Study: Climate impact of butter 3.5 times greater than plant-based spreads

The climate impact of butter is higher in large part due cow's methane-heavy farts
The climate impact of butter is higher in large part due cow’s methane-heavy farts

Cow’s methane-heavy burps and farts blamed for CO2 associated with butter in study commissioned by margarine maker Upfield

The climate impact of consumer diets has yet again fallen under the spotlight, after research this week concluded butter is 3.5 times more harmful to the environment on average than margarine and plant-based spreads, due in large part to cows’ methane emissions.

The study was commissioned by global margarine maker Upfield – responsible for plant-based brands including Flora, Rama and Blue Band – in another sign of how firms are seeking to promote the climate credentials of their products to increasingly eco-conscious consumers.

It asked scientists to carry out a large-scale life cycle assessment looking at the production, transport, sale, and use of 212 plant-based spreads and margarines sold across 21 European and North American markets, and then compare their greenhouse gas emissions to the impact of 21 dairy butters.

The results found the average CO2 impact for every kilogram of plant-based spread and margarine produced was around 3.3kg, compared to 12.1kg of CO2 equivalent for dairy-based products, making emissions from butter around 3.5 times higher.

The bulk of emissions associated with butter occur during milk production, according to the study, which found enteric emissions from cows – aka methane from burping and farting – made up 39 per cent of greenhouse gases from dairy-based spreads.

It means that just one 250g of butter results in the equivalent of 1kg of cow emissions, the study estimated, with methane a particularly potent greenhouse gas which is around 80 times more powerful than CO2 at trapping heat, and responsible for around a quarter of global warming.

Every one of the 212 plant-based spreads analysed fared much better in the study in terms of carbon impact, with associated emissions ranging from less than 1kg to almost 7kg, whereas butter products generated between over 8kg to nearly 17kg of CO2 for every kilogram produced.

Beyond emissions too, the life cycle assessment – the largest of its type to date, according to Upfield – concluded that margarines and plant-based spreads consistently had lower impacts than butter in terms of climate, water and land.

Cattle feed production including cow burps, farts, and manure management “contributed significantly to climate change impacts, with a higher impact than most other factors”, the study found. Some farming groups have argued that new diet supplements and other technologies can serve to curb methane emissions from cattle, but the industry is still regarded as a large and growing source of emissions.

Sally Smith, head of sustainability at Upfield, said the study highlighted the need for a “fundamental transformation of our food system” in order to tackle climate change, arguing that people in western countries needed to cut down on their meat and dairy intake.

She also argued it was important for firms to help consumers to understand the impact of their food choices on the planet. “It is our responsibility as a forward-thinking company to understand and act to address the impact of our plant-based products on the environment,” said Smith. “A shift to regenerative agricultural practices will be key for both arable and dairy farmers. Robust lifecycle assessments help ensure that our approach is data driven and grounded on the latest scientific evidence.”

NASA Flights Detect Millions of Arctic Methane Hotspots

Thermokarst lake in Alaska
The image shows a thermokarst lake in Alaska. Thermokarst lakes form in the Arctic when permafrost thaws. Credit: NASA/JPL-Caltech
› Larger view

Knowing where emissions are happening and what’s causing them brings us a step closer to being able to forecast the region’s impact on global climate.

The Arctic is one of the fastest warming places on the planet. As temperatures rise, the perpetually frozen layer of soil, called permafrost, begins to thaw, releasing methane and other greenhouse gases into the atmosphere. These methane emissions can accelerate future warming – but to understand to what extent, we need to know how much methane may be emitted, when and what environmental factors may influence its release.

That’s a tricky feat. The Arctic spans thousands of miles, many of them inaccessible to humans. This inaccessibility has limited most ground-based observations to places with existing infrastructure – a mere fraction of the vast and varied Arctic terrain. Moreover, satellite observations are not detailed enough for scientists to identify key patterns and smaller-scale environmental influences on methane concentrations.

In a new study, scientists with NASA’s Arctic Boreal Vulnerability Experiment (ABoVE), found a way to bridge that gap. In 2017, they used planes equipped with the Airborne Visible Infrared Imaging Spectrometer – Next Generation (AVIRIS – NG), a highly specialized instrument, to fly over some 20,000 square miles (30,000 square kilometers) of the Arctic landscape in the hope of detecting methane hotspots. The instrument did not disappoint.

“We consider hotspots to be areas showing an excess of 3,000 parts per million of methane between the airborne sensor and the ground,” said lead author Clayton Elder of NASA’s Jet Propulsion Laboratory in Pasadena, California. “And we detected 2 million of these hotspots over the land that we covered.”

