Methane, a powerful greenhouse gas, is leaking from your stove even when it is not in use. In fact, most of the methane they leak happens while the stoves are not being used. Although individually, each stove doesn’t leak much of the gas, the effect adds up tremendously over the whole USA.
“Simply owning a natural gas stove, and having natural gas pipes and fittings in your home, leads to more emissions over 24 hours than the amount emitted while the burners are on,” says Stanford Professor of Earth Sciences Rob Jackson, co-author of the study.
The team measured the methane released from the cooking stoves in 53 homes in the state of California. They recorded the quantity of methane that leaked whenever the knobs of the stove were turned, in the moments before the gas lit on fire. They also recorded how much methane escaped unburned during cooking. However, the main advantage of this study over comparative ones is that it also measured how much methane was released when the stoves were not in use.
According to the results, a surprising 80% of the methane leaks recorded during the study were observed while the stoves were not in use. These came from loose couplings and fittings between the stove and gas distribution pipes. Eric Lebel, the study’s lead author, says that their results come to address the lack of data on “incomplete combustion from appliances,” offering up a valuable piece of the climate change puzzle.
The stoves and cooktops studied in this study belonged to 18 different brands, and varied in age from between 3 to 30 years old. Stoves using pilot lights leaked more than those equipped with an electronic sparker.
According to the measurements, the team estimates that around 1.3% of the gas used in a stove leaks into the atmosphere — which, individually, is a small quantity. Added up over the more than 40 million gas stoves in the U.S., however, this amounts to a significant quantity of greenhouse gas. Overall, the climate-warming effect of this quantity of methane would be equivalent to the emissions of 500,000 gasoline-powered cars.
Such leaks become important when considering the global push against greenhouse gas emissions. The E.P.A. estimates that buildings account for more than 10% of the greenhouse gas emissions in the USA.
The authors advocate that switching to electric stoves would help slash these emissions. It would also help in the broader sense that making a switch here would make people more comfortable to switching other, larger sources of domestic emissions such as the furnace, water heater, and clothes dryer.
That being said, they are aware that such a switch isn’t viable for many people, such as renters as those who can’t afford to purchase an electric stove. In these cases, there is a simple step everyone can take to limit methane emissions in their home:
“Pull the stove out from the wall and tighten the connectors to the stove and to the nearby pipes,” Jackson says.
In order to remove these emissions completely, however, the team underlines that the only real option is to switch to an electric stove entirely.
The paper “Methane and NOx Emissions from Natural Gas Stoves, Cooktops, and Ovens in Residential Homes” has been published in the journal Energy and Climate.
The issue of methane pollution might become an asset in the future, thanks to new technology that can transform this potent greenhouse gas into fish food.
Approaches to converting methane into fishmeal have already been developed, the authors note, but the economic uncertainty during the pandemic has prevented its use to promote food security on any meaningful scale. The new study analyzes the method’s economic viability today. The main takeaway of the research is that methane-to-fishmeal conversion is economically feasible for certain sources of the gas and that other sources can be made profitable with certain improvements.
The approach can also be of quite significant help against climate change, the team adds, and is capable of meeting all the global demand for fishmeal, further reducing the strain we’re placing on natural ecosystems.
“Industrial sources in the U.S. are emitting a truly staggering amount of methane, which is uneconomical to capture and use with current applications,” said study lead author Sahar El Abbadia, a lecturer in the Civic, Liberal and Global Education program at Stanford.
“Our goal is to flip that paradigm, using biotechnology to create a high-value product.”
Carbon dioxide is the best-known greenhouse gas, and currently the most abundant one in the Earth’s atmosphere. That being said, methane is another important player in our current climate woes. Methane is estimated to have 85 times the global warming potential of CO2 over a 20-year period, and at least 25 times as great a potential over a 100-year period. Methane also represents a direct hazard to public health as concentrations of this gas are increasing in the troposphere (the lower layer of the atmosphere, where people live). An estimated 1 million premature deaths occur worldwide, per year, due to respiratory illnesses associated with methane exposure.
The problem posed by methane is also increasing over time: the relative concentration of this gas in the atmosphere has been increasing twice as fast as that of CO2 since the onset of the Industrial Revolution, the team explains. Although there are natural sources of atmospheric methane, mostly through the decomposition of organic matter and from digestive processes, the lion’s share of that increase is owed to human-driven emissions.
Methanotrophs, bacteria that consume methane, have been explored as a potential solution in the past. If supplied with methane, oxygen, and certain nutrients, these bacteria produce a protein-rich sludge that can be used, among other things, to produce feedstock for fish farms. This process is already in commercial use by some companies; however, they are supplied by methane fed through gas distribution grids.
The authors note that capturing methane emissions — such as those from landfills, wastewater treatment plants, or leaked at oil and gas facilities — would be both cheaper and much more eco-friendly. Besides economic and environmental benefits, the shift from pumped to captured methane in the production of fishmeal would also help ensure humanity’s greater food security. The authors explain that seafood consumption has increased more than four times since the 1960s, with grave consequences for natural fish stocks.
Aquaculture (fish farms) now provide around half of the quantity of animal-sourced seafood consumed globally. Demand for seafood in the form of algae and animals is also estimated to double by 2050, the team adds, which will place increased strain on producers.
Against this backdrop, methane-sourced fish feed can represent an important asset towards food security in the future, and allow us to have the seafood we crave for minimal environmental impact.
Makes economic sense
In order to determine whether such efforts would also be economically-feasible, the team modeled several scenarios, each with a different source of methane used in the production of the fishmeal. These included natural gas purchased from commercial grids, as well as methane captured from relatively large wastewater treatment plants, landfills, and oil and gas facilities. For each scenario, they looked at a range of variables that would factor into a company’s bottom line, including the availability of trained labor and the cost of electricity used to keep the bioreactors running.
