Climate & air pollution
Methane Emissions
Releases of methane — a potent but short-lived greenhouse gas — mainly from agriculture (≈40%), fossil fuels (≈35%) and waste (≈20%), responsible for about a third of today's warming.
Definition
Methane emissions are releases of methane (CH4), the primary component of natural gas, a greenhouse gas with a lifetime of about a decade and a global warming potential around 80 times that of CO2 over 20 years. Human-caused emissions come chiefly from agriculture (livestock, manure, rice), fossil fuel production and distribution (including leakage), and landfills and wastewater. Methane is responsible for roughly a third of the warming experienced to date.
References
potency (~80x over 20 years), one-third of warming, sector shares, abatement potential
intensity metric definition and reporting frameworks
Overview
What it means
Because methane is short-lived, cutting emissions delivers rapid climate benefit; it also reduces ground-level ozone, which causes about a million premature deaths annually and damages crops. Methane intensity — emissions per unit of output (e. g. , per barrel of oil equivalent or as a share of gas throughput) — is the standard performance metric for oil and gas operators, reported under frameworks such as OGMP 2. 0.
Methane leakage from gas infrastructure is a major, often underestimated source.
How it is used
National inventories report methane by sector using IPCC methods; satellite detection and measurement campaigns increasingly expose super-emitters; regulators set performance standards and fees on excess emissions.
Why it matters
Methane cuts of 30–60% below 2020 levels by 2030 are required in least-cost 1. 5°C pathways, and much fossil-sector abatement is available at negative or low cost — making methane the fastest lever to slow near-term warming. **Note:** In-batch merges: 1739 "Methane Intensity" and 1740 "Methane leakage" → this entry.
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