The paper, titled “Airborne Mapping Reveals Emergent Power Law of Arctic Methane Emissions,” was published Feb. 10 in Geophysical Research Letters.

Within the dataset, the team also discovered a pattern: On average, the methane hotspots were mostly concentrated within about 44 yards (40 meters) of standing bodies of water, like lakes and streams. After the 44-yard mark, the presence of hotspots gradually became sparser, and at about 330 yards (300 meters) from the water source, they dropped off almost completely.

The scientists working on this study don’t have a complete answer as to why 44 yards is the “magic number” for the whole survey region yet, but additional studies they’ve conducted on the ground provide some insight.

“After two years of ground field studies that began in 2018 at an Alaskan lake site with a methane hotspot, we found abrupt thawing of the permafrost right underneath the hotspot,” said Elder. “It’s that additional contribution of permafrost carbon – carbon that’s been frozen for thousands of years – that’s essentially contributing food for the microbes to chew up and turn into methane as the permafrost continues to thaw.”

Scientists are just scratching the surface of what is possible with the new data, but their first observations are valuable. Being able to identify the likely causes of the distribution of methane hotspots, for example, will help them to more accurately calculate this greenhouse gas’s emissions across areas where we don’t have observations. This new knowledge will improve how Arctic land models represent methane dynamics and therefore our ability to forecast the region’s impact on global climate and global climate change impacts on the Arctic.

Elder says the study is also a technological breakthrough.

“AVIRIS-NG has been used in previous methane surveys, but those surveys focused on human-caused emissions in populated areas and areas with major infrastructure known to produce emissions,” he said. “Our study marks the first time the instrument has been used to find hotspots where the locations of possible permafrost-related emissions are far less understood.”

More information on ABoVE can be found here:

Are we measuring ruminant methane emissions correctly?

17 January 2020

Researchers at Oxford University have developed GWP*, a new climate metric that accurately measures the impact of methane emissions on global warming – recontextualising the debate surrounding ruminant methane emissions and climate change.

ffinlo Costain, host of FAI Farm’s Farm Gate podcast interviewed Myles Allen and John Lynch from Oxford University to explore their new method of measuring the impacts of methane on climate change. GWP* is a new metric for global warming potential that measures the change in emission rates for methane instead of measuring emissions by volume. According to their research, GWP* gives a more accurate picture of the influence greenhouse gases have on the world’s climate than existing measures, which assign gases a nominal CO2 equivalent number.

Current climate measures, like GWP100, categorise ruminant-emitted methane and agricultural activities among the greatest contributors to climate change. GWP100 reaches this conclusion by comparing the total amount of emissions and extrapolating the potential impacts on the global climate. According to Roland Bonney, co-founder of FAI Farms and Benchmark Holdings plc, many farmers and farm organisations feel unfairly demonised by these conclusions and public reaction to them. Allen and Lynch echo this view and assert that the GWP100 metric doesn’t capture the full relationship between emissions and climate change.

Bonney asserts that raising ruminants sustainably can be part of the solution to climate change. Raising cattle and sheep in a mixed rotation system, ensuring they are grass-fed and that they have access to natural pastureland can reduce greenhouse gas emissions significantly. In his view, how we farm has a greater impact on global climate than what we choose to eat.

The differences between methane and carbon dioxide

Though both methane and CO2 contribute to climate change, they impact global temperatures differently. Humans emit more carbon dioxide than any other greenhouse gas and it remains the largest contributor to climate change. Though some CO2 can be absorbed by the ocean or be fixed in plant biomass, the bulk of human emissions go into the atmosphere. According to Allen, the CO2 left in the atmosphere causes a persistent warming effect over thousands of years, making its impact more cumulative than other gasses. Unless humans ramp up efforts to remove carbon, it will remain in the environment.

In contrast, methane is emitted in smaller quantities. The gas has a stronger warming effect than CO2, but it breaks down quickly. This means that after a few decades, the methane will be out of the atmosphere and any warming affects will cease.

When describing the different impacts of the gases, Lynch compared the impacts of methane emissions to drinking excessively and getting a hangover – the immediate effects will set you back, but as long as you don’t drink to excess again, the pain and nausea will dissipate. Carbon dioxide, on the other hand, is more akin to lead poisoning – exposure will cause immediate negative effects, and sustained exposure will cause significant damage in the future.

Metaphors aside, comparing one tonne of emitted CO2 to one tonne of emitted methane (CH4) doesn’t give researchers an accurate picture of the gases’ warming potential. Allen’s research indicates that for methane to have the same warming effect as CO2, humans would need to increase methane emissions by multiple tonnes per year and maintain that emissions level indefinitely. In his view, it’s more appropriate to compare the emission rates of methane with a single tonne of emitted carbon dioxide – the central aim of the new GWP* measure. The new metric will also give more accurate climate forecasting than the current GWP100 standard.