In the scenarios that involved methane capture from landfills and oil & gas facilities, the production cost for one ton of fishmeal would be $1,546 and $1,531, respectively. Both are lower than the 10-year average market price of such products, which sits at $1,600. In scenarios in which methane capture was performed at wastewater treatment plants, the cost per ton sat at $1,645, which is just slightly over the market average. However, the highest prices per ton were seen when methane was purchased directly from the commercial grid — $1,783 per ton.
Surprisingly enough, electricity was the single largest expense for all scenarios, representing around 45% of total costs on average. This means that areas with low electricity production costs could see significant decreases. The authors estimate that in states such as Mississippi and Texas, these costs would go down by around 20%, to an average of $1,214 per ton ($386 less than the 10-year average).
With certain improvements, such as bioreactors with more efficient heat transfer to reduce the need for cooling, production costs can be reduced even further. Even in the scenarios where wastewater treatment plants provided the methane, steps can be taken to reduce costs. For example, wastewater itself can be used as a source of nitrogen and phosphorus (key nutrients), as well as for cooling.
The team estimates that if manufacturers can bring the per ton production cost by 20%, there would be profits to be made even if all the supply of fishmeal today was covered using methane-produced materials with gas captured in the U.S. alone. With ever more reductions in cost per ton, such products could out-compete soybean and other crops for animal feed in general.
“Despite decades of trying, the energy industry has had trouble finding a good use for stranded natural gas,” said study co-author Evan David Sherwin, a postdoctoral researcher in energy resources engineering at Stanford. “Once we started looking at the energy and food systems together, it became clear that we could solve at least two long-standing problems at once.”
The paper “Displacing fishmeal with protein derived from stranded methane” has been published in the journal Nature Sustainability.
While CO2 is usually branded as the main villain in the climate crisis, there are other greenhouse gases out there that also have their fair share of responsibility. Methane, especially, is 80 times more potent than CO2 (although it’s much more short-lived). Now, a group of countries at the climate summit COP26 in the UK have drawn up a plan of action to reduce methane emissions as quickly as possible.
Over 100 countries have signed a commitment to reduce their methane emissions by 30% between 2020 and 2030. The initiative is spearheaded by the United States and the European Union and it covers two-thirds of the global economy and half of the main 30 methane emitters countries. China, Russia and India haven’t joined it, however.
The plan had been announced in September, but the US government and the EU had been working hard since then to raise the number of signatories and the momentum behind the pledge. Alongside commitments on deforestation and financing renewable energy, this could probably be one of the big things coming out of COP26, which started this week.
“We have to act now. We cannot wait for 2050; we have to cut emissions fast,” European Commission President Ursula von der Leyen said at the pledge launch event at COP26 in Glasgow. “Cutting back on methane emissions is one of the most effective things we can do to reduce near-term global warming … it is the lowest-hanging fruit.”
While non-binding, if the pledge is actually met it will prevent 0.2ºC of global warming by the middle of the century. It may seem it’s not a lot, but every 10th of a degree makes a big difference in terms of climate change. Some of the worst effects of the climate crisis can still be prevented if the global temperatures don’t keep rising.
Campaigners largely welcomed the announcement, and reactions were positive. Ani Dasgupta, CEO of the World Resources Institute (a global research non-profit organization), said the next step for countries is to put the pledge in motion, with policies to address methane emissions in sectors such as agriculture and energy. “Solutions to tackle methane are readily available and are cost-effective,” she added.
Still, there are plenty of questions about how this pact will actually be enforced. The signatory countries committed to “work together in order to collectively reduce methane emissions” and to taking “comprehensive domestic actions.” This means they don’t have to draw a list of policies to sign the pledge, which gives it limited transparency.
The role of methane
Methane is released into the atmosphere through different human activities, including the production of fossil fuels (coal, oil and gas), landfills, and agriculture. Livestock breeding is largely to blame, as manure from cows, sheep and pigs adds methane to the atmosphere. It’s a very powerful gas responsible for about 30% of global warming.
Methane emissions have risen significantly and are now higher than at any point in the past 800,000 years, the Intergovernmental Panel on Climate Change (IPCC), which groups leading climate scientists, said in its most recent assessment. The good news is that methane emissions are more short-lived than CO2 and tend to break down within a decade.
A report earlier this year by the UN Environment Program (UNEP) found that human-caused methane emissions can be reduced by 45% this decade. This would avoid 0.3% of global warming by 2045 and would put us a step closer to meeting the key goal of the Paris Agreement of climate change of limiting global temperature rise to 1.5ºC.
A record 2020heatwave triggered the release of fossil methane gas leaked from known rock formations in Siberia. Since methane is a potent greenhouse gas itself, researchers fear this could be part of a climate feedback loop: where more heat triggers more greenhouse gas emissions and even more heat.
Methane is the second most abundant anthropogenic greenhouse gas after carbon dioxide (CO2). It’s 25 times as potent as CO2 at trapping heat in the atmosphere and over the last two decades, its concentration has more than doubled. Most of this has come from fossil fuels (especially coal), cattle, rice paddies, and waste dumps.
Scientists have long been worried over the risk of a “methane bomb” — a rapid increase in the amount of methane released to the atmosphere — from thawing wetlands in Siberia’s permafrost. But now, a study by three German geologists is raising the alarm over increasing emissions from thawing rock formations as well.
While the thawing wetlands release microbial methane from the decay of the soil and the organic matter, the thawing limestone releases hydrocarbons and gas hydrates from reservoirs below (and within) the permafrost. These emissions are “much more dangerous” than what was previously believed, according to the researchers.
“We observed an increase in methane concentration starting last summer. This remained over the winter, so there must have been a steady steady flow of methane from the ground,” Nikolaus Froitzheim, who led the research, told The Guardian. “At the moment, these anomalies are not of a very big magnitude, but it shows there is something going on.”
