Methane, a challenge for global climate stability

Methane, known chemically as CH₄, is a gas that is harmful to the atmosphere and to living beings because it has a high heat-trapping capacity. For this reason, it is the second largest contributor to the greenhouse effect after carbon dioxide (CO2).

It is a simple hydrocarbon that can come from natural sources, such as volcanic activity, as well as from human activities such as intensive agriculture, livestock farming and the exploitation of fossil fuels, generating what is known as anthropogenic methane.

The concentration of methane in the atmosphere has increased significantly since the Industrial Revolution due to the progress that machines have brought to human activities. This increase is worrying, as methane has a global warming potential 25 times greater than carbon dioxide over a 100-year horizon.

The concentration of methane in the atmosphere has more than doubled in the last 200 years. Scientists estimate that this increase is responsible for 20-30% of global warming since the Industrial Revolution (which began in 1750). Climate NASA.

Monitoring methane is essential to understand and prevent its impact on the environment and its negative effects on life on the planet.

How methane is formed

Methane is a colourless, odourless gas that belongs to the category of hydrocarbons. Its chemical formula is CH4, which indicates that it is composed of one carbon atom and four hydrogen atoms.

The formation of methane in nature occurs through the anaerobic decomposition of organic matter. This process takes place in waste from human production, in wetlands such as marshes and lakes and in the marine sediments of the oceans, and in the intestines of ruminant animals as well as in their waste. This process generates what is known as natural methane.

This is methanogenesis, a biological process carried out by microorganisms known as methanogenic archaea. These microorganisms break down organic matter under anaerobic conditions, i.e. in the absence of oxygen, producing methane as a by-product.

Geological processes also contribute to the formation of methane in the subsoil, constituting natural gas through the thermal decomposition of organic matter in the subsoil.

In turn, methane originates anthropogenically through activities such as agriculture, animal husbandry, solid waste and sewage, as well as the exploitation and use of fossil fuels.

Understanding how methane is formed and the sources of its emissions is crucial for developing effective strategies to mitigate its impact on climate change and, at the same time, harness its potential as an energy source.

The science of methane, a potent greenhouse gas - Kunak

The science of methane, a potent greenhouse gas

Main sources of methane emissions to the atmosphere

A significant part of atmospheric methane comes from human activities, the so-called anthropogenic methane. The main sources from which it derives are:

Agriculture

According to the World Bank, it accounts for approximately 41% of methane emissions from human activity, in particular rice cultivation and burning of agricultural waste.

Solid waste landfills

The storage and management of waste generated by human activity is the third largest global source of methane emissions.

Wastewater

Methane production occurs during the handling and treatment of municipal wastewater. It is due to the anaerobic decomposition of organic waste.

According to the Global Methane Initiative, most developed countries rely on centralised aerobic treatment systems to collect and treat municipal wastewater. These systems produce small amounts of methane, but also large amounts of biosolids that could lead to high rates of methane emissions.

In developing countries where there is little or no wastewater collection and treatment, systems tend to be anaerobic, thus leading to higher methane emissions.

Livestock

Domestic ruminant animals, such as cows and sheep, generate methane through their digestive process, known as enteric fermentation. This process releases methane directly in the gut of ruminants and in the handling of manure.

Methane accounts for about 19% of global greenhouse gas emissions. Rice production accounts for 8%, livestock 32% and waste 18% of all human-caused methane emissions.

Natural gas

Methane can also be formed through geological processes, such as the thermal decomposition of organic matter underground, which leads to the formation of natural gas. It is accumulated in natural underground reservoirs from which it is extracted, through drilling, as a crucial energy source for many global economies.

Being a highly flammable gas makes it an efficient and relatively clean source of energy when burned, compared to other fossil fuels. The extraction and use of methane gas, however, is not without environmental challenges due to the risk posed by its release into the atmosphere.

Methane leaks during the extraction, processing, transport and storage of natural gas (as with oil) represent a major source of methane emissions to the atmosphere. The energy industry is therefore investing in technologies and new methods to reduce these emissions and mitigate their environmental impact.

Industrial activity

Industry also contributes to methane emissions, particularly through industrial processes that use or produce methane as a by-product. For example, the production of methanol and ammonia, among other chemical compounds, can release methane into the environment.

Organic matter

In nature, methane is produced through the anaerobic decomposition of organic matter in wetlands such as marshes and lakes and in the oceans. This process contributes 30% to the increase in natural methane and thus to the increase in global methane emissions.

However, it is human activity that has significantly increased total methane emissions, especially through the exploitation and use of fossil fuels (oil and natural gas), waste management and intensive agriculture. Urbanisation and the growth of cities have also multiplied the sources of anthropogenic methane, due to increased generation of solid waste and wastewater and increased global energy demand.


In summary, both natural and anthropogenic sources of methane have a considerable impact on the atmosphere and on climate change, underlining the need to establish effective strategies to measure and mitigate such life-damaging emissions.

The importance of measuring methane in the air

Natural methane, while also contributing to global warming, has not shown the same dramatic increase as anthropogenic methane in recent decades.

In fact, a recent NASA study using satellite data has concluded that, at least in the US, the proportion of this climate super pollutant with a 30 times greater potential to contribute to climate change than carbon dioxide has been underestimated. This greenhouse gas is currently responsible for about one-third of the global warming produced by all greenhouse gases (GHGs).

Measuring the concentration of methane in the air is crucial for several reasons:

Contribution to the greenhouse effect

It is a very potent greenhouse gas with a significant impact on climate change. Although methane is less abundant in the atmosphere than carbon dioxide, it is more heat-trapping than carbon dioxide.