GWP* appears to capture these subtleties more effectively than GWP100. Researchers at the SRUC found that measuring the warming impact of farms with a traditional carbon calculator overestimated the impact of farm emissions on climate. When they used GWP* to analyse the same farm data however, methane emissions fell by 75 percent, halving the total climate impact of agricultural emissions.

Ruminant methane and GWP*

In Allen’s analysis, methane’s contribution to climate change is historic – we are feeling the effects of methane pulses from 50 years ago when the global ruminant herd increased. Ruminants contribute to global methane emissions as the herd expands. A new source of methane will have a huge effect, but a sustained source won’t be as impactful. If the herd remains stable or declines (which is happening currently), the methane they produce won’t add to the warming that’s already occurred. Allen argues that the methane produced by the world’s ruminants is keeping global temperatures at stasis – it isn’t contributing to warming or cooling either way.

GWP* allows researchers to differentiate between new sources of methane and existing ones, meaning that fluctuations in the global ruminant herd can be accurately accounted for. According to Lynch, analysing discrete methane sources makes GWP* more accurate and prevents overestimates of the gas’s climate effects.

In Allen’s view, removing all ruminants in order to tackle methane emissions wouldn’t provide a huge climate benefit. Culling ruminants would only give the climate a temporary pulse of cooling – a temporary reduction of 0.1 degrees at the absolute maximum. That’s the equivalent of a few years’ worth of warming from CO2 emissions. Instead of focusing solely on ruminant emissions, activists should also account for methane leakages in Britain’s natural gas infrastructure. Both Lynch and Allen agreed that eliminating CO2 emissions would do more to counteract climate change than simply reducing methane produced by ruminants.

Refocusing on carbon

Allen told Costain that though reducing methane would help the climate, tackling carbon emissions from the fossil fuel industry is more pressing. The emissions from this sector are “additional” to the world’s existing carbon cycle and cause present and future warming events. Unless the UK and other countries enact zero net carbon emissions policies, global climate change will continue. Lynch echoed these sentiments, saying that carbon emissions needed to be removed or offset to stabilise global temperatures.

Listen to the Farm Gate podcast with ffinlo Costain here.


by: Murat Suner

We are experiencing long shifts of climatic conditions that are characterised by a change in temperature, rainfall, winds, and other indicators.

Currently, the level of greenhouse gases in the atmosphere is much higher than in the past years, and its ability to trap heat is changing.

Burning fossil fuels and deforestation are the primary causes of climate change. It presents a substantial threat to humans and animals now and in the future. The following are some of the biggest human causes of climate change:


These gases accumulate in the atmosphere, blocking heat from escaping, and they don’t respond to the temperature changes (the greenhouse effect). When they remain for an extended period in the atmosphere, they are likely to cause climate change.

Greenhouse gas emission is a major human causes of climate change, and their sources include transportation, electricity production, burning fossil fuel in industries, commercial and residential application, agriculture, and land use. These gases include;


Carbon dioxide (CO2, or Carbon IV Oxide) is the main greenhouse gas produced through human activities that leads to adverse climate changes. It is a result of burning fossil fuels like coal, oil, and gas. Fossil fuel generates electricity worldwide, leading to high emissions of CO2. Locomotion is the second-largest source of carbon emission; humans contribute daily to CO2 emissions by use of transport vehicles either for leisure or business purposes.

Carbon stored in the form of fossil fuels is more stable, and when heated, they release the stored carbon in the form of CO2. If humans couldn’t burn these fuels for energy, the carbon is unlikely to reach the atmosphere.

We use fossil fuel to power cars, machines, and generate electricity, and as the human population increases, more fuel is used, leading to higher CO2 emissions.


Methane accounts for about 16 percent of greenhouse gas emissions. The petroleum industry and agriculture emit methane, especially from the digestive systems of grazing animals, manure management, and rice cultivation.

It also accumulates through waste decomposition in landfills. It is a far more active greenhouse gas than CO2.


Cultivation practices like the use of organic and commercial fertilisers lead to the emission of nitrous oxide. It also accumulates in the atmosphere through fossil fuel combustion, nitric acid production, and biomass burning.


Chlorofluorocarbons and hydrofluorocarbons are used in home appliances like the refrigerator and industrial applications. They are associated with severe atmosphere impacts like ozone layer depletion and heat-trapping.


They are primarily used in dielectric materials like the dielectric liquids and for special medical procedures. Also, they act as insulators in high voltage applications like the transformers and grid switching gear.