The researchers said they don’t know yet how dangerous these methane releases are, mainly because of a lack of information on how fast the gas is released.
Climate-wise, things are already bad. But this could add even more fuel onto an already massive fire. That’s why the team calls on further research on the issue. If the planet’s temperature keeps growing, the release of additional methane could be the difference between catastrophe and apocalypse, they added.
A satellite analysis
For the study, the researchers worked with satellite data to measure methane concentrations in the Taymyr Peninsula and its surroundings in northern Siberia, which was affected by the world’s most extreme heatwave of 2020. They focused on two “conspicuous elongates areas of limestone – stripes up to 375 miles long and several miles wide.
There’s hardly any soil in the stripes, making the limestone crop out of the surface. As the rock formations warm up, they start to crack, releasing methane that was trapped inside. Concentrations of methane were elevated by about 5% during the heatwave. Additional tests showed the concentration remained as high in the spring of 2021 despite the return of low temperatures.
“It’s intriguing. It’s not good news if it’s right,” Robert Max Holmes, a senior scientist at the Woodwell Climate Research Center, who was not involved in the study, told the Washington Post. “Nobody wants to see more potentially nasty feedbacks and this is potentially one. If something in the Arctic is going to keep me up at night that’s still what it is.”
The scientists now plan to investigate their findings further and model calculations to find out how much and how fast natural gas may be released. Froitzhem said the estimated amounts of natural gas in the subsurface of North Siberia are huge. Releasing the methane accumulated there to the atmosphere could have severe consequences on the global climate, he added.
Lightning could have an important ecological function, a duo of new paper reports. According to the findings, such discharges play an important role in clearing gases like methane from the atmosphere.
As we all know, thunderbolt and lightning, very, very frightening. However, they also seem to be quite fresh. The immense heat and energy released by lightning bolts break apart nitrogen and oxygen molecules in the air, which mix into hydroxyl radicals and hydroperoxyl radical — OH and HO2, respectively. In turn, these highly reactive chemical compounds go on to alter the atmosphere’s chemistry, in particular jump-starting the processes that degrade greenhouse gas compounds such as methane.
“Through history, people were only interested in lightning bolts because of what they could do on the ground,” says William H. Brune, distinguished professor of meteorology at Penn State and co-author on both of the new papers. “Now there is increasing interest in the weaker electrical discharges in thunderstorms that lead to lightning bolts.”
Data for this research was collected by an instrument plane flown above Colorado and Oklahoma in 2012. The plane followed thunderstorms and lightning discharges in order to understand their effect on the atmosphere.
Initially, the team assumed that the spikes in OH and HO2 signals (atmospheric levels) their devices were picking up must be errors, so they removed them from the dataset to study at a later time. The issue was that the instrument recorded high levels of hydroxyl and hydroperoxyl in stretches of the cloud where there was no visible lightning. A few years ago, Brune actually took the time to analyze it.
Working with a graduate student and research associate, he showed that the spikes could be produced both by sparks and “subvisible discharges” in the lab. After this, they performed a fresh analysis of the thunderstorm and lightning data from 2012.
“With the help of a great undergraduate intern,” said Brune, “we were able to link the huge signals seen by our instrument flying through the thunderstorm clouds to the lightning measurements made from the ground.”
Planes avoid flying through the center of thunderstorms because it’s simply dangerous for them, Brune explains, but they can be used to sample the top portion of the clouds which spread in the direction of the wind — this area of a storm is known as ‘the anvil’. Visible lightning is formed in the part of the anvil near the thunderstorm core.
Most bolts never strike the ground, he adds. This lightning is particularly important for affecting ozone and some greenhouse gas in the upper atmosphere. While we did know that lightning can split water to form hydroxyl and hydroperoxyl, this is the first time it has actually been observed in a live thunderstorm.
The researchers found hydroxyl and hydroperoxyl in areas with subvisible lightning, but very little evidence of ozone and no signs of nitric oxide (which requires visible lightning to form) in these areas. If this type of lightning occurs routinely, its outputs of hydroxyl and hydroperoxyl should be included in atmospheric models (they are not, currently).
Both of these compounds interact with some gases like methane, breaking them down through chemical reactions, and preventing them from realizing their full greenhouse potential.
“Lightning-generated OH (hydroxyl) in all storms happening globally can be responsible for a highly uncertain but substantial 2% to 16% of global atmospheric OH oxidation,” the team explains.
“These results are highly uncertain, partly because we do not know how these measurements apply to the rest of the globe,” said Brune. “We only flew over Colorado and Oklahoma. Most thunderstorms are in the tropics. The whole structure of high plains storms is different than those in the tropics. Clearly, we need more aircraft measurements to reduce this uncertainty.”
The first paper “Extreme oxidant amounts produced by lightning in storm clouds” has been published in the journal Science.
The second paper, “Electrical Discharges Produce Prodigious Amounts of Hydroxyl and Hydroperoxyl Radicals” has been published in the Journal of Geophysical Research: Atmospheres.
Even when you’re done with an oil well, you’re not really done with it. Idle wells could still be leaking methane, a potent greenhouse gas, into the atmosphere, according to a new study carried out on oil wells in Texas.
Amy Townsend-Small, an associate professor of geology and geography in UC’s College of Arts and Sciences, has been studying leaky oil wells for a few years, finding that some of them are still leaking methane years after the activity has been shut down. But this is the first time she was granted access to study wells on private land.
“Nobody has ever gotten access to these wells in Texas,” Townsend-Small said. “In my previous studies, the wells were all on public land,” Townsend-Small says.
There were reasons to suspect that things were not alright in Texas. A 2016 study by Townsend-Small found a similar issue in inactive wells she tested in Colorado, Wyoming, Ohio and, Utah, which leak methane equivalent to burning more than 16 million barrels of oil — and that’s according to conservative government estimates.
