Is methane more harmful than CO2?

In order to stop climate change, not only the carbon dioxide emissions have to be reduced. Methane is also accumulating too much in the atmosphere and is driving global warming. What causes the emissions and how can they be contained?

The most important questions and answers

What is methane?

Methane is one of the six substances listed as greenhouse gases in the Kyoto Protocol. Methane is an odorless gas that has the chemical formula CH₄. According to the Federal Environment Agency Methane is one of the most important greenhouse gases. In recent years, it was responsible for around 6.5 percent of greenhouse gas emissions in Germany. However, the share of global methane emissions in climate change is estimated at around 20 to 30 percent, because methane binds more heat than CO₂ in the short term (see below).

How is methane formed?

Methane is always formed when organic material is broken down in the absence of oxygen. In nature, methane is released naturally in swampy areas. It is also one of the main components of natural gas. When using natural gas to generate energy, the methane burns and CO₂ is produced. But the methane itself also ends up in the atmosphere. Another important cause of man-made methane emissions are agriculture and the keeping of livestock, especially cattle. Plants are broken down by bacteria in the stomachs of ruminant animals. This produces methane, which is emitted during digestion. However, methane is also released during natural gas production and hard coal mining, as well as in landfills and in waste water and sewage sludge treatment. Small amounts of methane emissions are caused by traffic and industry.

Excess methane from natural gas production accounts for a large proportion of emissions. According to one current report According to the British newspaper “Guardian”, natural gas production in Turkmenistan releases more methane per year than the whole of Great Britain produces. But according to one, there are also other countries such as the USA or Russia study Larger leaks from which large amounts of methane are constantly escaping during oil or gas production.

How harmful is methane for the climate?

Just like the more well-known greenhouse gas carbon dioxide (CO₂), methane in the atmosphere also absorbs heat radiation from the sun (infrared radiation). As a result, heat reflected from the earth can no longer completely escape from the atmosphere. Instead, it accumulates and contributes to global warming. In the short term, methane gas has a much stronger impact than CO₂. Over a 100-year period, methane is about 28 times more likely to cause global warming than the same amount of carbon dioxide, according to calculations by the Intergovernmental Panel on Climate Change (IPCC). If you only look at a period of 20 years, the effect is even more than 80 times greater. However, methane in the atmosphere is broken down faster than CO₂. According to the Federal Environment Agency, methane only lasts about twelve years in the atmosphere on average, while CO₂ has not yet completely decomposed even after 1000 years.

How can methane emissions be reduced?

Methane has accumulated in the atmosphere in recent years, although measures have already been taken to reduce man-made emissions. It is possible that climate change is now leading to more methane being released from natural sources such as swamps or thawing permafrost. It is also unclear whether leaks in natural gas production are sufficiently recorded.

Researchers from Queen Mary University in London recently had criticized in a publicationthat methane is not sufficiently taken into account in measures to combat climate change. A reduction in emissions offers an “enormous opportunity to limit warming in the short term,” according to a statement from the university.

One way to effectively reduce methane emissions would be to improve the prevention and earlier repair of leaks in natural gas production. Another option is to reduce methane emissions from agriculture. American researchers had In a study found that methane contributes about 60 percent of global greenhouse gas emissions from the food supply. In addition to beef production, rice cultivation and the production of dairy products are primarily responsible for methane emissions. The researchers believe, however, that emissions could be reduced by changing production conditions and consumer behavior and by reducing food waste. A more climate-friendly production of meat, dairy products and rice alone could help save about a quarter of the forecast temperature increase of 0.9 degrees.

Various models are already being tested to reduce methane emissions from cattle farming. It could be like that Feeding the seaweed Asparagopsis reduce emissions drastically. Other feed additives that could reduce methane emissions are also being tested.