Public health

Exposure to high concentrations of methane can cause respiratory problems and aggravate pre-existing lung diseases. Reducing methane in the air generally reduces the incidence of air pollution-related diseases.

Air quality

Methane can react in the atmosphere to form tropospheric ozone, a pollutant that affects air quality, making it harmful to human health and the environment.

Emission sources

Measuring methane in the air helps to define the sources of emissions, whether natural or anthropogenic, in order to implement measures to effectively reduce them.

In conclusion, measuring methane in the air is essential to understand and monitor its impact on the global climate, as well as on human and ecosystem health. Controlling its presence in the atmosphere is also essential to maintain healthy air quality and to develop strategies to minimise the adverse effects of its presence in the atmosphere.

Impact of methane on the environment

In addition to its contribution to global warming, methane also affects air quality and thus public health.

Although methane is a natural component of the carbon cycle, its increase due to human activities represents a significant challenge to global climate stability. It is a valuable component of natural gas and has important industrial applications, but its negative environmental impact underlines the need for careful management and effective policies to reduce its emissions.

Why it is important to reduce methane in the air

The impact of atmospheric methane on the greenhouse effect is of particular concern because of its increasing concentration in the atmosphere and the resulting increase in global temperature. Rising global temperatures can lead to major environmental catastrophes such as the disappearance of glaciers, rising sea levels and extreme weather events such as floods and droughts.

Methane is also a dangerous chemical compound because it is a highly flammable gas that can cause explosions in high concentrations.

Reducing methane emissions is therefore crucial to mitigating climate change and protecting both the environment and public health.

If we manage to reduce methane levels in the atmosphere drastically, it will have an immediate effect on global warming within a few years, as methane gas has a very short lifetime (maximum 12 years), unlike CO2 which persists in the air for more than 100 years.

Strategies to reduce methane emissions and thereby significantly improve air quality include:

  • Improving natural gas capture, transport, utilisation and storage technologies.
  • Optimising agricultural and livestock practices with more sustainable techniques.
  • Promoting the use of renewable and clean energy instead of fossil fuels.
  • Optimise the management of organic waste and wastewater.
  • Implement the use of biogas or methane generated and reconverted into usable energy.
  • Encourage waste recycling and composting.

In order to implement all these effective actions to reduce the presence of methane in the atmosphere, given its importance for climate change, it is necessary to have accurate data on its presence and levels in the air. This is the only way to verify that the actions undertaken to reduce the presence of this harmful greenhouse gas are the most effective.

Methane policies and regulations

Methane policies and regulations have become crucially important in recent years due to growing concern about climate change and the need to reduce greenhouse gas emissions. The worldwide commitment to reduce its emissions globally is an important action in the face of climate change because its reduction in the atmosphere alone would have an effective impact on global warming.

Many countries and international organisations are implementing strict policies to control and reduce natural and anthropogenic methane emissions.

In the United States, for example, the Environmental Protection Agency (EPA) has established regulations requiring oil and gas industries to detect and repair methane gas leaks. These regulations also include the implementation of advanced technologies to capture methane that would otherwise be released into the atmosphere.

Similarly, the European Union has adopted a comprehensive strategy to reduce methane emissions, including measures to improve the efficiency of natural gas operations and promote sustainable agricultural practices.

In addition to national regulations, there are international agreements that seek to address the atmospheric methane problem globally. Such as the Paris Agreement, an international climate change treaty that is legally binding. It was adopted at COP21 in Paris in 2016. Although it focuses primarily on carbon dioxide, it also recognises the importance of reducing other greenhouse gases, including methane, in order to limit global warming preferably to 1.5°C and thus combat climate change and adapt to its effects.

In this context, especially to reduce potent but short-lived climate pollutants such as methane, initiatives such as the Global Methane Assessment of the Climate and Clean Air Coalition (CCAC) have emerged. According to its objectives:

“Actions that address climate change and air pollution at the same time achieve greater results. We promote actions to reduce short-lived climate pollutants that have rapid impacts on global warming, air quality, food security and human health.”

This coalition works with governments, businesses and non-governmental organisations to develop and promote best practices and technologies to minimise methane emissions, among other pollutants, in key sectors such as energy, agriculture and waste.

The Global Methane Pledge, proposed in 2021 by the European Union and the United States, gained the support of 103 countries that pledged to reduce global methane emissions by 30% by the end of the decade. Reaching this target means a 0.2°C reduction in global warming over the next 30 years (until 2050).

Rapidly reducing methane emissions is widely regarded by the countries that have signed up to the agreement as the most effective strategy for reducing global warming. They are also committed to moving towards the use of the best available monitoring methodologies to quantify methane emissions, with a particular focus on high-emission sources.

To achieve this, it is essential to have reliable data on the presence of methane in the air, as well as the level at which it is present. This is the way to prioritise the most effective abatement measures and to achieve adaptation of anthropogenic activities.

In addition, according to the Global Methane Assessment of the Climate and Clean Air Coalition (CCAC) and the United Nations Environment Programme (UNEP), achieving the 2030 target for reducing methane emissions would prevent more than 200,000 premature deaths, hundreds of thousands of asthma-related emergency room visits and more than 20 million tonnes of crop losses per year by 2030.

In short, methane policies and regulations are essential to mitigate its environmental impact and move towards a more sustainable future, requiring a coordinated effort at local, national and international levels to ensure the continued existence of life on the planet.