In Texas, things were just as bad, if not worse.
“Some of them were leaking a lot. Most of them were leaking a little or not at all, which is a pattern that we have seen across the oil and gas supply chain,” Townsend-Small said. “A few sources are responsible for most of the leaks.”
The average leaking rate was 6.2 grams per hour, although seven had methane emissions of as much as 132 grams per hour. If the same rate were to be consistent across all wells in Texas, it would be the equivalent of releasing 5.5 million kilograms of methane per year, the equivalent of burning 150 million pounds of coal.
In addition to the methane, Townsend-Small discovered another problem: five wells were leaking a brine solution onto the ground, in some cases creating large ponds, wreaking havoc on the nearby environment.
“I was horrified by that. I’ve never seen anything like that here in Ohio,” Townsend-Small said. “One was gushing out so much water that people who lived there called it a lake, but it’s toxic. It has dead trees all around it and smells like hydrogen sulfide.”
This isn’t the first time the problem was highlighted by researchers. Time and time again, studies have revealed that oil wells are leaking methane, and authorities are underestimating the problem. Across the US and Canada alone, there are millions of inactive oil wells, hundreds of thousands of which are undocumented. Many of these are improperly sealed and are continuously leaking methane into the atmosphere.
According to conservative estimates, these uncapped wells are responsible for 4% of the US total methane emissions, but the situation could be much worse, and those responsible for the wells are reluctant to offer external access to monitor the leaks. Even this study, wouldn’t have been possible without media organizations that wanted to explore the environmental impact of oil wells and arranged with property owners to allow Townsend-Small to carry out measurements. But there’s also some good news hidden in this study. The good news is that since a few of these wells are responsible for a majority of emissions, they could be prioritized and capped.
President Joe Biden’s stimulus plan includes $16 billion for capping abandoned oil and gas wells and mitigating abandoned mines. Inactive oil wells produce less methane than active ones, but it’s one way to reduce greenhouse gas emissions. With studies like this one, the more problematic ones could be prioritized. In addition, infrared camera inspections could help identify leaks and monitor wells.
Titan’s seas should be deep enough for a robotic submarine to wade through, a new paper explains. This should help pave the way towards our exploration of Titan’s depths.
Fancy a dip? Who doesn’t. But if you ever find yourself on Titan, Saturn’s biggest moon, you should stay away from swimming areas. A new paper reports that the Kraken Mare, the largest body of liquid methane on the moon’s surface is at least 1,000 feet deep near its center, making it both very deep and very cold.
While that may not be very welcoming to humans, such findings help increase our confidence in plans of exploring the moon’s oceans using autonomous submarines. It was previously unknown if Titan’s methane seas were deep enough to allow such a craft to move through.
“The depth and composition of each of Titan’s seas had already been measured, except for Titan’s largest sea, Kraken Mare—which not only has a great name, but also contains about 80% of the moon’s surface liquids,” said lead author Valerio Poggiali, a research associate at the Cornell Center for Astrophysics and Planetary Science (CCAPS).
Titan is a frozen moon that shines with a golden haze as sunlight glints on its nitrogen-rich atmosphere. Beyond that, however, it looks surprisingly Earth-like with liquid rivers, lakes, and seas sprawling along its surface. But these are not made of water — they’re filled with ultra-cold liquid methane.
The findings are based on data from one of the last Titan flybys made during the Cassini mission (on Aug. 21, 2014). During this flyby, the probe’s radar was aimed at Ligeia Mare, a smaller sea towards the moon’s northern pole. Its goal was to understand the mysterious “Magic Island” that keeps disappearing and then popping back up again.
Its radar altimeter measured the liquid depth at Kraken Mare and Moray Sinus (an estuary on the sea’s northern shore). The authors of the paper, made up of members from both NASA’s Jet Propulsion Laboratory and Cornell University, used this data to map the bathymetry (depth) of the sea. They did this by tracking the return time on the radar’s signal for the liquid’s surface and the sea bottom while taking into account the methane’s effect on the signal (it absorbs some of the energy from the radio wave as it passes through, in essence dampening it to an extent).
According to them, the Moray Sinus is about 280 feet deep, and the Kraken Mare gets progressively deeper towards its center. Here, the sea is too deep for the radar signal to pierce through, so we don’t know its maximum depth. The data also allowed us some insight into the chemical composition of the sea: a mix of ethane and methane, dominated by the latter. This is similar to the chemical composition of Ligeia Mare, Titan’s second-largest sea, the team explains. It might seem inconsequential, but it’s actually a very important piece of information: it suggests that Titan has an Earth-like hydrologic system.
Kraken Mare (‘mare’ is Latin for ‘sea’) is our prime choice for a Titan-scouting submarine due to its size — it is around as large as all five of America’s Great Lakes put together. We also have no idea why this sea doesn’t just evaporate. Sunlight is about 100 times less intense on Titan than Earth, but it’s still enough to make the methane evaporate. According to our calculations, this process should have completely depleted the seas in around 10 million years, but evidently, that didn’t happen. This is yet another mystery our space-faring submarine will try to answer.
“Thanks to our measurements,” he said, “scientists can now infer the density of the liquid with higher precision, and consequently better calibrate the sonar aboard the vessel and understand the sea’s directional flows.”
The paper “The Bathymetry of Moray Sinus at Titan’s Kraken Mare” has been published in the journal Journal of Geophysical Research: Planets.
Global emissions of methane, a powerful greenhouse gas, have reached the highest level on record. The main causes are the usual culprits: fossil fuels, livestock, and landfills.
Much of the methane produced today is released into the atmosphere when fossil fuels are mined and transported. However, but microbes also emit methane in low-oxygen environments. That’s why places with little or no oxygen such as wetlands, rice paddies, landfills, and the stomach of a cow are also sources of methane. Although methane isn’t as long-lived as carbon dioxide, it is far more potent, which makes it an important contributor to global heating.
