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STORY: Methane.

It's rapidly rising levels in the atmosphere could threaten efforts to curb global warming by mid-century.

:: Clean Air Task Force

Scientists and policymakers are urging aggressive action to stunt the output of the potent greenhouse gas.

But why is controlling methane emissions so important?

:: Heat-trapping power

:: NASA Scientific Visualization Studio

Atmospheric methane levels in the last five years have risen at their fastest rate since record-keeping began.

:: Clean Air Task Force

Methane molecules are more powerful in trapping heat than carbon dioxide, or CO2, meaning it takes fewer of them to cause the same amount of warming.

:: NASA Scientific Visualization Studio

Scientists say they have contributed around 0.5 degrees Celsius of warming so far, or roughly one third of warming experienced since pre-industrial times.

Reducing methane levels could not only have a more immediate effect than reducing CO2, but according to the United Nations is likely cheaper.

:: Surging emissions

Methane concentrations are also rising faster than any other major greenhouse gas.

According to the 2024 Global Methane Budget, two thirds are driven largely by human activities such as agriculture, fossil fuel activities, landfill and waste.

:: N2 Applied

The report, published every five years, found methane emissions from these human activities have risen overall by 20% over the last two decades.

Nearly 160 countries have pledged to cut 30% of their output levels by the end of this decade.

Most of the methane mitigation efforts underway are focused on oil and gas, where emissions are easier to tackle according to the food-focused investor initiative called FAIRR.

:: Natural sources are a concern

The remaining third of the world's methane emissions comes from natural sources such as thawing permafrost, peat bogs and wetlands.

Animals, including humans, are also a source of methane.

While it is easy to measure atmospheric methane, understanding where it comes from is crucial for tackling the problem.

:: NASA's Goddard Space Flight Center

Scientists are analyzing distinct isotope signatures in methane, to investigate whether the detected gas comes from biological sources or industry.