UN satellite system to detect prolific methane emitters from space

Methane is a powerful greenhouse gas providing more than 80 times the warming power of carbon dioxide within the first 20 years of it reaching the atmosphere. It is currently estimated to contribute at least a quarter of today’s climate warming.

According to the Intergovernmental Panel on Climate Change, we must cut methane emissions at least 30 per cent by 2030 – the goal of the Global Methane Pledge – to keep the 1.5°C temperature limit within reach.

The Methane Alert and Response System (MARS) from the UN Environment Programme (UNEP) will allow it to corroborate emissions reported by companies and characterise changes over time. It will be part of the body’s International Methane Emissions Observatory (IMEO) strategy.

“As UNEP’s Emissions Gap Report showed before this climate summit, the world is far off track on efforts to limit global warming to 1.5°C,” said Inger Andersen, executive director of UNEP.

“Reducing methane emissions can make a big and rapid difference, as this gas leaves the atmosphere far quicker than carbon dioxide. The Methane Alert and Response System is a big step in helping governments and companies deliver on this important short-term climate goal.”

Other measures being taken as part of the IMEO include monitoring agricultural methane emissions using a combination of ground measurements and emerging satellite capacity.

MARS will be the first publicly available global system capable of detecting major methane emissions from space. It will use state-of-the-art satellite data to identify very large methane plumes and methane hot spots and support and track progress in lowering methane emissions.

UNEP will then notify governments and companies about the emissions, either directly or through partners, so that the responsible entity can take appropriate action.

Beginning with very large point sources from the energy sector, MARS will integrate data from the rapidly expanding system of methane-detecting satellites to include lower-emitting area sources and more frequent detection. Data on coal, waste, livestock and rice will be added gradually to the system.

“Cutting methane is the fastest opportunity to reduce warming and keep 1.5°C within reach, and this new alert and response system is going to be a critical tool for helping all of us deliver on the Global Methane Pledge,” said John Kerry, US special presidential envoy for climate.

“We are seeing methane emissions increase at an accelerated rate. With this initiative, armed with greater data and transparency, companies and governments can make greater strides to reduce methane emissions and civil society can keep them accountable to their promises,” said Dr Kelly Levin, science chief at the Bezos Earth Fund.