If current trends continue, we could witness catastrophic heating in less than a century. The increase in the levels of methane, combined with other greenhouse gases such as carbon dioxide, is expected to lead to global warming of three to four degrees Celsius by 2100, the researchers suggested. This would trigger severe natural disasters such as droughts and heatwaves, affecting all the ecosystems on the Earth.
“This completely overshoots our budget to stay below 1.5 to 2 degrees of warming,” Benjamin Poulter, a research scientist at NASA’s Goddard Space Flight Center and one of the authors of the papers, told NBC, referring to the Paris Agreement, through which countries committed in 2015 to keep global heating within 1.5 or 2 degrees.
The findings were included in two papers published by researchers with the Global Carbon Project. They analyzed methane emissions from 2000 to 2017, the latest year with complete global data available, and found a record of 6000 million tons of methane released into the atmosphere in 2017. Emissions have risen by 9% since 2000.
To put it in simpler terms, this is equivalent to placing 350 million more cars on the world’s roads or doubling the total emissions of Germany or France. For Rob Jackson, one of the authors of the studies, the world “hasn’t turned the corner” on methane, and prospects are dire.
The main drivers
Throughout the study period, agriculture represented almost two-thirds of the methane emissions related to human activities — most of that coming from animal agriculture. Meanwhile, fossil fuels contributed to most of the remaining third. In 2017, methane emissions from agriculture rose 11% from the 2000-2006 average. Methane from fossil fuels also increased by 15% in the same period.
Africa, the Middle East, China, South Asia and Oceania saw the largest increase in methane emissions, according to the findings. In each of these regions’ emissions rose from 10 to 15 million tons per year during the study period. The US followed them closely, with an increase of 4.5 million tons in its emissions, mainly due to natural gas.
“Natural gas use is rising quickly here in the U.S. and globally. It’s offsetting coal in the electricity sector and reducing carbon dioxide emissions, but increasing methane emissions in that sector,” said Jackson. “We are emitting more methane from oil and gas well and leaky pipelines.”
Europe was the single region in which methane emissions have declined over the last two decades, mainly thanks to lower emissions from chemical manufacturing and growing efficiency from food production. Marielle Saunois of the Université de Versailles Saint-Quentin, authors of one of the papers, also highlighted the change in diets, with fewer people eating beef in Europe.
Addressing this problem won’t be easy, researchers warn. Reducing methane emissions will require cutting fossil fuel use and controlling fugitive emissions such as leaks from pipelines and wells, the researchers argued. At the same time, we will need to implement changes in the way we feed cattle, grow rice, and eat. The world has to eat less beef, replacing it with other products, Jackson argued.
The good news is that each one of us can do something about it, by being more mindful of what we eat and how much fuel we use — and we’d be wise to do so.
A report released in 2018 by the Intergovernmental Panel on Climate Change (IPCC), a global group of climate researchers, found that the planet has already warmed by 1 degree Celsius since the 19th century.
A large part of the United States’ energy comes from oil and natural gas pumped out of the ocean floor. Nearly all extraction currently takes place in the central and western Gulf of Mexico, where thousands of platforms operate in waters up to 6,000 feet deep.
Researchers from the University of Michigan decided to sample the air over the offshore oil and gas platforms to look at their environmental impact, discovering that the platforms are actually emitting twice as much methane, a powerful greenhouse gas, than previously thought.
The study found that oil and gas facilities in the Gulf of Mexico emit approximately half a teragram of methane each year, comparable with large emitting oil and gas basins. The effective loss rate of the produced gas is roughly 2.9%, similar to large onshore basins primarily focused on oil.
Offshore harvesting accounts for roughly one-third of the oil and gas produced worldwide, and these facilities both vent and leak methane. Until now, only a handful of measurements of offshore platforms have been made, and no aircraft studies of methane emissions in normal operation had been conducted.
Each year the Environmental Protection Agency (EPA) issues its U.S. Greenhouse Gas Inventory, but its numbers for offshore emissions are not produced via direct sampling. The research from the University of Michigan identified a set of reasons behind the discrepancy between their findings and the ones by the EPA.
There are errors in the platform counts done by the EPA, the researches claimed, having found 1.300 offshore facilities not incorporated in the inventory. At the same time, emissions from shallow-water facilities, especially those focused on natural gas, are higher than inventoried. Eric Kort, a University of Michigan associate professor of climate and space sciences and engineering, said EPA officials are already making adjustments to correct their count of offshore platforms operating in the Gulf of Mexico. But emissions estimates, particularly for shallow waters, still need adjustments.
“We have known onshore oil and gas production often emits more methane than inventoried. With this study we show that this is also the case for offshore production, and that these discrepancies are large,” Kort said. “By starting to identify and quantify the problem, with a particular focus on larger shallow water facilities, we can work towards finding optimal mitigation solutions.”
The researchers took their samples in 2018 using a small research plane with enough room for a pilot and passenger and scientific gear. Tubes along the wings of the plane drew in the air that was pumped to the equipment for analysis of the amount of methane included as well as wind speed.
In addition to 12 individual facilities, the flights also covered larger geographical areas. Flying downwind from clusters of 5 to 70 oil and gas facilities, and taking similar measurements, researchers could evaluate how well inventory estimates compare with large numbers of platforms.
As a pilot study, Kort said the research is promising but has gaps. Greater statistical sampling and identification of the cause of high emissions can guide mitigation and improve reported emissions. To further the work and fill in these gaps, new aerial sampling is in the works. The project, titled Flaring and Fossil Fuels: Uncovering Emissions & Losses (FUEL), will require more flights later over the next three years.
