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Reference Library

Glossary of Carbon & Sustainability Terms

Plain-English definitions for the terminology used across GHG accounting, Climate Active certification, AASB S2 reporting, Life Cycle Assessment, Environmental Product Declarations and net zero target setting.

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2026
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Australian Standards & Regulatory Context
Mandatory Climate Reporting & GHG Inventories

AASB S2 Reporting, Climate Active Certification (Organisation) & GHG Emissions Inventories

Terms covering the mandatory AASB S2 climate-related financial disclosure standard, Australia’s Climate Active carbon neutral certification for organisations, and corporate greenhouse gas inventories.

AASB S2 Reporting

AASB S2
Australia’s mandatory climate-related financial disclosure standard, made by the Australian Accounting Standards Board and based on the international IFRS S2 standard, requiring disclosure of governance, strategy, risk management, and metrics and targets.
Australian Sustainability Reporting Standards (ASRS)
The suite of standards, including AASB S1 and AASB S2, developed by the AASB to give effect to Australia’s sustainability and climate-related reporting requirements.
Capital Deployment
A cross-industry metric requiring disclosure of the amount of capital expenditure, financing or investment an entity has directed towards climate-related risks and opportunities.
Climate Resilience
An entity’s capacity to adjust to climate-related changes and uncertainties, assessed under AASB S2 using scenario analysis.
Climate-related Physical Risk
Risk arising from the physical effects of climate change, either sudden events like storms and floods (acute) or longer-term shifts like changing rainfall patterns (chronic).
Climate-related Risks and Opportunities
The potential negative and positive effects of climate change on an entity, covering both physical risks and transition risks.
Climate-related Transition Plan
An aspect of an entity’s overall strategy setting out its targets, actions, and resource allocation for transitioning toward a lower-carbon economy.
Climate-related Transition Risk
Risk arising from the shift to a lower-carbon economy, including policy, legal, technology, market, and reputational risks.
Corporations Act 2001
The Australian legislation that sets out which entities must comply with AASB S2 and specifies the staggered application dates for different classes of entity.
Cross-industry Metric Categories
The set of standard metrics AASB S2 requires beyond greenhouse gas emissions, including transition risk exposure, physical risk exposure, capital deployment, internal carbon pricing, and climate-linked remuneration.
Financed Emissions
The portion of a borrower’s or investee’s emissions attributed to an entity’s loans and investments, disclosed separately by entities in asset management, banking, or insurance.
General Purpose Financial Report (GPFR)
The report to which AASB S2 climate-related disclosures attach, providing information useful to investors, lenders, and creditors for resource allocation decisions.
Governance
The AASB S2 disclosure area covering how an entity’s board and management oversee climate-related risks and opportunities.
Group 1, Group 2, Group 3 Entities
The three phased categories of entities captured by Australia’s mandatory climate reporting regime, based on size or emissions profile, with staggered start dates from 2025 through 2027.
IFRS S2
The international climate-related disclosure standard issued by the International Sustainability Standards Board (ISSB), which forms the baseline that AASB S2 is built on, modified for the Australian legal and regulatory environment.
Impracticable
A requirement is impracticable when an entity cannot apply it after making every reasonable effort to do so, providing limited relief from certain AASB S2 requirements.
Interim Reporting
Climate-related disclosures provided at a reporting date other than an entity’s annual reporting date, typically more condensed and focused on new developments.
Internal Carbon Price
A price an entity applies internally to assess the financial implications of its emissions, used in decision-making such as investment appraisal, transfer pricing or scenario analysis.
International Sustainability Standards Board (ISSB)
The international standard-setting body responsible for developing IFRS S1 and IFRS S2, on which the Australian Sustainability Reporting Standards are based.
Latest International Agreement on Climate Change
A defined reference in AASB S2 to the Paris Agreement of December 2015, used as a benchmark for climate-related targets and scenario analysis.
Metrics and Targets
The AASB S2 disclosure area covering an entity’s greenhouse gas emissions, other climate-related metrics, and progress against any climate-related targets.
Not-for-Profit Entity Considerations
Modifications within AASB S2 recognising that the users and objectives of a not-for-profit entity’s general purpose financial report differ from those of a for-profit entity.
Primary Users
The existing and potential investors, lenders and other creditors that AASB S2 disclosures are prepared for, whose resource allocation decisions the information is intended to support.
Remuneration Metric
A cross-industry metric requiring disclosure of whether and how climate-related considerations are factored into executive remuneration, including the percentage linked to climate performance.
Risk Management
The AASB S2 disclosure area covering the processes an entity uses to identify, assess, and manage climate-related risks, and how these integrate with its overall risk management.
Scenario Analysis
A structured method for testing how an entity’s strategy would perform under different possible climate futures; Australian legislation requires testing against both a high-warming and a 1.5 degree-aligned scenario.
Sector-Neutral Standard
An approach to standard-setting, adopted by the AASB where practicable, ensuring similar transactions and events are treated consistently across entities regardless of their sector.
Statement of Compliance
A formal, unreserved declaration that an entity’s disclosures meet every requirement of AASB S2; the standard does not allow partial or qualified compliance claims.
Strategy
The AASB S2 disclosure area covering an entity’s identified climate risks and opportunities and their effect on its business model, financial position, and resilience.
Timeliness
An enhancing qualitative characteristic requiring that climate-related information be available to decision-makers in time to influence their decisions.
Transition Relief
Temporary reliefs available to an entity in the first year it applies AASB S2, such as not needing to disclose Scope 3 emissions or being able to continue an existing emissions measurement method.
Understandability
An enhancing qualitative characteristic requiring climate-related disclosures to be clear, concise and free of unnecessary boilerplate or duplication.
Verifiability
An enhancing qualitative characteristic meaning that independent, knowledgeable observers could reach consensus that a disclosure is a faithful representation.

