A
Absorption
The process where CO₂ is taken up by natural systems like forests or oceans, or by engineered materials.
Afforestation
Planting trees on land that hasn’t had forests historically, helping absorb CO₂ from the air.
B
Baseline Emissions
A starting point used to measure changes in CO₂ emissions over time.
Biogenic CO₂
Carbon dioxide naturally released from biological sources like plants and animals.
C
Carbon Dioxide (CO₂)
A colorless gas released by burning fossil fuels and breathing, and a major cause of global warming.
Carbon Capture and Storage (CCS)
Technology that captures CO₂ from industrial sources and stores it underground.
Carbon Credit
A permit that allows the emission of one tonne of CO₂; can be traded between companies or countries.
Carbon Dioxide Removal (CDR)
Ways to pull CO₂ out of the atmosphere, like direct air capture or planting trees.
D
Decarbonization
Cutting down CO₂ emissions from energy and industry by switching to cleaner methods.
Direct Air Capture (DAC)
Machines that pull CO₂ directly from the air for storage or use.
E
Emissions Factor
A number that shows how much CO₂ is released per unit of fuel used or product made.
Emissions Trading System (ETS)
A market system where companies buy and sell CO₂ emission allowances under a set limit.
Enhanced Weathering
Spreading minerals to absorb CO₂ from the air and lock it into rock.
F
Fossil Fuel
Energy sources like coal, oil, and gas that release ancient CO₂ when burned.
Flux
The rate at which CO₂ moves between the atmosphere, land, and oceans.
G
Global Warming Potential (GWP)
A measure of how much heat a gas traps compared to CO₂.
Greenhouse Gas (GHG)
Any gas, including CO₂, that traps heat in Earth’s atmosphere.
H
Human-Caused (Anthropogenic) Emissions
CO₂ emissions from human activities like driving, flying, or deforestation.
Hydroxide Sorbent
A chemical that reacts with CO₂ to remove it from gases, often used in carbon capture.
I
IPCC (Intergovernmental Panel on Climate Change)
The UN body that studies and reports on climate science and CO₂ impacts.
Infrared Absorption Bands
The wavelengths where CO₂ absorbs heat, contributing to the greenhouse effect.
J
Joule (J)
A unit of energy used to measure the energy involved in CO₂ processes.
K
Kyoto Protocol
A global agreement setting CO₂ emission targets for developed countries.
L
Life-Cycle Assessment (LCA)
A full analysis of CO₂ emissions from making, using, and disposing of a product.
LULUCF
Land use and forestry activities that affect CO₂ levels, tracked in climate reports.
M
Methane Oxidation
The process of methane (a potent GHG) turning into CO₂, especially in the atmosphere.
Mineral Carbonation
Turning CO₂ into solid rock by reacting it with minerals.
N
Net Zero
Balancing the amount of CO₂ released with the amount removed from the atmosphere.
Negative Emissions
Techniques that remove more CO₂ than they emit.
O
Ocean Acidification
Oceans absorbing CO₂, making them more acidic and affecting marine life.
Offset
A CO₂ reduction elsewhere used to balance out emissions from another source.
P
ppm (Parts Per Million)
A unit showing how much CO₂ is in the air; currently around 420 ppm.
Process Emissions
CO₂ released from industrial processes, not from burning fuel.
Q
Quota
A limit on how much CO₂ an entity is allowed to emit, often used in trading systems.
R
Radiative Forcing
The change in energy balance due to increased CO₂ in the atmosphere.
Relative Emission Reduction
How much CO₂ emissions have dropped compared to a starting point.
S
Sequestration
Long-term storage of CO₂ in forests, soils, or underground.
Sink
A natural or artificial system that absorbs more CO₂ than it releases.
T
Thermal Decarbonization
Switching to low-carbon heat sources in industries to cut CO₂ emissions.
Tonne of CO₂e
One metric tonne of CO₂ or another greenhouse gas, adjusted for its warming effect.
U
UEC (Unit Energy Consumption)
How much energy is used to make one unit of a product—used to assess CO₂ efficiency.
V
VAM (Ventilation Air Methane) Abatement
Capturing methane from mine ventilation systems to prevent it from becoming CO₂ in the air.
Volumetric Flow Rate
The speed at which gas flows, important in designing CO₂ capture systems.
W
Well-to-Wheel Analysis
Looks at all CO₂ emissions from fuel production to vehicle use.
X
X-bank Credits
Stored CO₂ allowances saved for future use under emissions trading programs.
Y
Yield Stress in Carbonate Membranes
A property of materials used to separate CO₂, influencing how well they work.
Z
Zero-Carbon Energy
Energy sources that don’t emit CO₂ when generating power, like wind or solar.