Methane or CH4, is a colourless, odourless and highly flammable gas that is composed of hydrogen and carbon. It is also a powerful greenhouse gas, affecting climate change and contributing to global warming. Methane enters the atmosphere through both natural and human-related sources.
The primary natural sources for methane emissions include termites, wetlands and oceans. These natural sources produce 40% of all methane emissions. Human sources of methane emissions include livestock farming and landfills; however, the most important source of methane emissions created by human activity is the creation, production, transportation and use of fossil fuels. With this in mind, human activity is responsible for the majority of methane emissions. In fact, methane concentration levels have doubled over the last 150 years and this is largely due to human activities such as farming and fossil fuel usage [ref]. In fact, before the industrial revolution, the planet’s natural sinks kept methane levels in a safe range.
Today, humans are pushing out methane emissions at an alarming rate and at a much faster rate than earth can get rid of them.
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Methane and climate change
Climate change refers to the long-term shifts in weather patterns and temperatures. These kinds of shifts can be natural and based on variations in the solar cycle however, since the 1800s, human activities have been the primary driver of climate change and this is mostly due to the burning of fossil fuels such as coal, gas and oil.
Fossil fuels are a major source of greenhouse gas emissions, trapping the the sun’s heat, and raising the earth’s temperature. Carbon dioxide and methane are two of the most powerful greenhouse gases contributing to climate change, ultimately impacting our health, economy and environment.
Some of the ways in which climate change affects human health, the economy and the environment include:
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The warmer temperatures attributed to climate change increase the duration and frequency of heat waves. This poses significant health risks, especially for the elderly and young children
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Water quality and worsening air quality impact human health and this increases the spread of disease
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Rising sea levels due to climate change threatens ecosystems and coastal communities, resulting in displacement and migration
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Changes in rainfall patterns and the amount of stream flow effects water supplies, water quality and the production hydroelectricity
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Plant and animal lifecycle events such as reproduction and migration will change due to climate change thus affecting our ecosystems
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Extreme weather events increase and the intensity of these events, such as floods, waves and droughts, cause property damage, costly societal disruptions, and reduce affordability of insurance and living
These are just a few of the consequences that can occur due to climate change, and one of the major driving factors behind climate change is methane.
Since the industrial revolution, Methane accounts for 30% of the rise in global temperatures and this is why sustained and quick reductions in methane emissions are vital to reduce global warming and improve our air quality [ref].
There are two primary characteristics that determine the impact of greenhouse gases on our climate and these are:
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The amount of time they remain in our atmosphere
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The ability to absorb energy
With these two factors in mind, methane has a significantly shorter lifetime in the atmosphere when compared to the lifetime of carbon dioxide (that is 12 years in comparison to centuries) however, methane absorbs more energy than carbon dioxide while it exists in our atmosphere.
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Sources of methane emissions
Natural sources
Methane is released into the atmosphere through a variety of natural sources, as touched on above. From wetlands and termites to oceans, methane produced by natural sources is offset by what is known as natural methane sinks. This kind of emission has been happening for thousands of years, well before human interference and these emissions were not harmful to the planet – they were a part of its natural balance.
Below, we take a look at natural sources of methane emissions and the amount of methane contributed to the atmosphere, per year.
Wetlands
Wetlands are estimated to create 147 million tonnes of methane per year.
Wetlands are the largest source of natural methane gas emissions, producing 78% of all natural methane gas emissions.
Wetlands produce methane from what is known as microbial activity. Once methane is produced in wetlands, there are a variety of ways that the greenhouse gas is consumed and transported from the soil into the atmosphere, some of these ways include: plants, diffusion and bubbling.
Wetlands are the largest natural source of methane gas emissions and the water-logged conditions of these environments offer the ideal location for microbes. Part of the wetland methane gas emissions will be absorbed by microbes however, a large percentage escapes into the atmosphere – and this results in the release of 147 million tonnes of methane per year.
Termites
Termites are estimated to contribute 20 million tonnes of methane per year
On average, each termite produces about half a microgram of methane every day, this may sound like a small amount however, when multiplied by the world’s population of termites, global methane emissions from termites is estimated to be 20 million tonnes per year.
Termite methane is produced in the guts of a termite, through symbiotic bacteria and protozoa, which takes place during food digestion.
It is important to note that termite methane doesn’t always end up going straight into the atmosphere as many species are subterranean and live above or in the ground mounds. This means that most of the methane can be used by the soil before it makes its way to the atmosphere.
Oceans
Oceans are estimated to produce 19 million tonnes of methane per year.
The ocean is another source of natural methane gas. Microbes living in the ocean produce methane and create methane emissions. The methane created by oceanic microbes mixes with the water that surrounds it and after some time, it gets emitted into the atmosphere from the surface of the ocean.
Oceanic methane production makes up 10% of natural methane emissions and globally, the ocean produces 19 million tonnes of methane per year [ref].
Human sources
Since the industrial revolution of 1750, human activities have caused massive and increasing methane emissions. With the production of fossil fuel and livestock farming, methane emissions continue to rise and these sources are responsible for 60% of all human emissions [ref].
Below, we take a look at the human sources of methane emissions and the amount of methane contributed to the atmosphere, per year.
Fossil Fuel Production
Fossil fuel production is estimated to create 123 million tonnes of methane per year.
Fossil fuels, from production and distribution through to combustion, are the largest human source of methane gas emissions into the atmosphere.
These emissions are produced wherever fossil fuels occur and are released as soon as fossil fuels are extracted from the earth. This can come from natural gas (which is mostly methane), petroleum or coal.
Methane is released again through the handling of fossil fuels throughout the energy supply chain and this includes transportation, pipelines, trucks and delivery (and more). Methane can also leak through the refinement process of these fossil fuels and some methane can also leak when combustion equipment fails, such as flare stacks.