Climate Active Certification (Organisation)

Approved Certifier
An entity approved by the Department to certify organisations, products and services, buildings, precincts or events as carbon neutral against the Climate Active standards, based on their sector expertise.
Australian Carbon Credit Unit (ACCU)
A tradeable unit issued by the Clean Energy Regulator representing one tonne of CO2 equivalent stored or avoided; Climate Active requires a minimum proportion of offsets to be ACCUs.
Cancellation
The retirement of a carbon credit or offset unit within a registry so it can no longer be sold or used again, attributed to the specific carbon neutral claim it supports.
Carbon Account
A measure of the carbon dioxide equivalent emissions attributable to an organisation, also known as a carbon footprint or emissions inventory, calculated according to the Organisation Standard’s principles.
Carbon Neutral
A state where an organisation’s measured emissions for a reporting period have been balanced by an equivalent quantity of eligible carbon offsets, generally after genuine reduction effort.
Carbon Neutral Standard for Organisations
The specific Climate Active standard setting out the boundary-setting, measurement, reduction, and offsetting requirements an organisation must meet to be certified carbon neutral at the entity level.
Certification Trade Mark
The Climate Active Carbon Neutral Certification Trade Mark, available under licence to organisations certified by the Australian Government to showcase their carbon neutrality.
Climate Active
Australia’s government-backed voluntary carbon neutral certification program, administered by the Department of Climate Change, Energy, the Environment and Water.
Conservative Approach
An approach to estimation that reduces the risk of understating emissions in a carbon account, favoured wherever uncertainty is high.
Control Approach (Climate Active)
The method used to determine which emissions are under an organisation’s direct control for certification purposes, based on financial control, operational control, or equity share.
Eligible Offset Unit
A carbon credit that meets Climate Active’s minimum quality requirements, including ACCUs and approved international units such as Gold Standard or Verra credits.
Emissions Boundary
The coverage and extent of an organisation’s carbon account, established by identifying which emissions sources are included or excluded and why.
Emissions Reduction Activity
Genuine efforts to reduce emissions, such as energy efficiency upgrades or renewable energy procurement, that Climate Active expects an organisation to demonstrate before offsetting residual emissions.
Emissions Reduction Strategy
An organisation’s documented plan identifying the emissions reduction measures it will undertake over a specified timeframe, required to maintain a Climate Active carbon neutral claim.
Forward Offsetting
An offsetting approach where an organisation estimates its emissions for the coming reporting year and cancels that number of eligible offset units at the start of the year, followed by an annual true-up.
Licence Agreement
The formal agreement an organisation signs with Climate Active governing use of the carbon neutral trade mark and ongoing compliance with the standard.
National Greenhouse Accounts Factors (NGA Factors)
The Australian Government’s annual publication of emission factors, covering Scope 1 and 2 sources and Scope 3 factors for waste, fuels and electricity, used as the default reference for Climate Active carbon accounts.
Non-Quantified Emissions
Relevant emissions sources that remain within the emissions boundary but are not measured in the carbon account, because doing so would not be technically feasible, practicable or cost effective.
Notice of Certification
The formal letter from the Department confirming that an organisation’s application for Climate Active certification has been successful.
Notice of Continuing Certification
The formal letter from the Department confirming that an organisation’s annual obligations for maintaining Climate Active certification have been met.
Offsetting in Arrears
An offsetting approach where an organisation cancels eligible offset units for a claim period only after that period has finished.
Organisational Boundary (Climate Active)
The defined scope of entities and operations included in a Climate Active certification, set using an operational control, financial control, or equity share basis.
Public Disclosure Statement
The published document accompanying a Climate Active certification that discloses an organisation’s emissions inventory, boundary, and the offset units used, giving the claim public transparency.
Recertification
The annual process of updating an organisation’s emissions inventory and offset position to maintain carbon neutral certification for a new reporting period.
Relevance
The principle ensuring an organisation’s carbon account appropriately reflects its emissions and meets the decision-making needs of internal and external users.
Relevance Test
The qualitative test used to determine whether an emissions source should be included in an organisation’s emissions boundary, based on criteria such as materiality, risk exposure and stakeholder expectations.
Residual Emissions
The emissions remaining after an organisation has applied genuine reduction measures, which are then compensated for through offsetting to achieve carbon neutral status.
Responsible Entity
The organisation or authorised individual that takes responsibility for making a carbon neutral claim or seeking carbon neutral certification, including meeting all reporting and offsetting obligations.
Technical Assessment
An independent review of the methodology behind an organisation’s carbon neutral claim, required at initial certification and periodically thereafter.
True-Up
The annual reconciliation process confirming that the number of offset units cancelled is at least equal to an organisation’s actual emissions, used under the forward offsetting approach.
Uplift Factor
A factor applied to increase an estimated emissions figure, used to mitigate the risk of underestimating emissions where data is incomplete.
Vintage
The year in which an offset unit’s underlying emissions reduction or removal occurred, used to assess the currency and eligibility of the unit.