New research at the University of Rochester (UoR) says we’ve been severely underestimating the levels of methane humanity is emitting into the atmosphere via fossil fuels.
The findings are particularly worrying as although methane naturally breaks down quickly in the atmosphere (relative to CO2), it’s also a very powerful greenhouse gas, with a global warming potential (GWP) 104 times greater than CO2 over a 20-year time frame. Reducing methane emissions is critical in our effort to curb climate change, the team adds.
Too much of a bad thing
“Placing stricter methane emission regulations on the fossil fuel industry will have the potential to reduce future global warming to a larger extent than previously thought,” says lead author Benjamin Hmiel, a postdoctoral associate in the lab of Vasilii Petrenko, who is a professor of earth and environmental sciences at the UoR.
Methane is currently considered to be the second-largest contributor to global warming produced and released by human activity. Unlike CO2 (which ranks first), methane breaks down quickly — nine years on average, while CO2 can last for up to a century. This makes methane a more attractive target for short-term climate stabilization efforts, as any reductions in methane levels would translate into temperature stabilization much more quickly.
Hmiel explains that atmospheric methane comes from two sources: fossil methane and biological methane. Researchers distinguish between the two by looking at the nature of the carbon isotopes this molecule contains — carbon-14 for fossil methane (which was locked in fossil fuel deposits) and ‘regular’ carbon-13 for biological methane. Biological methane is released by all manner of biological activity; fossil methane is released either through geologically-exposed deposits (rare) or as a result of the extraction and exploitation of fossil fuels (which is much more common). Himel focused on this latter type.
“As a scientific community we’ve been struggling to understand exactly how much methane we as humans are emitting into the atmosphere,” says Petrenko, a coauthor of the study.
“We know that the fossil fuel component is one of our biggest component emissions, but it has been challenging to pin that down because in today’s atmosphere, the natural and anthropogenic components of the fossil emissions look the same, isotopically.”
The team collected ice cores from Greenland in order to establish a baseline atmospheric methane level before the onset of anthropogenic (man-made) factors. They melted the cores to extract the gas locked away in the ancient air bubbles they formed and studied its chemical composition.
Before the start of the Industrial Revolution in the 18th century, they found that virtually all the methane in the atmosphere was of biological origin. Things started to change after about 1870, when the fossil component began rising rapidly; they explain that this coincides with a sharp increase in fossil fuels at the time.
But the real finding was that levels of naturally released fossil methane are about 10 times lower than previously reported. Hmiel and his colleagues estimate that man-made fossil methane levels today are 25-40% (38-58 billion kgs) higher than previously estimated.
This may actually be good news. If we’re responsible for more of the methane in the atmosphere today, efforts to reduce our emissions would have an even better impact on the climate. If we reduce our emissions, that is.
“I don’t want to get too hopeless on this because my data does have a positive implication: most of the methane emissions are anthropogenic, so we have more control,” Hmiel concludes. “If we can reduce our emissions, it’s going to have more of an impact.”
The paper “Preindustrial 14CH4 indicates greater anthropogenic fossil CH4 emissions” has been published in the journal Nature.
Methane emissions are massively underreported by the industry, a new study using Google Street View cars found. Even the EPA estimate, which is much more realistic, is still three times lower than what researchers found.
“We took one small industry that most people have never heard of and found that its methane emissions were three times higher than the EPA assumed was emitted by all industrial production in the United States,” said John Albertson, co-author and professor of civil and environmental engineering. “It shows us that there’s a huge gap between a priori estimates and real-world measurements.”
The methane hotspots of continental USA. Image credits: NASA/JPL.
Although the world has made some progress in reducing our consumption of coal, the use of natural gas has grown in recent years, particularly due to increased shale gas extraction and a general perception that gas isn’t as dirty as coal.
There is some truth to that idea. In a new, efficient power plant, natural gas emits 50 to 60 percent less carbon dioxide (CO2) when compared with emissions from a typical new coal plant. It’s still bad, just not as bad as coal. But if emissions are overlooked at any point in the extraction, processing, and distribution process, it could drastically change the math. A new study seems to indicate that just that — except it’s not about CO2, but methane.
While CO2 can affect the atmosphere for centuries or even millennia,methane only persists for about 12 years. However, it’s still an important consideration when it comes to climate change, particularly in the more immediate future. CO2 is usually painted as the bad boy when it comes to global warming, but as a greenhouse gas, methane is 30 times more powerful than CO2.
The globally averaged concentration of methane in Earth’s atmosphere has increased by about 150 percent since the start of the Industrial Revolution, and while most of the attention is aimed at carbon dioxide, methane is also closely monitored. Though, it might not be monitored closely enough.
For this study, a Google Street View vehicle equipped with a high-precision methane sensor traveled public roads near six representative fertilizer plants in the US to quantify “fugitive methane emissions” — inadvertent losses of gas to the atmosphere. These fugitive emissions can happen due to leaks and incomplete chemical reactions during the fertilizer production process. As soon as researchers found a plume of high values, they would drive dozens of laps around it with the car, to take detailed measurements.
The team found that, on average, 0.34% of the gas used in the plants is emitted to the atmosphere. If the figure is a representative average, then the entire industry would have total annual methane emissions of 28 tons — 100 times higher than the industry’s self-reported estimate. Even the EPA’s estimate (8 tons) is much too conservative.
The fact that methane emissions are so heavily underestimated is concerning and calls for further investigation, the researchers conclude.
A group of researchers representing several institutions in Denmark, with colleagues from Sintex and Haldor Topsoe, has developed an electrified methane reformer that produces far less CO2 than conventional steam-methane reformers. The method could allow us to produce hydrogen and hydrogen fuel much more cleanly in reformers, and could also be used in tandem with other recent research to help us mitigate global warming.
