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Glossary of CO2 Capture and Removal of Terms

Your Essential Guide to Key Concepts and Terms

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45Q tax credit: A U.S. federal tax credit for CO2 sequestration, which provides incentives for capturing and storing CO2 from industrial sources or the atmosphere. The credit is available for qualifying projects that capture and store CO2 or use it for enhanced oil recovery (EOR).
See also: carbon capture, CO2 sequestration, EU Innovation Fund, Inflation Reduction Act
Additionality: The principle that a carbon offset project should result in emission reductions that would not have occurred without the incentive provided by the offset credit. Additionality ensures that offset projects lead to genuine, additional reductions in greenhouse gas emissions.
See also: carbon offset, carbon credit, greenwashing
Afforestation: The process of planting trees in areas where there were no forests before, with the aim of sequestering carbon and promoting other ecosystem services. Afforestation helps to increase carbon storage in biomass and soils while providing habitat for wildlife.
See also: reforestation, forest conservation
Amine absorption: A post-combustion carbon capture process that uses amine-based solvents to absorb CO2 from flue gases. The absorbed CO2 is then stripped from the solvent and compressed for transportation and storage.
See also: post-combustion, carbon capture, CO2 absorption
Anthropogenic CO2: CO2 emissions resulting from human activities, such as burning fossil fuels or land-use changes. Anthropogenic CO2 is the primary driver of climate change, as it accumulates in the atmosphere and enhances the greenhouse effect.
See also: fossil carbon, greenhouse gases, global warming
BECCS - Bioenergy with Carbon Capture and Storage: A negative emissions technology that combines biomass energy production with carbon capture and storage. BECCS involves growing biomass, which absorbs CO2 from the atmosphere, and then burning it for energy while capturing and storing the resulting CO2 emissions.
See also: negative emissions technologies (NETs), biomass, carbon capture, CO2 storage
Biochar: A charcoal-like substance produced by heating biomass in a low-oxygen environment (pyrolysis). Biochar can be used as a soil amendment to improve soil fertility and sequester carbon in the soil for long periods.
See also: soil carbon sequestration, biomass, carbon sequestration
Biodiversity: The variety of life forms within an ecosystem, including the diversity of species, genetic diversity within species, and the diversity of ecosystems. Maintaining biodiversity is crucial for the resilience and functioning of ecosystems and can be affected by climate change and land-use practices.
See also: nature-based solutions, afforestation
Biogenic carbon: Carbon derived from living organisms or biological processes. Biogenic carbon is part of the short-term carbon cycle and can be considered carbon-neutral if the biomass is sustainably managed.
See also: biomass, short-term carbon cycle, fossil carbon
Biomass: Organic matter derived from living organisms, which can be used as a renewable energy source or for carbon sequestration. Biomass plays a crucial role in the global carbon cycle and can help mitigate climate change when used sustainably.
See also: biogenic carbon, BECCS, biochar
Blue carbon: Carbon captured and stored by coastal and marine ecosystems, such as mangroves, salt marshes, and seagrass meadows. These ecosystems can sequester and store large amounts of carbon in their biomass and sediments, making their conservation and restoration important for climate change mitigation.
See also: carbon sequestration, nature-based solutions,
Blue hydrogen: Hydrogen produced from natural gas through steam methane reforming, with the resulting CO2 emissions captured and stored using CCS technology. Blue hydrogen is considered a low-carbon alternative to conventional hydrogen production, which releases CO2 into the atmosphere.
See also: CCS - carbon capture and storage
Cap-and-trade: A market-based approach to reducing greenhouse gas emissions, where a government sets a limit (cap) on the total amount of emissions allowed by a sector or economy, and issues tradable permits or allowances to emit a specific quantity of emissions. Companies that reduce their emissions below their allocated amount can sell their excess allowances to other companies that exceed their limits, creating a financial incentive to reduce emissions.
See also: emission trading, carbon market, carbon pricing
Carbon accounting: The process of measuring, tracking, and reporting greenhouse gas emissions and removals at various scales, such as individual projects, organizations, or nations. Carbon accounting is essential for understanding the sources and sinks of carbon and informing strategies for reducing emissions and enhancing removals.
See also: carbon footprint, carbon budget, carbon management
Carbon budget: The estimated amount of cumulative carbon dioxide emissions that can be released into the atmosphere while limiting global warming to a specific temperature target, such as 1.5°C or 2°C above pre-industrial levels. Carbon budgets help guide global and national efforts to reduce emissions and achieve climate goals.
See also: carbon accounting, Paris Agreement, net zero emissions
Carbon capture: The process of capturing CO2 from emission sources or the atmosphere to prevent its release into the atmosphere. Carbon capture can be achieved through various methods, such as point source capture, direct air capture, or biomass-based approaches, and is a key component of many CO2 removal strategies.
See also: point source emissions, DAC - direct air capture, BECCS, CO2 removal
Carbon capture technologies: Various methods and technologies used to capture CO2 from emission sources or the atmosphere, including post-combustion capture, pre-combustion capture, oxy-fuel combustion, and direct air capture. These technologies differ in their approach, efficiency, and applicability to different emission sources.