GHG Emissions Inventories

Activity Data
The raw quantitative data an emission factor is applied to, such as fuel consumed, distance travelled, or electricity used.
Additionality
A requirement that an emissions reduction or removal used as an offset would not have happened anyway in the ordinary course of events, and has not been claimed elsewhere.
Assurance
The level of confidence provided by a verifier or auditor about the accuracy and completeness of reported emissions data, ranging from limited to reasonable assurance.
Average-Data Method
A Scope 3 calculation approach that estimates emissions using industry-average emission factors applied to activity data.
Base Year
A specific historical year (or average of years) against which an organisation’s emissions are tracked over time, used to measure progress on reduction targets.
Base Year Recalculation
Adjusting the base year emissions figure to reflect a significant structural change (such as an acquisition or divestment) or a change in calculation methodology, so that year-on-year comparisons remain meaningful.
Biogenic Emissions
Carbon dioxide emissions from the combustion or decomposition of biologically based materials, such as biofuels, which are typically reported separately from other CO2 emissions.
Carbon Credit
A tradeable unit representing a verified reduction or removal of one tonne of CO2 equivalent, issued by a recognised crediting program.
Carbon Footprint
A commonly used term for the total greenhouse gas emissions associated with an organisation, product, service or activity, usually expressed in CO2 equivalent.
CO2 Equivalent (CO2e)
The standard unit for comparing the warming effect of different greenhouse gases, expressed relative to the warming effect of one unit of carbon dioxide.
Contractual Instrument
An agreement, such as a power purchase agreement or a renewable energy certificate, that conveys specific claims about the source or attributes of purchased energy, used to support market-based Scope 2 reporting.
Direct Emissions
Emissions from sources owned or controlled by the reporting organisation (equivalent to Scope 1).
Double Counting
When the same emissions or emissions reduction is claimed by more than one organisation or counted more than once within an inventory.
Downstream Emissions
Scope 3 emissions associated with sold goods and services, occurring after they leave the organisation’s control.
Emission Factor
A figure used to convert a unit of activity, such as litres of fuel or kilowatt-hours of electricity, into a quantity of greenhouse gas emissions.
Emissions Intensity
A metric expressing greenhouse gas emissions relative to a business measure, such as revenue, floor area or units produced, allowing comparison of performance over time or between organisations.
Emissions Reduction Target
A quantified commitment to reduce greenhouse gas emissions by a defined amount over a defined timeframe, which may be absolute or intensity-based.
Equity Share Approach
A consolidation method where an organisation accounts for emissions in proportion to its percentage economic ownership of an operation.
Financial Control Approach
A consolidation method where an organisation accounts for 100% of emissions from operations it has the ability to direct financially and operationally for economic benefit.
GHG Inventory
A quantified list of an organisation’s greenhouse gas emissions and the sources they come from, covering a defined reporting period and boundary.
GHG Offset
A discrete emissions reduction achieved elsewhere and used to compensate for an organisation’s own emissions, typically measured against a baseline of what would have happened without the reduction activity.
GHG Program
An external scheme, whether voluntary or mandatory, that sets rules for how organisations measure, report or manage their greenhouse gas emissions, such as Australia’s National Greenhouse and Energy Reporting Scheme.
GHG Protocol
The most widely used international accounting framework for measuring and managing greenhouse gas emissions, made up of a family of standards covering corporate inventories, project accounting, value chain (Scope 3) emissions and product life cycles.
GHG Sink
A process, activity or mechanism that removes a greenhouse gas from the atmosphere, such as a forest or geological storage site.
GHG Source
A physical unit or process that releases a greenhouse gas into the atmosphere, such as a boiler, vehicle or industrial process.
Global Warming Potential (GWP)
A factor describing how much warming impact one unit of a given greenhouse gas has relative to one unit of CO2, used to convert other gases into CO2 equivalent, typically drawn from the latest IPCC assessment.
Greenhouse Gases (GHGs)
The atmospheric gases responsible for trapping heat and driving climate change. The Kyoto Protocol lists seven gases: carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulphur hexafluoride (SF6) and nitrogen trifluoride (NF3).
Hybrid Method
A Scope 3 calculation approach that combines primary supplier data with secondary or estimated data where primary data is unavailable.
Indirect Emissions
Emissions that result from an organisation’s activities but occur at sources owned or controlled by another entity (equivalent to Scope 2 and Scope 3).
