Satellites pinpoint vast methane leaks from landfills driving global heating

There have been more than 1,000 huge leaks of the greenhouse gas methane from landfill waste dumps around the world since 2019, the Guardian can reveal.

- Damian Carrington & Seán Clarke

Analysis of global satellite data shows the populous nations of south Asia are a hotspot for these superemitter events, as well as Argentina and Spain - developed countries where proper waste management should prevent leaks.

Landfills emit methane when organic matter such as food scraps, wood, card, paper and garden waste decompose in the absence of oxygen.

Methane traps 86 times more heat in the atmosphere than carbon dioxide over 20 years, making it a critical target for climate action.

Scientists have said emissions from unmanaged landfills could double by 2050 as urban populations grow, blowing the chance of avoiding climate catastrophe.

A total of 1,256 methane superemitter events occurred between January 2019 and June 2023, according to the data. Pakistan, India and Bangladesh lead the list of nations with the most large leaks, followed by Argentina, Uzbekistan and Spain.

Landfill emissions can be reduced by creating less organic waste in the first place, diverting it away from landfill, or at least capturing some of the methane that is being released from the landfills.

Action to stem methane leaks slows global heating faster than almost any other measure, with some measures even paying for themselves when the captured gas is sold as fuel.

Methane emissions have accelerated since 2007 and cause a third of the global heating driving the climate crisis today. The acceleration has alarmed scientists, who fear it is the biggest threat to keeping below 1.5C of global heating and could trigger catastrophic climate tipping points.

Decomposing waste is responsible for about 20% of human-caused methane emissions. Fossil fuel operations cause 40% of emissions, many of which could be easily fixed. Cattle and paddy fields cause the other 40%.