See also: post-combustion, pre-combustion, oxyfuel combustion, DAC - direct air capture
Carbon cluster: A geographical concentration of interconnected businesses, suppliers, and associated institutions involved in the carbon management value chain, including carbon capture, utilization, and storage. Carbon clusters foster collaboration, innovation, and knowledge sharing among stakeholders to accelerate the deployment of carbon management solutions.
See also: carbon hub, CCUS - carbon capture and storage/sequestration, carbon utilization
Carbon credit: A tradable certificate or permit representing the right to emit one tonne of carbon dioxide or an equivalent amount of another greenhouse gas. Carbon credits are used in Emission Trading schemes and voluntary Carbon Markets to incentivize emission reductions and support carbon offset projects.
See also: emission trading, carbon offset, voluntary carbon market
Carbon cycle: The continuous movement of carbon through the Earth's atmosphere, biosphere, oceans, and geosphere. The carbon cycle involves processes such as photosynthesis, respiration, decomposition, and geological storage, which regulate the exchange of carbon between different reservoirs. Understanding the carbon cycle is crucial for managing the global carbon balance and mitigating climate change.
See also: short-term carbon cycle, long-term carbon cycle, carbon sink
Carbon dioxide equivalent (CO2e): A standardized measure used to compare the global warming potential (GWP) of different greenhouse gases by expressing their impact in terms of the equivalent amount of carbon dioxide (CO2). The CO2e value is calculated by multiplying the quantity of a greenhouse gas by its GWP, which takes into account the gas's ability to absorb heat and its atmospheric lifetime relative to CO2.
See also: greenhouse gases, carbon footprint
Carbon footprint: The total amount of greenhouse gas emissions caused directly and indirectly by an individual, organization, event, or product, expressed in carbon dioxide equivalent (CO2e). Measuring and reducing carbon footprints is an important aspect of climate change mitigation efforts.
See also: carbon accounting, lifecycle emissions,
Carbon hub: A centralized infrastructure network designed to collect, transport, and store CO2 from multiple emission sources, such as industrial facilities or power plants. Carbon hubs enable the efficient management and storage of captured CO2, facilitating the deployment of carbon capture, utilization, and storage (CCUS) technologies at scale.
See also: carbon cluster, CCUS - carbon capture and storage/sequestration, CO2 transportation
Carbon leakage: The situation that occurs when businesses transfer their production to countries with less stringent emission constraints, leading to an increase in total emissions. Carbon leakage can undermine the effectiveness of climate policies and requires international coordination to address.
See also: emission trading, carbon pricing, EU Carbon Border Adjustment Mechanism (CBAM)
Carbon lifecycle analysis: A method for assessing the total greenhouse gas emissions associated with a product or service throughout its entire lifecycle, from raw material extraction to disposal. Carbon lifecycle analysis provides a comprehensive understanding of a product's carbon footprint and helps identify opportunities for reducing emissions at different stages.
See also: carbon footprint, lifecycle emissions,
Carbon management: The strategic approach to measuring, reducing, and offsetting an organization's carbon footprint, encompassing a range of practices such as carbon accounting, emission reduction strategies, and investment in carbon offset projects. Effective carbon management helps organizations align with global climate goals and transition to a low-carbon economy.
See also: carbon accounting, carbon offset
Carbon market: A market-based system that allows the trading of carbon credits or allowances to incentivize emission reductions and support low-carbon technologies. Carbon Markets can be either compliance-based, such as cap-and-trade systems, or voluntary, such as the voluntary Carbon Market.
See also: carbon credit, emission trading, compliance market, voluntary carbon parket
Carbon neutral: A state in which the net greenhouse gas emissions associated with an entity, product, or activity are zero, either through the absence of emissions or by balancing emissions with an equivalent amount of carbon removal or offset. Achieving carbon neutrality is a common goal for organizations and individuals aiming to minimize their climate impact.
See also: net zero emissions, carbon offset,
Carbon offset: A reduction in greenhouse gas emissions or an increase in carbon sequestration that is used to compensate for emissions occurring elsewhere. Carbon offsets are typically generated by projects such as renewable energy development, energy efficiency improvements, or nature-based solutions, and can be bought and sold on Carbon Markets.
See also: carbon credit, carbon market, additionality
Carbon pricing: A policy approach that puts a price on greenhouse gas emissions to incentivize emission reductions and shift investment towards low-carbon technologies. Carbon Pricing can take the form of a carbon tax, where emitters pay a fixed price per unit of emissions, or an Emission Trading system, where emitters trade emission allowances under a cap.
See also: carbon tax, emission trading, carbon market
Carbon sequestration: The process of capturing and storing atmospheric carbon dioxide in long-term reservoirs, such as oceans, soils, vegetation, or geological formations. Carbon sequestration can occur naturally or be enhanced through various methods, such as afforestation, soil carbon storage, or carbon capture and storage technologies.
See also: carbon capture, CO2 storage, nature-based solutions
Carbon sink: A natural or artificial reservoir that absorbs and stores more carbon than it releases, helping to remove CO2 from the atmosphere. Examples of natural carbon sinks include oceans, forests, and soils, while artificial carbon sinks can be created through carbon capture and storage technologies.