Deforestation is one of the major human causes of climate change; trees capture greenhouse gases such as CO2, preventing them from accumulating on the atmosphere, which could result in warming our planet. Most forests are getting cleared to create space for agriculture, buildings, and other human activities.

Trees take in carbon dioxide and release oxygen to the atmosphere during photosynthesis; hence, surplus carbon iv oxide is stored in the plants to help in growth and development. When we cut trees, their stored CO2 gets emitted to the atmosphere, which contributes to global warming.

Trees also help in regulating regional rainfall which prevents floods and drought in the area, cutting down trees influences the rainfall patterns globally. Deforestation also leads to changes in the landscape and the earth’s surface’s reflectivity, which leads to increased absorption of energy from the sun that results in global warming leading to changes in climate patterns.


Food is a basic human need, but before you get it on your table, it goes through production, storage, processing, packaging, transportation, and preparation. Every stage of food production releases substantial amounts of greenhouse gases. Agriculture is one of the most common human causes of climate change through emissions of gases and the conversion of forests to agricultural land.

The modern agriculture practices and food production method using synthetic fertilisers are great contributors to greenhouse gas emissions, global warming, and climate change. The introduction of large scale farming has led to deforestation and machine intensive farming, which contributes to carbon emissions.

In livestock farming, ruminant animals digest their food through enteric fermentation that results in methane production; there are also substantial methane emissions from irrigated rice fields. Generally, agriculture contributes to climate change through deforestation, biodiversity loss, acidification of the oceans through agricultural chemical wastes, and accelerated soil erosion.


Although the industrial revolution, and industrialisation, has led to improved living conditions in various aspects, it is associated with adverse environmental effects that cause climatic changes. With recent innovations, human labour has been replaced with machinery that uses new sources of energy in the industries.

Manufacturing involves the use of large amounts of power and the alteration of natural systems; it is directly responsible for domestic emissions and indirect emissions through electricity and fuel use. The manufacturing operations are linked to direct greenhouse gas emissions, for instance, in the production of chemicals, iron, or steel, which are highly energy-intensive.

People are moving to urban areas in search of employment; urbanisation is another great contributor to climate change. It results in overcrowding, pollution, and poor sanitation; massive urbanisation can also lead to deforestation, emission of more greenhouse gases.

Increased commercialisation and industrialisation increase the use of fossil fuels leading to global warming and climate change.


Human emissions and activities have caused the highest percentage of global warming, which has resulted in climate change, in recent years. The global warming indicators are clear from increased temperature, humidity changes, sea level rising, showing that the land is warming up very fast due to fossil emissions, and thus changing the climate.

Any farmer can tell that the weather patterns have been altered, which is likely to affect food security worldwide. The fingerprints that humans have left on the environment through industrial activities and civilisation can be seen in the oceans, atmosphere, and the earth’s surface.

murat sw portrait
Murat Suner
Co-founder, Editorial Board Member, Author

Huge amounts of greenhouse gases lurk in the oceans, and could make warming far worse

Stores of methane and CO2 in the world’s seas are in a strange, icy state, and the waters are warming, creating a ticking carbon time bomb.

Scientists are finding hidden climate time bombs—vast reservoirs of carbon dioxide and methane—scattered under the seafloor across the planet.

And the fuses are burning.

Caps of frozen CO2 or methane, called hydrates, contain the potent greenhouse gases, keeping them from escaping into the ocean and atmosphere. But the ocean is warming as carbon emissions continue to rise, and scientists say the temperature of the seawater surrounding some hydrate caps is within a few degrees of dissolving them.

That could be very, very bad. Carbon dioxide is the most common greenhouse gas, responsible for about three-quarters of emissions. It can remain in the atmosphere for thousands of yearsMethane, the main component of natural gas, doesn’t stay in the atmosphere as long as CO2—about 12 years—but it is at least 84 times more potent over two decades.

The oceans absorb a third of humanity’s carbon dioxide emissions and 90 percent of the excess heat generated by increased greenhouse gas emissions; it’s the largest carbon sink on the planet. If warming seas melt hydrate caps, there’s a danger that the oceans will become big carbon emitters instead, with grave consequences for climate change and sea level rise.

“If that hydrate becomes unstable, in fact melts, that enormous volume of CO2 will be released to the ocean and eventually the atmosphere,” says Lowell Stott, a paleoceanographer at the University of Southern California.

The discovery of these deep ocean CO2 reservoirs, as well as methane seeps closer to shore, comes as leading scientists warned this month that the world is now surpassing a number of climate tipping points, with ocean temperatures at record highs.

The few CO2 reservoirs that have been found so far are located adjacent to hydrothermal vent fields in the deep ocean. But the global extent of such reservoirs remains unknown.