Less gas for your buck
Global production of hydrogen is around 60 million tons per year. The gas is vital for the production of methanol and ammonia for fertilizer (which is its primary use so far), and could become the bedrock of a hydrogen-fuel economy. However, it’s also a pretty dirty business: some estimates place around 3% of the world’s current CO2 emissions on the back of steam-methane reformers, our primary source of hydrogen.
A steam-methane reformer is a very large implement, think of it as a simplified and scaled-down oil refinery, which is used to extract hydrogen from methane gas. The process involves burning natural gas to heat up a methane-water mixture, under pressure, ‘cooking’ it into syngas — a mix of carbon monoxide and hydrogen. Needless to say, this produces quite a lot of CO2, which is released into the atmosphere. Additional CO2 is also produced inside the reformer as an incomplete reaction product.
The team aimed to reduce the hydrogen industry’s carbon footprint by devising an electricity-based methane reformer. This device, they report, is significantly smaller (one hundred times smaller, in fact) than a traditional reformer and far cleaner. It uses electricity to heat up the water-methane mixture, which removes CO2 emissions associated with the burning of natural gas. The approach also results in a much more even and easily-controlled heating of the water-methane mix, slashing the amount of CO2 produced inside the reforming chamber.
If powered by electricity generated from a renewable resource, the team points out, the electric reformer would reduce the footprint of hydrogen production dramatically. If all the steam-methane reformers in the world were replaced by electrified systems, they add, the world would see a 1% drop in CO2 emissions.
We’ve also talked recently about a somewhat unorthodox idea to help us fight climate warming: replacing anthropic methane in the atmosphere with CO2. The authors of that study already propose degrading methane through heat into CO2. Coupled with the new electric reformer, we could also generate hydrogen for use as fuel or fertilizers.
The paper “Electrified methane reforming: A compact approach to greener industrial hydrogen production” has been published in the journal Science.
A relatively simple but counterintuitive approach aims to fight climate change — by actually increasing CO2 emissions.
Image via Pixabay.
Fighting climate warming with greenhouse emissions might sound like it won’t work, because it wouldn’t. The team that authored this study, however, doesn’t just aim to increase CO2 levels in the atmosphere. Rather, it proposes that we degrade methane, a much more potent greenhouse gas, into CO2 — the swap, they write, would be a net benefit for world climate.
The study proposes zeolite, a crystalline material that consists primarily of aluminum, silicon, and oxygen, as a key material to help us scrub methane emissions.
The lesser of two evils
“If perfected, this technology could return the atmosphere to pre-industrial concentrations of methane and other gases,” said lead author Rob Jackson, the Michelle and Kevin Douglas Provostial Professor in Earth System Science in Stanford’s School of Earth, Energy & Environmental Sciences.
Much more relevant to the current situation, the team notes, is that this process is also profitable. Boiled down, the idea is to take methane from sources where it’s difficult or expensive to eliminate — from cattle farms or rice paddies, for example — and degrade it into CO2.
Methane concentrations in the atmosphere are almost two-and-a-half times higher today than before the Industrial Revolution, the team explains. There’s a lot less methane than CO2 in the air, granted, but methane is 84 times more potent than CO2 as a climate-warming gas over the first 20 years after its release. Finally, some 60% of atmospheric methane today is directly generated by human activity.
Most climate strategies today focus on CO2, which is understandable. It’s the largest (by quantity) greenhouse gas we emit, and it’s easy to relate to — we breathe out CO2, cars belch out CO2, factories do too, and plants like to munch on it. But scrubbing other greenhouse gases, particularly methane due to its enormous greenhouse effect, could be useful as a complementary approach, the team explains. Furthermore, there’s just so much CO2 already floating around — and we keep pumping it out with such gusto — that CO2-removal scenarios often call for billions of tons to be removed, over decades, which would still not get us to pre-industrial levels
“An alternative is to offset these emissions via methane removal, so there is no net effect on warming the atmosphere,” said study coauthor Chris Field, the Perry L. McCarty Director of the Stanford Woods Institute for the Environment.
Methane levels could be brought back down to pre-industrial levels by removing about 3.2 billion tons of the gas from the atmosphere, the team notes. Converting all of it into CO2 would be equivalent to a few months of global industrial emissions, which is relatively little, but would have an outsized effect: it would eliminate approximately one-sixth of all causes of global warming to date.
So why then didn’t anybody think of this before? Well, the thing is that methane is hard to scrub from the air because its overall concentrations are so low. However zeolite, the team explains, is really really good at capturing the gas due to its “porous molecular structure, relatively large surface area and ability to host copper and iron,” explains coauthor Ed Solomon, the Monroe E. Spaght Professor of Chemistry in the School of Humanities and Sciences. The whole process could be as simple as using powerful fans to push air through reactors full of zeolite and catalysts. This material can then be heat-treated to form and release carbon dioxide gas.
Now let’s talk money. If market prices for carbon offsets rise to $500 or more per ton this century as predicted by most relevant assessment models, the team writes, each ton of methane removed from the atmosphere could be worth more than $12,000. A zeolite reactor the size of a football field could thus produce millions of dollars a year in income while removing harmful methane from the air. This is very fortunate as, in my experience, nothing motivates people to care about the environment quite like making money from saving it.
In principle, the researchers add, the approach of converting a more harmful greenhouse gas to one that’s less potent could also apply to other greenhouse gases.
The paper “Methane removal and atmospheric restoration” has been published in the journal Nature Sustainability.
When researchers first discovered methane on Mars more than a decade ago, it was a huge deal. The presence of methane could enhance habitability and may even be a signature of life but it was never really confirmed independently — until now.
Curiosity’s landing site in Gale Crater. Image credits: NASA/JPL.