See also: carbon sequestration, blue carbon, soil carbon storage
Carbon tax: A policy instrument that imposes a tax on greenhouse gas emissions, typically based on the carbon content of fossil fuels. The aim of a carbon tax is to internalize the external costs of emissions and encourage a shift towards low-carbon alternatives by making emissions more expensive.
See also: carbon pricing,
Carbon utilization: The process of using captured CO2 as a feedstock for the production of valuable products, such as fuels, chemicals, building materials, or consumer goods. Carbon utilization can help create a circular economy for carbon and incentivize the deployment of carbon capture technologies.
See also: CCUS - carbon capture and usage or storage/sequestration
CBAM: EU Carbon Border Adjustment Mechanism: A proposed policy tool that would apply a carbon price to certain goods imported into the European Union from countries with less stringent climate policies. The CBAM aims to prevent carbon leakage and ensure a level playing field for EU producers subject to the EU Emissions Trading System.
See also: carbon leakage, emission trading, carbon pricing
CCS - carbon capture and storage: A process that involves capturing CO2 from emission sources, transporting it, and storing it in deep geological formations to prevent its release into the atmosphere. CCS is considered a key technology for mitigating emissions from large-scale fossil fuel use and industrial processes.
See also: carbon capture, CO2 transportation, CO2 storage
CCUS - carbon capture and storage/sequestration: An extended version of CCS that includes the utilization of captured CO2 in addition to its storage. CCUS encompasses a wider range of applications for captured CO2, such as enhanced oil recovery, chemical production, or mineral carbonation.
See also: CCS - carbon capture and storage, carbon utilization, enhanced oil recovery (EOR)
CCUS - carbon capture and usage or storage/sequestration: An umbrella term that covers both the storage and utilization aspects of captured CO2. CCUS emphasizes the potential for creating value from captured CO2 while also ensuring its long-term removal from the atmosphere.
See also: CCS - carbon capture and storage, carbon utilization
CDR - Carbon dioxide removal: The process of removing CO2 from the atmosphere through various methods, such as direct air capture, enhanced weathering, or nature-based solutions. CDR is considered necessary to achieve net-zero emissions and limit global warming, as it can offset hard-to-abate emissions and potentially enable net-negative emissions.
See also: DAC - direct air capture, enhanced weathering/mineralization, nature-based solutions
Chemical looping combustion: A combustion process that uses metal oxides as oxygen carriers to separate the combustion of fuel from the air, resulting in a concentrated stream of CO2 that is easier to capture. Chemical looping combustion can be applied to power generation and industrial processes to facilitate carbon capture and storage.
See also: oxyfuel combustion, post-combustion, CCS - carbon capture and storage
Climate change: The long-term change in the Earth's climate patterns, including temperature, precipitation, and weather events, primarily driven by the increase in atmospheric greenhouse gas concentrations due to human activities. Climate change has wide-ranging impacts on natural systems, human societies, and the economy, such as rising sea levels, more frequent and intense extreme weather events, changes in species distribution and ecosystem functioning, and risks to human health and food security. Addressing climate change requires a combination of mitigation efforts to reduce greenhouse gas emissions and adaptation measures to build resilience to its impacts.
See also: global warming, greenhouse gases, climate change mitigation,
Climate change mitigation: Actions and strategies aimed at reducing greenhouse gas emissions and enhancing carbon sinks to limit the extent and impacts of climate change. Climate change mitigation measures include transitioning to low-carbon energy sources, improving energy efficiency, promoting sustainable land use and forest management, and deploying carbon capture and storage technologies. Effective mitigation efforts are crucial for achieving the goals of the Paris Agreement and avoiding the worst consequences of climate change.
See also: decarbonization, Paris Agreement
CO2 absorption: The process by which CO2 is taken up by a liquid or solid, such as in the case of ocean uptake or chemical solvents used in carbon capture. CO2 absorption is a key mechanism for removing CO2 from the atmosphere and storing it in various reservoirs.
See also: carbon capture, ocean carbon cycle, amine absorption
CO2 adsorption: The process by which CO2 adheres to the surface of a solid material, such as in the case of certain carbon capture technologies. CO2 adsorption is a promising approach for capturing CO2 from emission sources or the atmosphere, as it can be more selective and efficient than absorption-based methods.
See also: carbon capture, DAC - direct air capture
CO2 removal: The process of removing CO2 from the atmosphere through various methods, such as direct air capture, enhanced weathering, or nature-based solutions. CO2 removal is necessary to achieve net-zero emissions and limit the impacts of climate change, as it helps to counterbalance hard-to-abate emissions.
See also: CDR - carbon dioxide removal, negative emissions, Net Zero Emissions
CO2 sequestration: The process of capturing and storing CO2 in long-term reservoirs to prevent its release into the atmosphere. CO2 sequestration can be achieved through various methods, such as geological storage, ocean storage, or mineral carbonation, and is a critical component of many climate change mitigation strategies.
See also: Carbon sequestration, Geological Storage, Ocean carbon cycle
CO2 Storage: The long-term containment of captured CO2 in suitable reservoirs, such as deep saline aquifers, depleted oil and gas reservoirs, or deep ocean waters. Secure and permanent CO2 Storage is essential for the effectiveness of carbon capture and storage in mitigating climate change.