“It’s a harbinger, if you will, of an area of research that is really important for us to investigate, to find out how many of these kinds of reservoirs are out there, how big they are, and how susceptible they are to releasing CO2 to the ocean,” Stott says. “We have totally underestimated the world’s total carbon budget, which has profound implications.”

Jeffrey Seewald, a senior scientist at Woods Hole Oceanographic Institution who studies the geochemistry of hydrothermal systems, questioned the magnitude of hydrate-capped reservoirs.

“I don’t know how globally significant they are as most hydrothermal systems that we know of are not associated with large accumulations of carbon, though there’s still a lot to be explored,” he says. “So I would be a little careful about suggesting that there are significant accumulations of CO2 that are just waiting to be released.”

A threat closer to home

Other scientists are far more concerned about potential climate time bombs much closer to home—methane hydrates that form on the shallower seafloor at the margins of continents.

Hydrothermal vents like this one can have reservoirs of liquid CO2 nearby, kept in place by icy hydrate caps. If those caps melt, the carbon could seep into the ocean, and ultimately into the atmosphere.


For one thing, there apparently are a lot of them. Between 2016 and 2018, for instance, researchers at Oregon State University and the National Oceanic and Atmospheric Administration (NOAA) deployed a new sonar technique to discover 1,000 methane seeps off the Pacific Northwest coast of the United States.

In contrast, just 100 had been identified between 2015 and the late 1980s, when scientists first stumbled across methane deposits. There are likely many more to be located, given that as of 2018, researchers only had mapped 38 percent of the seafloor between Washington State and Northern California.

“Because a lot of methane is stored on the continental margins in relatively shallow water, the effects of ocean warming will get to it sooner and potentially destabilize the methane hydrates that are present in the sediment,” says Dave Butterfield, a senior research scientist and hydrothermal vent expert at NOAA’s Pacific Marine Environmental Laboratory in Seattle.

He noted that these methane seeps likely constitute a far larger global reservoir of greenhouse gases than pools of carbon dioxide under the deep ocean floor.

“This idea is that if you destabilize the methane hydrates, that methane would be injected into the atmosphere and cause more extreme global warming,” says Butterfield, who in 2003 was part of an expedition that discovered a hydrate-capped reservoir of liquid CO2 at a hydrothermal system on the Mariana Arc in the Pacific.

Stott and colleagues earlier this year published a paper presenting evidence that the release of carbon dioxide from hydrothermal seafloor reservoirs in the eastern equatorial Pacific some 20,000 years ago helped trigger the end of the last glacial era. And in a new paper, Stott finds geological indications that during the end of Pleistocene glaciations, carbon dioxide was released from seafloor reservoirs near New Zealand.

The spike of atmospheric temperatures during previous periods when ice ages were ending mirrors today’s rapid rise as a result of greenhouse gas emissions. While the oceans have long been suspected as significant contributors to ancient global warming, the prevailing consensus was that the CO2 was released from a layer of water resting deep in the ocean. But research from Stott and other oceanographers over the past decade points to a geological culprit.

Like a needle in a haystack

Take the hydrate-capped liquid CO2 reservoir found by Butterfield and his colleagues on a volcano in the Pacific. They calculated that the rate that liquid CO2 bubbles were escaping the seafloor equaled 0.1 percent of the carbon dioxide emitted on the entire Mid-Ocean Ridge. That may seem like a small amount, but consider that the CO2 is escaping from a single, small site along a 40,390 mile-long system of submerged volcanoes that rings the planet.

“That’s an astonishing number,” says Stott.

Scientists believe such reservoirs can be formed when volcanic magma deep beneath the ocean floor interacts with seawater to produce superheated fluids rich in carbon or methane that rise toward the surface. When that plume collides with cooler water, an ice-like hydrate forms that traps the carbon or methane in subsurface sediments.

This newly discovered methane seep contained two different phases of methane: gas (bubbles) and solid form (hydrate, methane frozen in water). It is a rare occurrence to observe solid hydrates above the sediment like this. Typically these formations are buried under sediment layers.


The risk the reservoirs pose depends on their location and depth. For example, rising ocean temperatures could in coming years melt a hydrate capping a lake of liquid CO2 in the Okinawa Trough west of Japan, according to Stott. But the absence of upwelling currents there means a mass release of carbon dioxide at a depth of 4,600 feet would likely acidify the surrounding waters but not enter the atmosphere for an extremely long time.

Stott notes that finding CO2 and methane reservoirs in the deep ocean is a “needle and haystack situation.”

But in a paper published in August, scientists from Japan and Indonesia revealed that they had detected five large and previously unknown CO2 or methane gas reservoirs under the seafloor in the Okinawa Trough by analyzing seismic pressure waves generated by an acoustical device. Since those waves travel more slowly through gas than solids under the seafloor, the researchers were able to locate the reservoirs. The data indicates that hydrates are trapping the gas.

