Satellites now flag very large methane releases and route the alert straight to operators. Here’s what a MARS notification actually is — and how to respond before it becomes a bigger problem.
What MARS is
The Methane Alert and Response System (MARS) is a public satellite detection-and-notification system run by UNEP’s International Methane Emissions Observatory (IMEO), launched at COP27. Using data from more than 30 satellite instruments (including ESA’s Sentinel-5P/TROPOMI and higher-resolution satellites for attribution), it detects very large methane emissions — on the order of 1,000 kg of methane per hour or more — attributes them to a facility and operator, and notifies the relevant government focal point.
Why it matters even though it’s “voluntary”
MARS itself isn’t an enforcement program — but a documented, satellite-confirmed large release doesn’t stay private. It draws regulatory attention, reputational scrutiny, and questions you’ll want to answer with data, not guesses. Treating a MARS alert as a real event is the cheap path.
How to respond
- Verify — is the plume real, is it current, and is it actually yours? Satellite attribution is approximate.
- Find the source — this is where ground-truth matters. An OGI survey and Method 21 monitoring locate and quantify the actual leaking component the satellite could only estimate.
- Fix and document — repair, re-monitor, and keep a defensible record of the whole response.
Where AIM fits
When the alert says “large release near your facility,” you need boots and instruments on the unit fast. We run rapid ground-truth OGI and Method 21 surveys to pin down the source, quantify it, track the repair, and build the record — so your response to a satellite alert is documented and defensible.
Frequently asked
What is a MARS methane alert?
MARS (the Methane Alert and Response System) is a UNEP/IMEO satellite system that detects very large methane emissions — around 1,000 kg per hour or more — attributes them to a facility and operator, and notifies governments and, for OGMP 2.0 member companies, the operators directly.
Is a MARS alert a violation or fine?
No. MARS is a detection-and-notification system, not an enforcement action, and responding is voluntary. But a satellite-confirmed large release attracts regulatory and public scrutiny, so the practical move is to verify and resolve it as if it matters — because it does.
How do we find the source of a satellite-detected leak?
Satellite attribution is approximate — it points to a facility, not a component. Locating the actual leak takes ground-truth: an OGI survey to see the plume and Method 21 monitoring to quantify it, followed by repair and re-monitoring with documentation.
This is general information, not a regulatory applicability determination or legal advice. Rules, deadlines, and how they apply change and depend on your specific equipment, permit, and facility. Confirm your obligations with a qualified professional or your permitting authority.
Two tools that keep operators ahead of the next methane alert
The same regulatory engine we run for clients, put in your hands.
EHS Compliance Hub
Track every LDAR rule, Federal Register update, and compliance deadline that hits your facility — in one place, updated live. Free to use.
QuickScope™
Database-driven field inspections powered by the same rules engine as the Hub — built to make LDAR surveys faster and audit-ready.