See also: Geological Storage, Ocean carbon cycle, Mineral carbonation
CO2 transportation: The process of moving captured CO2 from its source to a storage site, typically via pipelines, ships, or trucks. Developing efficient and safe CO2 transportation infrastructure is crucial for the large-scale deployment of carbon capture and storage technologies.
See also: CCS - Carbon Capture and Storage, carbon hub, Pipeline transport
Combustion emissions: Greenhouse gas emissions, primarily CO2, that are released into the atmosphere as a result of burning fossil fuels, such as coal, oil, or natural gas, for energy production, transportation, or industrial processes. Combustion emissions are the largest contributor to anthropogenic greenhouse gas emissions and are a major driver of climate change. Reducing combustion emissions through the adoption of clean energy technologies, energy efficiency improvements, and fuel switching is crucial for mitigating climate change and achieving decarbonization goals.
See also: Process emissions, Fossil fuels, Anthropogenic CO2, Decarbonization,
Compliance carbon market: A market created by government regulations that require companies to limit their greenhouse gas emissions, often through a cap-and-trade system or a carbon tax. In compliance markets, companies can trade emission allowances or credits to meet their regulatory obligations.
See also: Carbon Market, Emission Trading, Carbon Pricing, Voluntary Carbon Market
Decarbonization: The process of reducing the carbon intensity of the economy by shifting away from fossil fuels and other carbon-intensive activities towards low-carbon or zero-carbon alternatives. Decarbonization involves a systemic transformation of energy systems, transportation, industry, and land use to achieve deep emission reductions and limit global warming. Key strategies for decarbonization include increasing the use of renewable energy, electrifying end-use sectors, improving energy efficiency, and deploying carbon capture and storage technologies.
See also: Carbon capture, Renewable energy
Deforestation: The permanent removal or clearing of forests for non-forest uses, such as agriculture, urbanization, or mining. Deforestation is a significant contributor to climate change, as it releases the carbon stored in trees and soil back into the atmosphere and reduces the Earth's capacity to absorb CO2 through photosynthesis. Deforestation also has negative impacts on biodiversity, water cycles, and local communities that depend on forest resources. Reducing deforestation and promoting sustainable forest management are important strategies for mitigating climate change and achieving sustainable development goals.
See also: Land-use change, Carbon Cycle, Forest conservation
Depleted oil and gas reservoirs: Former oil and gas extraction sites that can be repurposed for long-term CO2 Storage. These reservoirs have a proven ability to contain fluids and gases over geological timescales, making them suitable for secure CO2 Storage.
See also: CO2 Storage, Geological Storage, Enhanced Oil Recovery (EOR)
Direct air capture (DAC):An approach to removing CO2 from the atmosphere by chemically binding it to a sorbent material, and then releasing it as a concentrated stream for storage or utilization. DAC has the potential to be deployed at a large scale and can remove CO2 from the atmosphere regardless of its source.
See also: DAC - direct air capture, CDR - Carbon dioxide removal, Negative emissions
Emission trading: A market-based approach to reducing greenhouse gas emissions, where a cap is set on the total amount of emissions allowed, and companies can trade emission allowances among themselves. Emission Trading creates a financial incentive for companies to reduce their emissions and invest in clean technologies.
See also: Carbon Market, Carbon Pricing, Cap-and-trade
Enhanced oil recovery (EOR): A technique that involves injecting CO2 into depleted oil reservoirs to increase oil production while also storing the CO2 permanently underground. EOR can help offset the costs of carbon capture and storage and contribute to reducing atmospheric CO2 levels.
See also: CCUS - carbon capture and storage/sequestration, Depleted oil and gas reservoirs
Enhanced weathering/mineralization: A process that involves accelerating the natural weathering of rocks to increase their uptake of atmospheric CO2. Enhanced weathering can be achieved by spreading finely ground silicate rocks on land or ocean surfaces, where they react with CO2 to form stable carbonate minerals.
See also: CDR - Carbon dioxide removal, Ocean alkalinization, Mineral carbonation
EU Emissions Trading System (EU ETS): The cornerstone of the European Union's policy to combat climate change and its key tool for reducing greenhouse gas emissions cost-effectively. It is the world's first major carbon market and remains the largest. The EU ETS operates on the 'cap and trade' principle, where a cap is set on the total amount of certain greenhouse gases that can be emitted by installations covered by the system. Within this cap, companies receive or buy emission allowances, which they can trade with one another as needed. The cap is reduced over time so that total emissions fall. Launched in 2005, the EU ETS covers about 40% of the EU's greenhouse gas emissions, focusing on sectors such as power and heat generation, energy-intensive industrial sectors, and aviation within Europe.
See also: cap and trade, carbon pricing, carbon market
EU Innovation Fund: One of the world's largest funding programs for the demonstration of innovative low-carbon technologies. Established by the European Union, it supports breakthrough technologies for renewable energy, energy-intensive industries, energy storage, and carbon capture, use and storage. The fund aims to bring to the market industrial solutions to decarbonize Europe and support its transition to climate neutrality. It is financed by revenues from the EU Emissions Trading System (ETS) and is expected to provide around €38 billion of support over the period 2020-2030, depending on the carbon price.
