Greenhouse Gas Science & Metrics
What is Carbon Dioxide (CO₂)?
Carbon dioxide (CO₂) is the primary greenhouse gas emitted from burning fossil fuels, deforestation, and industrial processes, serving as the baseline against which all other greenhouse gases are measured.
Sentinel Earth specializes in GHG accounting and the investment and implementation of projects that aim to remove, sequester, or avoid GHG emissions under various standards and schemes including Verra, Gold Standard, Puro.earth, and Article 6.2 of the Paris Agreement.
What is Carbon Dioxide Equivalent (CO₂e)?
Carbon dioxide equivalent (CO₂e) is the standard unit that expresses the warming impact of all greenhouse gases in terms of the equivalent amount of carbon dioxide, enabling comparison across different gases using global warming potential.
For example, Sentinel Earth's Dark Earth biochar project in Singapore removes approximately 9,000 tCO₂e per year, and Seeds of Recovery in Ukraine sequesters around 90,000 tCO₂e per year through regenerative agriculture. Our Azure Road insetting project in China helps corporate partners reduce their Scope 3 emissions by around 12,000 tCO₂e per year through electric truck fleet transition.
What is Greenhouse Gas (GHG)?
Greenhouse gases (GHGs) are atmospheric gases that trap heat from the sun, including carbon dioxide, methane, nitrous oxide, and fluorinated gases, causing the greenhouse effect that leads to global warming and climate change.
Sentinel Earth specializes in GHG accounting and the investment and implementation of projects that aim to remove, sequester, or avoid GHG emissions under various standards and schemes including Verra, Gold Standard, Puro.earth, and Article 6.2 of the Paris Agreement.
What is Methane (CH₄)?
Methane (CH₄) is a potent greenhouse gas with 28-84 times the warming potential of carbon dioxide over different time periods, emitted from agriculture, fossil fuel production, waste decomposition, and wetlands.
Sentinel Earth develops methane capture and destruction projects, including a project in Nigeria that captures methane that would otherwise be flared and uses it to power data centres in a highly grid-unstable country, reducing emissions while generating high-integrity carbon credits.
What is Nitrous Oxide (N₂O)?
Nitrous oxide (N₂O) is a long-lasting greenhouse gas with 265-298 times the warming potential of carbon dioxide, primarily emitted from agricultural soils, fertilizer production and use, and industrial processes.
Sentinel Earth's agricultural carbon projects, such as Seeds of Recovery in Ukraine, reduce nitrous oxide emissions through improved nutrient management practices, quantifying N₂O reductions alongside soil carbon sequestration for comprehensive climate benefits.
What is Global Warming Potential (GWP)?
Global warming potential (GWP) measures how much heat a greenhouse gas traps in the atmosphere relative to carbon dioxide over a specific time period (typically 100 years), enabling comparison of different gases using CO₂e.
Some gases have very high GWP, such as hydrofluorocarbons (HFCs) used in refrigeration and air conditioning, which can have GWPs thousands of times greater than CO₂. Sentinel Earth implements HFC collection and destruction projects worldwide, delivering measurable positive climate impact.
What is Metric Tonne?
A metric tonne (also spelled metric ton) is a unit of mass equal to 1,000 kilograms or approximately 2,204 pounds; in carbon markets, one carbon credit represents one metric tonne of CO₂e reduced or removed.
Sentinel Earth's projects deliver measurable climate impact in metric tonnes of CO₂e: Dark Earth in Singapore removes approximately 9,000 tonnes per year through biochar carbon removal, Seeds of Recovery in Ukraine sequesters around 90,000 tonnes per year through regenerative agriculture, and Azure Road in China avoids around 12,000 tonnes per year through electric truck fleet insetting.