Architecture
Global Energy Monitor’s Global Methane Emitters Tracker uses a two-level system for organizing information, consisting of both a database and asset-level profiles hosted on GEM.wiki.
The database tracks individual coal mines, oil and gas extraction sites, natural gas transmission pipelines, and remotely-sensed methane observations. GEM.wiki pages are created for each methane observation. The database is updated bi-annually in November and May.
Research Process
Global Methane Emitters Tracker uses asset level infrastructure data in Global Energy Monitor’s Global Coal Mine Tracker, Global Oil and Gas Extraction Tracker, and Global Gas Infrastructure Tracker.
The infrastructure data on coal mine, oil and gas units, and pipelines are collected from and validated through five main sources:
- Government data on individual units, country energy and resource plans, and government websites tracking extraction permits and applications.
- Reports by state-owned and private companies;
- News and media reports;
- Local non-governmental organizations tracking extraction permits and operations;
- On-the-ground contacts who can provide first-hand information about a project.
For plume emissions data, GEM has used emissions estimates provided by CarbonMapper, who created the imagery. For coal mine emissions estimates, GEM calculates coal mine methane emissions based on production, gas content at given mine depth, and an emissions factor coefficient. For pipelines, GEM utilizes a Tier 1 IPCC methodology. For oil and gas reserves, GEM has developed an in-house adaptation of the Oil Climate Index + Gas methodology developed by the Rocky Mountain Institute.
GEM has used coal mine emissions estimates developed in-house, emissions estimates of oil and gas published by Climate Trace and Oil Climate Index + Gas (OCI+), and CarbonMapper’s published satellite emissions data.
Further details on our methodology can be found at Global Methane Emitters Tracker methodology on GEM.wiki.
Wiki Pages
For each attributed satellite methane observation, a wiki page is created on Global Energy Monitor’s GEM.wiki. Wiki pages provide a repository for in-depth information. Under standard wiki convention, all information is linked to a published reference.
Mapping
To allow easy public access to the results, Global Energy Monitor worked with GreenInfo Network to develop a map-based and table-based interface using the Leaflet Open-Source JavaScript library. In the case of exact coordinates, locations have been visually determined using Google Maps, Google Earth, and Planet Labs. For proposed projects, exact locations, if available, are from permit applications or other company documentation. If the location of a unit or proposal is not known, GEM identifies the most approximate location.