See also: EU Emissions Trading System (ETS), Decarbonization
Forest conservation: The protection and management of existing forests to maintain their carbon storage capacity and biodiversity. Forest conservation is crucial for preventing the release of stored carbon and ensuring the continued provision of ecosystem services, such as water regulation and habitat protection.
See also: Nature-Based Solutions, Carbon sink, Biodiversity
Fossil carbon: Carbon stored in fossil fuels, such as coal, oil, or natural gas, which is released as CO2 when burned. Fossil carbon has been locked away in the Earth's crust for millions of years, and its rapid release through human activities is the primary driver of climate change.
See also: Anthropogenic CO2, greenhouse gases, Carbon budget
Fossil fuels: Non-renewable energy sources formed from the buried remains of plants and animals that lived millions of years ago, which have been converted into combustible materials through geological processes. The main types of fossil fuels are coal, oil, and natural gas. When burned, fossil fuels release carbon dioxide (CO2) and other greenhouse gases into the atmosphere, contributing significantly to climate change. Transitioning away from fossil fuels and towards clean, renewable energy sources is crucial for mitigating climate change and achieving decarbonization goals. [See also: Anthropogenic CO2, Combustion emissions, Decarbonization, Renewable energy]
Geological storage: The long-term storage of CO2 in deep geological formations, such as depleted oil and gas reservoirs, saline aquifers, or deep coal seams. Geological storage is a key component of carbon capture and storage (CCS) and has the potential to securely store large amounts of CO2 for thousands of years.
See also: CO2 Storage, CCS - Carbon Capture and Storage, Depleted oil and gas reservoirs
Gigatonne levels: A unit of measurement used to quantify large amounts of greenhouse gas emissions or removals, equivalent to one billion metric tonnes. Gigatonne levels are often used to discuss global emission reduction targets or the scale of carbon dioxide removal needed to achieve climate goals.
See also: Carbon budget, Net Zero Emissions, Negative emissions
Global warming: The long-term increase in Earth's average surface temperature, primarily driven by the rise in atmospheric greenhouse gas concentrations due to human activities. Global warming is a key aspect of climate change and has wide-ranging impacts on natural systems, human societies, and the economy.
See also: greenhouse gases, Anthropogenic CO2, Climate change
Greenhouse gas removal (GGR): The process of removing greenhouse gases, particularly CO2, from the atmosphere through various methods, such as nature-based solutions, direct air capture, or enhanced weathering. GGR is considered necessary to achieve net-zero emissions and limit global warming to well below 2°C above pre-industrial levels.
See also: CDR - Carbon dioxide removal, Negative emissions, Net Zero Emissions
Greenhouse gases: Gases in Earth's atmosphere that absorb and re-emit infrared radiation, trapping heat and causing the greenhouse effect. The primary greenhouse gases are water vapor, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and ozone (O3). Human activities, such as burning fossil fuels and land-use changes, have significantly increased the atmospheric concentrations of greenhouse gases, leading to global warming.
See also: Global warming, Anthropogenic CO2, Climate change
Greenhouse Gas Inventory: A comprehensive accounting of all greenhouse gas emissions and removals within a specific geographic area or organization over a set period. GHG inventories are essential for tracking progress towards climate targets and identifying key sources of emissions.
Greenwashing: The practice of making false, misleading, or unsubstantiated claims about the environmental benefits of a product, service, or organization. Greenwashing can undermine the credibility of genuine sustainability efforts and create confusion among consumers and stakeholders.
See also: Carbon footprint, Life cycle emissions, Moral hazard
Hard-to-abate sector: Industries or processes where reducing greenhouse gas emissions is particularly challenging due to technical, economic, or practical limitations. Examples include heavy industry (e.g., cement, steel, chemicals), long-distance transportation (e.g., aviation, shipping), and high-temperature heat production. Decarbonizing hard-to-abate sectors often requires the development and deployment of advanced technologies, such as carbon capture and storage, hydrogen, or electrification.
See also: Decarbonization, carbon capture
Inflation Reduction Act: A United States federal law enacted in August 2022 that includes significant provisions for climate change mitigation, healthcare, and deficit reduction. The Act allocates approximately $369 billion for energy security and climate change programs over the next ten years, making it the largest investment in climate action in U.S. history.
See also: 45Q Tax Credit, Renewable energy, Decarbonization, EU Carbon Border Adjustment Mechanism
Land-use change: The modification of the Earth's surface by human activities, such as deforestation, urbanization, agricultural expansion, or afforestation. Land-use change can significantly impact the global carbon cycle by altering the amount of carbon stored in vegetation and soils, as well as the exchange of carbon between the land and the atmosphere. For example, deforestation releases stored carbon into the atmosphere, while afforestation and reforestation can enhance carbon sequestration. Understanding and managing land-use change is crucial for mitigating climate change and achieving sustainable development goals.
See also: Carbon cycle, Deforestation, afforestation, Reforestation, Soil carbon storage
Life cycle emissions: The total greenhouse gas emissions associated with a product or service throughout its entire life cycle, from raw material extraction to end-of-life disposal. Life cycle emissions provide a comprehensive assessment of the climate impact of a product or service and can help identify opportunities for emission reductions.