Leakage
An unintended increase in emissions outside the boundary of an offset project that offsets some or all of the reduction the project claims to achieve.
Location-Based Method
A way of calculating Scope 2 emissions using the average emissions intensity of the grid an organisation is physically connected to, regardless of any renewable energy contracts held.
Market-Based Method
A way of calculating Scope 2 emissions based on the specific electricity products an organisation has contractually chosen, such as a power purchase agreement or renewable energy certificates.
Materiality
A concept used to judge whether an error, omission, or estimate is significant enough that it could reasonably affect a user’s understanding of, or decisions based on, the inventory.
Net Zero
A state in which any remaining greenhouse gas emissions are balanced by an equivalent amount of removals from the atmosphere, typically after deep reductions have been achieved.
Operational Boundary
The scope of direct and indirect emissions associated with operations once the organisational boundary has been set, defined by classifying emissions into Scope 1, 2 and 3.
Operational Control Approach
A consolidation method where an organisation accounts for 100% of emissions from operations it has the full authority to direct, regardless of ownership share.
Organisational Boundary
The line that determines which operations, entities, or facilities are included in an organisation’s emissions inventory, set using either an equity share or a control approach.
Permanence
A requirement that an emissions reduction represented by an offset is durable and will not be reversed, particularly relevant to carbon stored in vegetation or soil.
Power Purchase Agreement (PPA)
A contract between an energy buyer and generator, often for renewable electricity, that can be used as evidence for market-based Scope 2 emissions accounting.
Primary Data
Data collected directly from a specific activity within an organisation’s own operations or value chain, such as a supplier’s actual production figures.
Proxy Data
Data from a similar activity or process used as a stand-in when primary data isn’t available, without being adjusted to better represent the actual activity.
Recalculation Policy
An organisation’s documented rules for when and how it will restate historical emissions data, ensuring recalculations are applied consistently over time.
Removal
The act of taking a greenhouse gas out of the atmosphere and storing it, through biological or technological means.
Renewable Energy Certificate (REC)
A tradeable certificate representing the environmental attributes of one unit of renewable electricity generation, used to substantiate market-based emissions claims.
Reporting Period
The defined span of time, usually 12 months, over which an organisation’s emissions are measured and reported.
Science Based Target
An emissions reduction target that is independently assessed as consistent with the level of decarbonisation needed to limit global warming in line with the Paris Agreement.
Scope 1 Emissions
Direct emissions from sources an organisation owns or controls, such as fuel burned in company vehicles, on-site boilers, or industrial processes.
Scope 2 Emissions
Indirect emissions from the generation of purchased electricity, steam, heating or cooling that an organisation consumes. The emissions physically occur at the power station, not on site.
Scope 3 Categories
The 15 standard categories used to organise Scope 3 emissions, spanning 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 Emissions
All other indirect emissions that occur in an organisation’s value chain, both upstream (suppliers, purchased goods, business travel) and downstream (product use, end-of-life disposal), across 15 defined categories.
Secondary Data
Data not obtained directly from an organisation’s own value chain activities, often sourced from industry averages, government statistics or published databases.
Sequestration
The capture and long-term storage of atmospheric carbon dioxide, whether through biological processes such as tree growth or geological processes such as underground storage.
Spend-Based Method
A Scope 3 calculation approach that estimates emissions by applying economic input-output emission factors to the amount spent on goods or services.
Supplier-Specific Method
A Scope 3 calculation approach that uses emissions data provided directly by a supplier for the specific goods or services purchased.
Uncertainty
The lack of precision in an emissions figure arising from data quality, estimation methods or measurement limitations, which should be disclosed and managed conservatively.
Upstream Emissions
Scope 3 emissions associated with purchased or acquired goods and services, occurring before they enter the organisation’s own operations.
Value Chain
The full range of an organisation’s activities, resources and relationships, from raw material sourcing through to the use and end-of-life of its products or services.
Verification
An independent assessment, typically by a third party, of whether a GHG inventory has been prepared accurately and in accordance with the relevant standard.