Editing Methane emissions (anthropogenic)

<!-- SIGNAL_EARTH_INFOBOX_START -->
{| class="wikitable" style="float:right; clear:right; margin:0 0 1em 1em; width:320px;"
|+ SIGNAL Earth Structured Data
|-
! Object type
| Damage Signal
|-
! SIGNAL Earth ID
| DS-00055
|-
! Observable type
| Methane emissions (anthropogenic)
|-
! Unit
| tonnes CH₄/yr (tonnes methane emitted per year)
|-
! Temporal structure
| Annual
|-
! Monitoring backbone
| UNFCCC inventories / national & facility reporting
|}
<!-- SIGNAL_EARTH_INFOBOX_END -->

{{SignalTerm|type=DS|id=DS-00055|label=Methane emissions (anthropogenic)}} refer to the release of methane gas into the atmosphere as a direct result of human activities. Methane (CH₄) is a potent greenhouse gas with a global warming potential significantly higher than carbon dioxide over a 20-year period. These emissions contribute to climate-system forcing and play a critical role in global climate dynamics. Understanding and quantifying anthropogenic methane emissions is essential for assessing human impacts on atmospheric composition and climate change.

Anthropogenic methane sources include activities such as fossil fuel extraction and use, agriculture (notably enteric fermentation in livestock and rice cultivation), waste management including landfills, and biomass burning. These emissions are distributed globally but vary regionally depending on industrial practices, agricultural intensity, and waste management approaches. Monitoring these emissions supports international climate agreements and informs mitigation strategies.

Within the broader context of atmospheric science and environmental monitoring, methane emissions are considered a pressure or stressor on the climate system. Their measurement and analysis contribute to understanding the drivers of climate change and the feedback mechanisms within the Earth system.

== Geographic / System Context ==
Methane emissions (anthropogenic) are a global phenomenon, occurring across diverse geographic regions and environmental settings. Major emission sources are often concentrated in areas with intensive fossil fuel production, extensive agricultural activities, and large urban centers with significant waste management operations. Emissions may vary seasonally and spatially due to differences in industrial activity, agricultural cycles, and waste decomposition rates. The global distribution of anthropogenic methane reflects complex interactions between human economic activities and natural environmental conditions, spanning continents, coastal zones, and inland regions.

== Monitoring and Measurement ==
Monitoring of anthropogenic methane emissions relies on a combination of atmospheric measurements, emission inventories, and modeling approaches. Key institutions involved include the United Nations Framework Convention on Climate Change (UNFCCC), which collects national and facility-level emission reports, and the National Oceanic and Atmospheric Administration ([https://en.wikipedia.org/wiki/National_Oceanic_and_Atmospheric_Administration NOAA]) Global Monitoring Laboratory, which provides atmospheric methane concentration trends. Additional data sources include the Emissions Database for Global Atmospheric Research (EDGAR) and scientific assessments such as the Intergovernmental Panel on Climate Change ([https://en.wikipedia.org/wiki/Intergovernmental_Panel_on_Climate_Change IPCC]) reports. Measurement methods encompass ground-based sampling, remote sensing from satellites and aircraft, and atmospheric inversion modeling to estimate emissions from observed methane concentrations.

Within the SIGNAL system, anthropogenic methane emissions are treated as a defined environmental signal whose boundaries and measurement conventions are described below.

== Signal Definition ==
This Damage Signal represents the total annual mass flux of methane emitted into the atmosphere from human-related sources, expressed in tonnes of CH₄ per year. It quantifies the net anthropogenic methane emissions as a DRIVER condition within the atmospheric domain, capturing emissions from fossil fuel extraction and use, agriculture, waste management, and other human activities contributing to methane release.

== Boundary Conditions ==
Boundary inclusions encompass all methane emissions directly attributable to human activities, including fossil fuel industry operations, enteric fermentation in livestock, rice paddy cultivation, landfills, wastewater treatment, and biomass burning linked to human land use. Boundary exclusions include natural methane sources such as wetlands, termites, wildfires unrelated to human activity, and geological seepage. Emissions from biogenic sources not influenced by human activity are excluded to isolate the anthropogenic component of methane release.

== Aggregation Semantics ==
Geographically, methane emissions are aggregated globally and can be disaggregated by country, region, or sector to support spatial analysis and reporting. Temporally, data are aggregated on an annual basis to align with international reporting cycles and to capture seasonal variability within a yearly framework. Cross-signal aggregation involves integrating methane emissions data with related environmental signals such as carbon dioxide emissions, nitrogen oxides emissions, and agricultural soil emissions to provide a comprehensive view of anthropogenic impacts on atmospheric composition and climate forcing. These aggregation practices facilitate multi-scale analysis and support policy-relevant assessments.

== Observational Status ==
Anthropogenic methane emissions are actively monitored through a combination of national reporting under the UNFCCC, atmospheric observations by NOAA and other agencies, and global emission inventories such as EDGAR. Data quality and coverage have improved over recent decades, enabling more accurate quantification and trend analysis. Future SIGNAL releases aim to incorporate enhanced spatial resolution, sector-specific emission breakdowns, and integration with complementary environmental signals to refine understanding of methane's role in climate forcing and support comprehensive environmental assessments.

== Related Signals ==
* Landfill methane emissions
* Annual nitrogen load delivered to freshwater receiving waters
* Freshwater phosphorus load delivered to receiving waters
* Habitat extent (area)
* Agriculture — Agricultural Soils Emissions
* CO2 emissions mass flux (generic)
* Nitrogen oxides emissions (anthropogenic)
* Industrial freshwater withdrawal (annual)

<!-- SIGNAL_EARTH_PEOPLE_START -->
== Key Associated People ==
* '''Marielle Saunois''' — Steward-candidate (Laboratoire des Sciences du Climat et de l'Environnement (LSCE)) [Domain expert]
* '''Rob Jackson''' — Advisor (Stanford University) [Domain expert]
<!-- SIGNAL_EARTH_PEOPLE_END -->

<!-- SIGNAL_EARTH_SOURCES_START -->
== Sources ==
* [https://gml.noaa.gov/ccgg/trends_ch4/ NOAA Global Monitoring Laboratory CH4 Trends (global monthly mean) — 2026 — NOAA GML]
* [https://www.ipcc.ch/report/ar6/wg1/ IPCC AR6 WG1 Chapter 5: Global Carbon and Biogeochemical Cycles — 2021 — IPCC]
* [https://doi.org/10.5194/essd-12-1561-2020 The Global Methane Budget 2000–2017 — 2020 — Earth System Science Data]
* [https://edgar.jrc.ec.europa.eu/ EDGAR methane emissions database]
<!-- SIGNAL_EARTH_SOURCES_END -->