See also: Carbon footprint, ,
Lifecycle emissions: The total amount of greenhouse gas emissions generated throughout the entire lifecycle of a product or service, from resource extraction to production, use, and disposal. Lifecycle emissions provide a comprehensive view of the environmental impact of a product or service and can help identify opportunities for reducing emissions at different stages.
See also: Life cycle emissions, Carbon footprint
Long-term carbon cycle: The exchange of carbon between the atmosphere, oceans, and geologic reservoirs over timescales of thousands to millions of years. The long-term carbon cycle is driven by slow processes, such as rock weathering, volcanic activity, and tectonic uplift, and plays a crucial role in regulating Earth's climate over geologic timescales.
See also: Carbon cycle, Geological Storage
Mineral carbonation: A process that involves the reaction of carbon dioxide (CO2) with metal oxide-bearing rocks, such as silicates or hydroxides, to form stable carbonate minerals. Mineral carbonation is a natural process that occurs slowly over geological timescales, but it can be accelerated through engineered methods to permanently sequester CO2 from the atmosphere or industrial emissions. The resulting carbonate minerals, such as calcite or magnesite, are environmentally benign and can be used in various applications, such as construction materials or soil amendments. Mineral carbonation is a promising approach for long-term carbon storage and can contribute to climate change mitigation efforts.
See also: Carbon sequestration, Enhanced weathering/mineralization,Permanent sequestration
Mitigation: Actions taken to reduce greenhouse gas emissions and limit the extent of climate change. Mitigation measures can include adopting low-carbon technologies, improving energy efficiency, and promoting sustainable land use practices, among others.
See also: Decarbonization,
Moral hazard is the risk that people or organizations may act less responsibly when they believe a safety net or solution will mitigate potential consequences. In the context of carbon capture and storage (CCS) and carbon dioxide removal (CDR), this refers to concerns that reliance on these technologies might reduce efforts to cut emissions at their source, delaying transitions to renewable energy and other critical climate actions.
See also: Greenwashing
MRV – monitoring, reporting and verification: A framework for tracking, documenting, and assessing greenhouse gas emissions, emission reductions, and removals. MRV is essential for ensuring the transparency, accuracy, and comparability of climate action and is a key component of international climate agreements, such as the Paris Agreement.
See also: Carbon accounting,
Nationally Determined Contributions (NDCs): The climate action plans submitted by countries under the Paris Agreement, outlining their commitments to reduce greenhouse gas emissions and adapt to the impacts of climate change. NDCs are the primary means by which countries communicate their contributions to the global effort to limit global warming to well below 2°C above pre-industrial levels.
See also: Paris Agreement,
Nature-based solutions: Actions that protect, sustainably manage, or restore natural ecosystems to address societal challenges, such as climate change, while providing benefits for both human well-being and biodiversity. Nature-based solutions for climate change mitigation include afforestation, reforestation, wetland restoration, and soil carbon sequestration.
See also: afforestation, reforestation, blue carbon, soil carbon sequestration
Negative emissions: The removal of greenhouse gases, particularly CO2, from the atmosphere through deliberate human activities, such as afforestation, bioenergy with carbon capture and storage (BECCS), or direct air capture. Achieving negative emissions is considered necessary to offset hard-to-abate emissions and limit global warming to well below 2°C above pre-industrial levels.
See also: CDR - carbon dioxide removal, BECCS, DAC - direct air capture
Negative emissions technologies (NETs): A range of methods and technologies designed to remove CO2 from the atmosphere, such as direct air capture, bioenergy with carbon capture and storage (BECCS), and enhanced weathering. NETs are considered essential for achieving net-zero emissions and limiting global warming, as they can offset hard-to-abate emissions and potentially enable net-negative emissions.
See also: CDR - carbon dioxide removal, BECCS, DAC - direct air capture
Net negative emissions: A situation in which the total amount of greenhouse gases removed from the atmosphere through deliberate human activities exceeds the total amount of greenhouse gases emitted. Achieving net negative emissions may be necessary in the long term to reverse the impacts of climate change and stabilize the Earth's climate system.
See also: negative emissions, CDR - carbon dioxide removal, net zero emissions
Net zero: A state in which the amount of greenhouse gases emitted is balanced by the amount removed from the atmosphere through natural processes or deliberate human activities. Achieving net-zero emissions is necessary to stabilize the Earth's climate and limit the impacts of climate change, and requires a combination of emission reductions and carbon removal strategies.
See also: net zero Emissions, CDR - carbon dioxide removal
Net zero emissions by 2050 (NZE) scenario: A comprehensive pathway outlined by the International Energy Agency (IEA) that details the global energy sector's transition to achieve net-zero CO2 emissions by 2050. This scenario maps out a way to limit global temperature rise to 1.5°C above pre-industrial levels, in line with the Paris Agreement goals. The NZE Scenario involves rapid and far-reaching transitions across all sectors of the economy, including accelerated deployment of clean energy technologies, energy efficiency improvements, and behavioral changes.
See also: net zero emissions, Paris Agreement, decarbonization,
Net Zero Emissions: A state in which the total amount of greenhouse gases emitted is balanced by the total amount removed from the atmosphere through natural processes or deliberate human activities. Achieving net-zero emissions is a key goal of international climate agreements, such as the Paris Agreement, and is necessary to limit global warming to well below 2°C above pre-industrial levels.
