 100 year period.

Measurement, monitoring, and verification (MMV)
Measurement, monitoring, and verification in relation to a CCUS/CCS project, is the ability or plan to measure the amount of carbon dioxide sequesters at a specific site, monitor that site for leaks and any other reduction/ deterioration in storage integrity, and verify that the carbon dioxide is stored in a way which does not harm the host ecosystem.

Measurement, reporting, and verification (MRV)
The collection and use of data for the performance of calculations needed to estimate reduction of emissions or the enhancement of stocks and associated uncertainties, when compared to a reference/baseline level.

Nationally determined contributions (NDCs)
Required by the Paris Agreement they are efforts by signatory countries to mitigate greenhouse gas emissions and adapt to climate change. They are outlined in specific targets, policies, and measures, and updated every five years.

Also refer to: Paris Agreement

Nature based solutions
Actions and approaches to protect, manage, and restore natural and modified ecosystems that utilize the natural environment to benefit both people and nature. Examples of such efforts include reforestation, ecosystem restoration, and green infrastructure.

Nature based removals
Nature based removals, sometimes know as nature based carbon removals, are solutions for GHG removal or reduction through use of natural habitats, such as coastal or marine habitats with mangroves or sea grass, or land use through the growth of new forests (afforestation) or re-establishment of forests (reforestation).

Net zero
The term net zero refers to the negation of the amount of greenhouse gases produced through direct emissions reduction measures and methods of carbon removal (such as sequestration, absorption, capture, use, and storage). Typically, a target is set against a baseline year for an entity.

Perfluorocarbons (PFCs)
Potent, synthetic greenhouse gases used in various industrial applications, they are composed of fluorine and carbon. They are one of six major greenhouse gases noted by the Kyoto Protocol.

Paris Agreement
The Paris Agreement was adopted by 196 parties at the UN Climate Change Conference (COP21) in Paris, France, 12 December 12, 2015 it is a legally binding international treaty on climate change and came into force on 4 November 2016.

Product carbon footprint (PCF)
The total sum of greenhouse gas emissions that are generated over the entire lifecycle of a product.

Reducing Emissions from Deforestation and Forest Degradation (REDD+)
Established as part of the Paris Agreement this is a framework for the protection of forests. It relates to nature based solution classification of projects.

Science Based Targets Initiative (SBTi)
An initiative formed as a collaboration between the CDP, the United Nations Global Compact, World Resources Institute, and the World Wide Fund for Nature. It aims to provide a clearly defined, scientific pathway for companies and financial institutions to set reasonable and achievable targets to reduce greenhouse gas emissions.

Scope 1 emissions
Scope 1 emissions are the greenhouse has (GHG) emissions created directly by sources that are controlled or owned by the company e.g. by the burning of fuel in non-electrically powered vehicles.

Scope 2 emissions
Scope 2 emissions are those GHG emissions created indirectly as a result of the energy purchased and used by the company. An example of this is the emissions created in the generation of the electricity used to power office buildings an organization operates.

Scope 3 emissions
Scope 3 emissions are all those indirect GHG emissions, that are not included within scope 2, but that occur within the entire value chain of the company. The 15 categories of scope 3 emissions are: purchased goods and services, capital goods, fuel and energy related activities, upstream transportation and distribution, waste generated in operations, business travel, employee commuting, upstream leased assets, downstream transportation and distribution, processing of sold products, use of sold products, end-of-life treatment of sold products, downstream leased assets, franchises, and investments.

Scope 3 downstream emissions
Scope 3 emissions related to the use phase of products.

Scope 3 upstream emissions
Scope 3 emissions related to materials and services purchased.

Sustainable aviation fuel (SAF)
SAF is an alternative fuel made from renewable biomass and/or waste resources. It meets specific sustainability conditions for carbon emissions reduction, and is defined as renewable, waste-derived, or low- carbon aviation fuel.

Sustainable development goals (SDG)
The Sustainable Development Goals (SDGs), also known as the global goals, were adopted by all member states of the United Nations in 2015. They represent an urgent call for action by all countries, both developed and developing, to act in a global partnership. There are 17 goals in total:

1. No poverty
2. Zero hunger
3. Good health and well-being
4. Quality education
5. Gender equality
6. Clean water and sanitation
7. Affordable and clean energy
8. Decent work and economic growth
9. Industry, innovation, and infrastructure
10. Reduced inequalities
11. Sustainable cities and communities
12. Responsible consumption and production
13. Climate action
14. Life below water
15. Life on land
16. Peace, justice, and strong institutions
17. Partnership for the goals

Taskforce on Climate-Related Financial Disclosures (TCFD)
TCFD is a body which provides reporting, information, and transparent analysis and guidance to investors and agencies regarding climate action efforts by companies.

Technology based removals
These are removal systems for carbon capture which can collect and store carbon from the atmosphere, examples include direct air carbon capture and storage (DACCS), and bio-energy with carbon capture and storage (BECCS). These require the introduction or scale-up of technology systems, as opposed to natural or nature-based carbon removal systems (such as trees).

The United Nations Framework Convention on Climate Change (UNFCCC)
An international treaty, which came into force on March 21, 1994, is now ratified by 198 countries, and aims to stabilize GHGs "at a level that would prevent dangerous anthropogenic (human induced) interference with the climate system."