Natural gas is made up of mostly methane and any leakage from extraction to distribution and delivery will inevitably release methane straight into the atmosphere.
Coal is another main source of methane emissions into our atmosphere. In the formation of coal, pockets of methane become trapped around and inside the rock and with this in mind, coal mining activities including extraction and distribution, release this trapped methane. It is also important to note that methane gets emitted from active below ground and surface mines – as well as mines that have been abandoned.
Oil wells are also large methane deposits and methane will get released from these wells during the drilling and extraction process. Once again, the entire process from drilling to transportation and storage, is also a source of large methane emissions.
Another significant factor is incomplete combustion of fossil fuels. When fossil fuels are used to generate electricity, power vehicles or heat environments, methane is released.
For some perspective, fossil fuel, which is used across all our homes, is the largest source for methane emissions in the world.
With the above in mind, fossil fuel production, distribution and use creates 123 million tonnes of methane per year [ref].
Livestock Farming
Livestock farming is estimated to create 90 million tonnes of methane per year.
Enteric fermentation in farm animals is an important source of methane emissions into our atmosphere. Farm animals such as sheep, goats and cows are known as ruminant animals and during their digestion process, these animals produce large amounts of methane. Enteric fermentation happens due to the microorganisms in the stomach of these farm animals and this process creates methane. The methane is released by the animals through exhalation or flatus.
The reason this isn’t considered a natural source of methane gas emission is because humans are raising these animals for food and because of this, the emissions are related to human activity.
With this in mind, the meat humans eat every day has a significant impact on the environment and the acceleration of climate change. Livestock related methane emissions grow due to the increase in livestock population across the world. For some perspective, beef production has more than doubled since the 1960s.
With this in mind, livestock farming creates an enormous 90 million tonnes of methane every year.
Biomass Burning
Biomass burning is estimated to produce 38 million tonnes of methane per year.
Biomass burning refers to the burning of dead and living vegetation – including the human initiated burning of vegetation for land-use and land-clearing.
This kind of burning causes massive amounts of methane emissions and huge amounts can be produced when there is a large-scale burning.
Biomass burning is essentially open fires that are created by humans to destroy crops, crop waste and clear land for agricultural or other land uses. There are natural wildfires that can be known as biomass burning and these natural fires do create methane emissions however, the majority of biomass burning is caused by human activity.
Biomass burning is a massive problem for methane emissions and generates 38 million tonnes of methane every year.
Biofuels
Biofuels are estimated to produce 12 million tonnes of methane per year.
A biofuel refers to any biomass that is used to produce energy for domestic use or related purposes. In fact, 80% of biofuels get used for domestic purposes like cooking, lighting and heating. This is the largest contributor to biofuel emissions – with 2.7 billion people across the world using solid biofuels to heat and cook in their homes every day.
Biofuels are a significant source of methane emissions and incomplete biofuel combustion can lead to the production of methane. Each year biofuels produce 12 million tonnes of methane.
Rice Agriculture
Rice agriculture is estimated to produce 31 million tonnes of methane per year.
Rice agriculture is a large cause of methane, with paddy fields being large man-made wetlands. These lands have high moisture, depleted of oxygen and are made up of rich organic material.
All of this combined creates the perfect space for methane producing microbes. In the case of rice agriculture, some of the methane that is produced gets absorbed by microorganisms that consume methane but the majority of methane gets released into the atmosphere.
Rice agriculture creates 31 million tonnes of methane every year.
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The largest source of methane emissions
Human activities are the largest source of methane emissions into the earth’s atmosphere, with fossil fuels emitted 123 million tonnes of methane into the atmosphere per year. Since the industrial revolution, fossil fuel production as well as livestock farming, have caused the continued rise of methane which in turn, contributes to the climate crisis we are currently facing.
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Reduce your business’s carbon footprint with GHGSat
With leading-edge technology, organisations are leading the way in the mitigation, management and reduction of greenhouse gas emissions. The GHGSat team is proud to be a world-leader in high-resolution sensing of industrial greenhouse gas emissions from space and with advanced satellite technology, we are able to measure industrial emissions, transforming the world’s understanding of industrial pollution thus providing the opportunity for management and mitigation.
Methane emissions calculator
Committed to global industrial monitoring of greenhouse gas emissions to support emissions reduction strategies, GHGSat introduced a free Methane Emissions Calculator, making it easier to understand methane emission rates related to the natural gas industry and calibrate emissions measurements. Our Methane Emissions Calculator allows the calculation of the total cost of a methane leak and enables the conversion of emissions to different units – mass, volume, duration – of methane.
The calculator has many usages:
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To determine the value of natural gas product loss – emissions also affect the energy supply chain.
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To help set emission reduction targets and other greenhouse gas reduction initiatives.
These functions can lead to a more seamless communication of methane reduction rates.
Emissions Monitoring for Coal Mines
As fossil fuels are the greatest contributor to methane emissions across the globe, our high-resolution satellite-based emissions monitoring detects and measures methane emissions with accuracy. Monitoring frequently for gas emissions from coal mines is necessary in order to identify opportunities for better and cleaner operations [learn more].
Global emissions monitoring for oil and gas
With our global emissions monitoring for oil and gas technology, you are able to detect, monitor and measure methane emissions from oil and gas assets globally. With this technology, you will have the data to align your carbon intensity targets with operation optimizations and keep methane in the sales line, not vented to the atmosphere [learn more].
SPECTRA
Our emission intelligence empowers carbon-intensive industries and governments to achieve their emissions reduction goals.
GHGSat launched a free subscription to SPECTRA, our emissions intelligence platform. The platform includes an upgraded version of our methane map, as well as access to a gallery of samples of methane measurements from GHGSat and other satellites.
Explore methane like never before.