See also: net zero, CDR - carbon dioxide removal
Ocean alkalinization: A proposed method for removing CO2 from the atmosphere by increasing the alkalinity of ocean waters through the addition of alkaline minerals, such as olivine or calcium carbonate. Ocean alkalinization enhances the ocean's natural carbon uptake and storage capacity, but its long-term effects on marine ecosystems and biogeochemical cycles are not yet fully understood.
See also: enhanced weathering/mineralization, ocean carbon cycle, CDR - carbon dioxide removal
Ocean carbon cycle: The process by which carbon is exchanged between the atmosphere, ocean surface, and deep ocean. The ocean absorbs CO2 from the atmosphere through physical and biological processes, such as air-sea gas exchange, dissolution, and photosynthesis by marine phytoplankton. The absorbed CO2 is then transported to the deep ocean through ocean circulation and the biological pump, where it can be stored for centuries to millennia. The ocean carbon cycle plays a crucial role in regulating atmospheric CO2 concentrations and the Earth's climate.
See also: carbon cycle, CO2 absorption
Ocean fertilization: A proposed method for removing CO2 from the atmosphere by stimulating the growth of marine phytoplankton through the addition of nutrients, such as iron or nitrogen, to ocean waters. Phytoplankton absorb CO2 through photosynthesis and can potentially sequester carbon in the deep ocean when they die and sink. However, the effectiveness and potential ecological impacts of ocean fertilization are not yet fully understood.
See also: ocean carbon cycle, CDR - carbon dioxide removal
Oxyfuel combustion: A combustion process in which fuel is burned in an atmosphere of pure oxygen instead of air, resulting in a flue gas composed mainly of CO2 and water vapor. This high-concentration CO2 stream can be easily separated and captured for storage or utilization, making oxyfuel combustion a promising technology for carbon capture and storage (CCS) in power generation and industrial processes.
See also: CCS - carbon capture and storage, post-combustion, pre-combustion
Paris Agreement: An international treaty adopted in 2015 under the United Nations Framework Convention on Climate Change (UNFCCC), in which countries agreed to work together to limit global warming to well below 2°C above pre-industrial levels, and to pursue efforts to limit the increase to 1.5°C. The Paris Agreement requires countries to submit and regularly update their Nationally Determined Contributions (NDCs) to reduce greenhouse gas emissions and adapt to the impacts of climate change.
See also: Nationally Determined Contributions (NDCs), climate change mitigation,
Pathway to net zero: A roadmap or plan outlining the steps and strategies needed to reduce greenhouse gas emissions and achieve net-zero emissions bya specific target date, typically by mid-century. Pathways to net zero often involve a combination of emission reduction measures, such as transitioning to clean energy, improving energy efficiency, and adopting sustainable land use practices, as well as carbon removal strategies, such as afforestation, carbon capture and storage, and direct air capture.
See also: net zero emissions, CDR - carbon dioxide removal
Permanent sequestration: The long-term storage of carbon in a manner that prevents its release back into the atmosphere for hundreds to thousands of years. Permanent sequestration is a key requirement for the effectiveness of carbon capture and storage (CCS) and other carbon removal strategies in mitigating climate change. Examples of permanent sequestration include geological storage, mineralization, and deep ocean storage.
See also: carbon sequestration, geological Storage, mineral carbonation
Photosynthesis: The process by which plants and other photosynthetic organisms convert sunlight, water, and carbon dioxide (CO2) into organic compounds, such as glucose, while releasing oxygen as a byproduct. Photosynthesis is the primary mechanism by which CO2 is removed from the atmosphere and converted into biomass, making it a crucial process in the global carbon cycle and climate regulation.
See also: carbon cycle, biomass, carbon sequestration
Pipeline transport: The process of transporting captured CO2 from its source to a storage site via a network of pipelines. Pipeline transport is considered the most cost-effective and efficient method for transporting large volumes of CO2 over long distances, especially when compared to other options such as trucks or ships. The development of extensive CO2 pipeline networks is crucial for the large-scale deployment of carbon capture and storage (CCS) technologies.
See also: CO2 transportation, CCS - carbon capture and storage, carbon hub
Point source emissions: Emissions of greenhouse gases or other pollutants from a single, identifiable source, such as a power plant, industrial facility, or exhaust stack. Point source emissions are easier to monitor, control, and capture compared to diffuse or area sources, making them a primary target for emission reduction and carbon capture technologies.
See also: carbon capture, CCS - carbon capture and storage,
Post-combustion: A carbon capture process that separates CO2 from the flue gases produced by the combustion of fossil fuels or biomass in power plants or industrial processes. Post-combustion capture typically involves the use of chemical solvents, such as amines, to absorb CO2 from the flue gas stream, which is then released and compressed for storage or utilization.
See also: carbon capture, amine absorption, CCS - carbon capture and storage
Pre-combustion carbon capture: A carbon capture process that involves converting fossil fuels into a mixture of hydrogen and CO2 before combustion, typically through gasification or reforming. The CO2 can then be easily separated and captured, while the hydrogen is used as a clean fuel for power generation or other applications. Pre-combustion capture is more efficient than post-combustion capture but requires significant modifications to existing power plants and industrial processes.