“Our survey area is not broad, so there could be more reservoirs outside of our survey area,” Takeshi Tsuji, a professor of exploration geophysics at Kyushu University in Japan and a co-author of the paper, says in an email.

Lake methane emissions should prompt rethink on climate change

Global methane cycle should be reconsidered in light of new research

December 4, 2019
Swansea University
Study sheds new light on the impact of natural methane production on global climate change assessments.

A new study from Swansea University has given new insights into how the greenhouse gas methane is being produced in the surface waters of lakes, which should signal a rethink on the global methane cycle.

After carbon dioxide, methane is the second most important carbon-based greenhouse gas and its continuous increase in the atmosphere is a global climate threat.

Conventional research, including the assessments by the Intergovernmental Panel on Climate Change (IPCC), has suggested that methane is produced naturally in oxygen-depleted environments such as swamps and wetlands. However the result of this new study, which is published in Nature Communications has now challenged these previous assessments.

The research team from the University’s College of Science analysed Lake Stechlin in north-eastern Germany and found that a significant amount of methane was being produced there in the well-oxygenated surface layer.

It was also discovered that as the methane gas is produced at the surface in direct contact with air, the levels of emissions that travel directly into the atmosphere are also significant.

The researchers also predicted that emissions from these surface waters are likely to increase with the lake size, and could account for over half of surface methane emission for lakes larger than one square kilometer.

Professor Kam Tang, of Swansea University’s Department of Biosciences said: “Our research shows that well oxygenated lake waters are an important, but long overlooked, source of methane emissions to the atmosphere. These novel findings open new avenues for methane research and support a more accurate global assessment of this powerful greenhouse gas.”

Lead author of the study, Marco Günthel said: “Methane emission in lakes is based on a complex network of biochemical and physical processes, some of which are still poorly understood. I hope our study will stimulate more research on this topic as it is needed to fully understand the global methane cycle and to improve climate change predictions.”

Story Source:

Materials provided by Swansea UniversityNote: Content may be edited for style and length.

Journal Reference:

  1. Marco Günthel, Daphne Donis, Georgiy Kirillin, Danny Ionescu, Mina Bizic, Daniel F. McGinnis, Hans-Peter Grossart, Kam W. Tang. Contribution of oxic methane production to surface methane emission in lakes and its global importanceNature Communications, 2019; 10 (1) DOI: 10.1038/s41467-019-13320-0

Cite This Page:

Swansea University. “Lake methane emissions should prompt rethink on climate change: Global methane cycle should be reconsidered in light of new research.” ScienceDaily. ScienceDaily, 4 December 2019. <>

New Zealand begins genetic program to produce low methane-emitting sheep

‘Global first’ project will help tackle climate change by lowering agricultural greenhouse gases

Sheep outside the city of Christchurch.
 The New Zealand livestock industry has begun a ‘global first’ program to breed low methane-emitting sheep. Photograph: Carly Earl/The Guardian

The New Zealand livestock industry has begun a “global first” genetic program that would help to tackle climate change by breeding low methane-emitting sheep.

There are about six sheep for each person in New Zealand, and the livestock industry accounts for about one-third of the country’s total greenhouse gas emissions.

The livestock industry’s peak body, Beef and Lamb New Zealand, already uses a measure called “breeding value” to help breeders select rams with characteristics they want to bolster within their flocks. Within two years breeders will be able to select rams whose traits include lower methane emissions.

“Farmers are more interested than I anticipated,” said a stud breeder, Russell Proffit. His family has been producing rams for more than 40 years.

“I’ve undertaken the [methane] measurements because I believe an animal that is healthy and doing well should produce less methane and I wanted to test that.

“I don’t know if that’s the case yet, but either way breeding for less methane complements what we are working to achieve on our stud. That is, more robust rams that require [fewer] inputs and make less demand on the environment.”

Breeders who want to produce low-methane rams will need to measure a portion of their flock in an accumulation chamber, where their gas emissions are measured. Sheep spend 50 minutes in the chamber, and must be measured twice with an interval of more than 14 days.

The resulting data is used alongside other genetic information to calculate a “methane breeding value”.

The pastoral greenhouse gas research consortium, which is jointly funded by the agricultural sector and the government, said the concept was to take advantage of variations in levels of methane emissions and research that found the differences were passed on to the next generation.

“This is a global first for any species of livestock,” the consortium’s general manager, Mark Aspin, said.

“Launching the methane breeding value gives New Zealand’s sheep sector a practical tool to help lower our agricultural greenhouse gases. This is significant. Up until now, the only option available to farmers wanting to lower their greenhouse gas emissions has been to constantly improve their overall farming efficiency.

“This takes us a step further – towards actually lowering sheep methane emissions, in keeping with the sector’s commitment to work towards reducing its greenhouse emissions.”

Progress via breeding could be about 1% a year, but it would be cumulative and have no negative impact on farm productivity.

Aspin said amounts of feed were the biggest factor that contributed to methane emissions, and the consortium was working on three technologies that aimed to reduce amounts of methane generated by feed.

“So by breeding sheep that produce less methane per mouthful eaten – as other methane-reducing technologies come on stream – the influence of these sheep on the national flock’s methane production becomes compounding.”

Beef and Livestock New Zealand’s chief executive, Sam McIvor, said recent research of 1,000 farmers found that information about reducing greenhouse emissions was among farmers’ top five priorities.

No more fire in the kitchen: Cities are banning natural gas in homes to save the planet


SAN FRANCISCO – Fix global warming or cook dinner on a gas stove?

That’s the choice for people in 13 cities and one county in California that have enacted new zoning codes encouraging or requiring all-electric new construction.

The codes, most of them passed since June, are meant to keep builders from running natural gas lines to new homes and apartments, with an eye toward creating fewer legacy gas hookups as the nation shifts to carbon-neutral energy sources.

For proponents, it’s a change that must be made to fight climate change. For natural gas companies, it’s a threat to their existence. And for some cooks who love to prepare food with flame, it’s an unthinkable loss.

Natural gas is a fossil fuel, mostly methane, and produces 33% of U.S. carbon dioxide emissions from electricity generation, according to the U.S. Energy Information Administration. Carbon dioxide is the primary greenhouse gas causing climate change.

“There’s no pathway to stabilizing the climate without phasing gas out of our homes and buildings. This is a must-do for the climate and a livable planet,” said Rachel Golden of the Sierra Club’s building electrification campaign.

These new building codes come as local governments work to speed the transition from natural gas and other fossil fuels and toward the use of electricity from renewables, said Robert Jackson, a professor of energy and the environment at Stanford University in Palo Alto, California.

“Every house, every high-rise that’s built with gas, may be in place for decades. We’re establishing infrastructure that may be in place for 50 years,” he said.

These “reach” or “stretch” building codes, as they are known, have so far all been passed in California. The first was in Berkeley in July, then more in Northern California and recently Santa Monica in Southern California. Other cities in Massachusetts, Oregon and Washington state are contemplating them, according to the Sierra Club.

Some of the cities ban natural gas hookups to new construction. Others offer builders incentives if they go all-electric, much the same as they might get to take up more space on a lot if a house is extra energy-efficient. In April, Sunnyvale, a town in Silicon Valley, changed its building code to offer a density bonus to all-electric developments.

No more gas stoves?

The building codes apply only to new construction beginning in 2020, so they aren’t an issue for anyone in an already-built home.

Probably the biggest stumbling block for most pondering an all-electric home is the prospect of not having a gas stove.

“It’s the only thing that people ever ask about,” said Bruce Nilles, who directs the building electrification program of the Rocky Mountain Institute, a Colorado-based think tank that focuses on energy and resource efficiency.

Roughly 35% of U.S. households have a gas stove, while 55%have electric, according to a 2017 kitchen audit by the NPD Group, a global information company based in Port Washington, New York.

For at least a quarter of Americans, it doesn’t matter either way. They already live in houses that are all-electric, and their numbers are rising, according to the U.S. Energy Information Administration. That’s especially true in the Southeast, where close to 45% of homes are all-electric.

For the rest of the nation, natural gas is used to heat buildings and water, dry clothes and cook food, according to the EIA. That represents 17% of national natural gas usage.

But the number of natural gas customers is also rising. The American Gas Association, which represents more than 200 local energy companies, says an average of one new customer is added every minute.

“That’s exactly the wrong direction,” Nilles said.

States weigh climate change solutions

The nudge toward all-electric buildings is the type of shift Americans will begin to experience more and more in coming years. Last year, California’s governor signed an executive order directing state agencies to work toward making the entire state economy carbon-neutral by 2045.

California is not alone. New York, Hawaii, Colorado and Maine have economywide carbon-neutrality goals, and several more are debating them. More than 140 U.S. cities have committed to transitioning to carbon-neutral energy.

The natural gas industry rejects the notion that it should not be part of the nation’s energy future.

“The idea that denying access to natural gas in new homes is necessary to meet emissions reduction goals is false. In fact, denying access to natural gas could make meeting emissions goals harder and more expensive,” said American Gas Association President and CEO Karen Harbert.