See also: carbon capture, hydrogen production, CCS - carbon capture and storage
Process emissions: Greenhouse gas emissions that are released as a byproduct of industrial processes, such as cement production, steel manufacturing, or chemical processing, rather than from the combustion of fossil fuels for energy. Process emissions are inherent to the chemical reactions or physical processes involved in these industries and can be difficult to abate without fundamental changes to the production methods or the deployment of carbon capture technologies. An example of process emissions is the generation of CO2 in cement manufacture from the chemical transformation of limestone (calcium carbonate) into lime (calcium oxide) during the calcination process. Reducing process emissions is a key challenge in decarbonizing hard-to-abate sectors and achieving net-zero emissions targets.
See also: combustion emissions, hard-to-abate sector, carbon capture,
Reforestation: The process of replanting trees in areas where forests have been previously cleared or degraded. Reforestation helps to restore forest ecosystems, enhance biodiversity, and increase carbon sequestration, as growing trees absorb CO2 from the atmosphere and store it in their biomass and soils. Reforestation is a key nature-based solution for mitigating climate change and achieving negative emissions.
See also: afforestation, nature-based solutions, carbon sequestration
Renewable energy: Energy derived from natural sources that are replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat. Renewable energy technologies include solar power, wind power, hydroelectricity, geothermal energy, and bioenergy. Unlike fossil fuels, renewable energy sources have a much lower environmental impact and do not contribute significantly to greenhouse gas emissions. Increasing the adoption of renewable energy is a key strategy for decarbonizing the energy sector and mitigating climate change. [See also: Decarbonization, Fossil fuels]
Respiration: The process by which living organisms, including plants, animals, and microorganisms, convert organic compounds, such as glucose, into energy for growth and maintenance, releasing CO2 as a byproduct. Respiration is the reverse process of photosynthesis and plays a crucial role in the global carbon cycle by returning CO2 to the atmosphere.
See also: photosynthesis, Carbon cycle,
Retrofitting: The process of modifying existing industrial facilities, power plants, or buildings to improve their energy efficiency, reduce emissions, or incorporate carbon capture and storage (CCS) technologies. Retrofitting is often more cost-effective than building new low-carbon infrastructure and can play a significant role in reducing greenhouse gas emissions from hard-to-abate sectors.
See also: CCS - Carbon Capture and Storage, Hard-to-abate sector
Saline aquifers: Deep, porous rock formations that are saturated with saline (salty) water, often located below freshwater aquifers. Saline aquifers have a large potential capacity for long-term CO2 Storage, as the injected CO2 dissolves in the brine and eventually forms stable carbonate minerals. Saline aquifers are a key target for geological carbon storage due to their widespread occurrence and low risk of leakage.
See also: Geological Storage, Mineral carbonation, CO2 Storage
Scaling up: The process of increasing the size, capacity, or deployment of a technology or solution to achieve significant impact and economies of scale. Scaling up low-carbon technologies, such as renewable energy, energy storage, and carbon capture and storage, is essential for achieving rapid emission reductions and limiting global warming. Scaling up also involves addressing financial, technical, and social barriers to widespread adoption.
See also: ,
Sequestration potential: The maximum amount of carbon that can be captured and stored by a particular carbon sequestration method or reservoir, such as a forest, soil, or geological formation. Sequestration potential is determined by various factors, including the size of the reservoir, the rate of carbon uptake or injection, and the stability of the stored carbon over time. Understanding sequestration potential is crucial for prioritizing and optimizing carbon removal strategies.
See also: carbon sequestration, ,
Short-term carbon cycle: The exchange of carbon between the atmosphere, oceans, terrestrial biosphere, and soil on timescales ranging from days to centuries. The short-term carbon cycle is primarily driven by biological processes, such as photosynthesis, respiration, and decomposition, and is sensitive to human activities like land-use change and fossil fuel combustion. Understanding the short-term carbon cycle is crucial for predicting the near-term impacts of carbon dioxide emissions on the Earth's climate system.
See also: carbon cycle, photosynthesis, respiration, Land-use change
Soil carbon sequestration: The process of capturing and storing atmospheric carbon in soils through various land management practices, such as conservation tillage, cover cropping, and agroforestry. Soil carbon sequestration enhances soil health, fertility, and water retention while contributing to climate change mitigation by removing CO2 from the atmosphere.
See also: carbon Sequestration, soil carbon storage,
Soil carbon storage: The amount of carbon stored in soils in the form of organic matter, such as decomposed plant and animal residues, and inorganic carbon, such as carbonates. Soil carbon storage is a significant component of the global carbon cycle and can be enhanced through various land management practices, helping to mitigate climate change.
See also: soil carbon sequestration, carbon cycle, land-use change
Verified Carbon Standard (VCS): A widely recognized certification program that provides standards for the creation, validation, and verification of carbon offset projects. The VCS ensures that carbon credits represent real, measurable, and permanent emissions reductions.
Voluntary carbon market: A market in which individuals, companies, or organizations voluntarily purchase carbon credits to offset their greenhouse gas emissions. Voluntary Carbon Markets operate independently from compliance markets and enable the financing of emission reduction and carbon removal projects that may not be covered by mandatory regulations.
See also: carbon market, carbon credit, carbon offset, compliance market