The association calls the new zoning codes for new construction burdensome to consumers and to the economy. They also say it’s more expensive to run an all-electric home. A study by AGA released last year suggested that all-electric homes would pay $750 to $910 a year more for energy-related costs, as well as amortized appliance and upgrade costs.

But critics question AGA’s conclusions.

Amanda Myers, a policy analyst at Energy Innovation, a research nonprofit group focused on reducing greenhouse gas emissions, said AGA presumed high electricity rates because of unrealistically large increases in expected electricity use and made unusual assumptions for how any anticipated electric load growth might be met.

An analysis last year by the Rocky Mountain Institute found that in locations as diverse as Chicago, Houston and Providence, Rhode Island, all-electric new homes over a 15-year time frame could save residents as much as $260 a year compared with new homes with air conditioners powered by electricity and natural gas.

You’ll pry my cold, dead hands off my gas range

The selling point for getting away from natural gas may come from a type of electric range that, according to chefs, is just as good if not better than gas. As fundamentally attached as people might be to cooking with fire, induction stoves are making headway.

Long popular in Europe and increasingly trendy in the United States, induction cooktops are different from the kind of traditional electric range where coils become red-hot. Induction ranges use electromagnetic energy to directly heat pots and pans.

They are fast, energy-efficient and safe because there’s no open flame, and they are cool to the touch unless you’re a piece of metal.

As puts it, they’re “gentle enough to melt butter and chocolate, but powerful enough to bring 48 ounces of water to a boil in under three minutes.”

The downsides are that induction cooktops are more expensive than traditional electric stoves, generally a third to half more. They also work only with pans with steel or iron bottoms.

Professional chefs say modern induction ranges are comparable to gas. The Culinary Institute of America in Hyde Park, New York, America’s preeminent cooking school, trains its chefs on both induction and gas stoves because they will encounter both types and must know how to use them.

“Some of the finest restaurants in Europe are often out in mountainous areas or places where there isn’t gas. They cook on induction and that works just fine,” said Mark Erickson, a certified master chef at the institute.

Regular electric stoves aren’t a deal-breaker either, said Erickson, who lives in a townhouse with one and cooks on it every night.

“If I were given the chance and if it were a choice of gas or electric, I would choose gas because it’s what I’m used to,” he said. “But in all honesty, it’s not the end of the world.”

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Are we looking at the livestock industry's GHG emissions holistically—and can a new framework help turn livestock into a solution for climate change?

Chemical maker DSM sees strong demand for methane-reducing cow feed additive

AMSTERDAM (Reuters) – Dutch specialty chemicals company DSM is expecting strong demand for its feed additive which limits the amount of methane burped into the air by cows, its contribution to the global fight against climate change.

Methane has a much larger effect on global warming than carbon dioxide (CO2) and reducing methane emissions could buy time to confront the much bigger challenge of cutting the amount of CO2 released into the atmosphere.

“We see a lot of demand already, from food producers and farmers”, DSM’s Clean Cow program director Mark van Nieuwland told Reuters in an interview, even though the launch of the additive, Bovaer, is still more than a year away.

“Large (food) companies have clear climate targets, and they need farms to change to meet those. Also consumers are increasing pressure on farmers and many farmers themselves want to limit emissions.”

Swiss KitKat and Nescafe maker Nestle this month said it wanted to reduce greenhouse gas emissions to zero by 2050, while French dairy maker Danone has said it wants to halve its CO2 emissions by 2030.

Cows constantly burp up the powerful greenhouse gas methane but DSM says including Bovaer in a cow’s diet could cut these emissions by at least 30%.

“Giving this to only three cows will have the same effect as taking one car off the road”, Van Nieuwland said.

DSM expects to launch Bovaer in Europe either late next year or in early 2021. It is currently waiting for authorization from the European Union to label it as an environmentally beneficial product.


The company estimates that Bovaer has a potential global market value of 1 to 2 billion euros and aims to expand into other markets soon after the European launch.

DSM has made a profitable switch from bulk chemicals to sustainable food ingredients and materials, growing sales of animal feed products to around 30% of its 9 billion euros ($9.8 billion) in total sales last year.

“We have to deal with methane in the next 5 to 10 years if we want to limit the rise in temperatures to 1.5 degrees”, Van Nieuwland said.

Bovaer cuts methane emissions when mixed into a cow’s feed by inhibiting an enzyme in the digestion process which normally causes the release of the gas.

After ten years of research the Dutch company says it has dozens of global peer reviewed studies backing its claims and showing no effect on the health of cows or the milk they deliver.

The trial will run from November until February 2020, and the results are expected to be applicable throughout Europe, DSM said.

“This can have a real impact and we want to make it as big as possible”, Van Nieuwland said. “The faster we move, the better.”