Marco Giuranna and colleagues at the National Institute of Astrophysics in Rome, Italy, presented spacecraft-based spectrometer observations of methane in the Martian atmosphere near Gale Crater, the landing site of the Curiosity rover. Using data Mars Express, a space exploration mission being conducted by the European Space Agency, they found results which confirm Curiosity’s measurements. This independent measurement offers much more confidence
Using numerical modeling and geological analysis, they also propose that the methane is released in a region of geological faults, pinpointing a promising location for future investigations into the origin of methane on Mars.
“This work presents the first independent confirmation of methane detection on Mars and the first synergistic approach to the search for potential sites of methane release, integrating orbital and ground-based detections with Martian geology and atmospheric simulations (using gas emission scenarios based on terrestrial seepage data). This approach provides a template for future efforts aimed at locating sites of methane release from the subsurface on Mars. While this work relies on the hypothesis of a surface release, other explanations remain possible, but given a surface release, our work provides the first constraints for source locations,” researchers write.
Previous detections were rightfully questioned. Earth-based observations can find it very difficult to discriminate between telluric and Martian features and the spectral resolution is also very low. Meanwhile, Curiosity rover data can also be questioned as the methane might potentially come from the rover itself — although that possibility was previously ruled out by the Curiosity team. The main problem was that none of the positive detections have ever been confirmed.
This is the first time that a methane detection on Mars has been confirmed independently, so this adds a whole new level of certainty.
But what does this mean?
Regional map. The yellow triangle is Curiosity’s location, black line around that is the location of methane detection. The area was split into grid squares to assess the likelihood of methane sources. The eastern blocks were found to be the most likely sources. Image credits: Giuranna et al.
Methane is a chemical compound closely associated with microbial life, but it isn’t necessarily biological in nature. There’s a very good chance that the methane is generated geologically, and this is what this new paper also suggests.
Geological faults (planar fractures and displacements) have been associated with methane emissions on Earth, making them a likely culprit. The exact source of the methane remains to be identified in future missions — as does the existence of life on Mars.
The study “Independent confirmation of a methane spike on Mars and a source region east of Gale Crater” has been published in Nature.
Policy meant to reduce emissions from coal mines in China is falling far from the mark, new research reveals.
Canaries were once regularly used in coal mining as an early warning system. Toxic gases such as carbon monoxide and methane in the mine would kill the bird before affecting the miners. Image credits Michael Sonnabend / Flickr.
Chinese coal mining operations have produced increasing levels of methane emissions since 2010, a new study reports. These results show that the government’s efforts to curb emissions aren’t working as intended.
Business as usual
Back in 2010, the Chinese government passed new policy meant to reduce emissions of methane produced during the mining process to limit the industry’s ecological footprint. Companies were required to either utilize or flare (burn) methane released inside coal mines. Carbon dioxide (CO2), the best-known greenhouse gas, persists in the atmosphere for longer than methane (CH4). However, methane (CH4) is the second-ranking anthropogenic greenhouse gas, with a global warming potential 28 times greater than that of carbon dioxide (CO2) on a mass basis.
The move was quite ambitious. China’s twelfth Five Year Plan specified that 5.6 teragrams (one teragram equals one million kilograms, or one thousand tons) of the methane produced by the country’s coal mines should be tapped or burned by 2015. Targets for 2020 called for even higher quantities to be used in such ways. China’s government also called for coal use in the national energy mix to decrease from 64% (in 2015) to about 58% by 2020 and scaled back plans for new coal power plants — all of which should indirectly reduce methane emissions by reducing coal use.
A new paper led by Scot Miller, an Assistant Professor at the Johns Hopkins University, Maryland, United States, estimated methane emissions in China using satellite data from between 2010 and 2015. According to their data, the country’s methane emissions didn’t dip under the new policy — instead, they increased.
The team estimates that emissions rose by roughly 1.1 teragrams of methane per year during the study period, the team estimates. Overall, methane emissions followed a business-as-usual scenario, they say. The team also notes that coal production increased steadily over the study period, while cattle counts and rice production (two other major sources of methane emissions) remained relatively steady. The country’s coal mining industry contributes around one-third (roughly 33%) of its total anthropogenic methane emissions, the team estimates.
Pooling all this data together suggests that the Chinese government’s efforts failed to produce a detectable decrease or decline in methane emissions associated with coal production, the team writes. They also conclude that it’s unlikely the country met the ambitious regulatory target it set for 2015.
The paper “China’s coal mine methane regulations have not curbed growing emissions” has been published in the journal Nature.
Termite mounds have an ingenious built-in methane filtering system. The insects’ approach might help inspire new ways for humans to keep methane out of the atmosphere.
Image credits hbieser / Pixabay.
Termites, like cattle and other grass-feeding animals, work together with special bacteria in their gut to break down food. It’s a good deal — they get to dine on plants most competition can’t stomach — but it does produce a lot of methane during digestion.
It isn’t really much of a problem for the mound — but it is for us. Methane is about 30 times more potent a greenhouse gas than carbon dioxide and a big driver of climate change. Termites are responsible for generating an estimated 1-3% of global methane emissions, around 20 million tonnes of the gas, each year. However, that’s a lot less than they’re actually producing. Their mounds come with built-in filtration systems that scrub methane before it reaches the atmosphere, a new paper reports.
A team of researchers led by Dr. Philipp Nauer from the School of Ecosystem and Forest Sciences at the University of Melbourne reports that around half of all methane emitted from termites is broken down by bacteria within the mounds and underlying soil. Methane is a good source of energy and, as such, quite valuable to life, explains co-author Stefan Arndt, a Professor at the University of Melbourne. A group of bacteria called methanotrophs live in the soil and consume methane as their primary source of energy.
“They are in your garden soil, in your city soil, in the forest, they are even in agricultural soils,” says Professor Arndt. “Logic would tell you there should be these methanotrophic bacteria also in the termite mounds, because they are everywhere.”
Dr. Nauer’s team had to develop new techniques in order to accurately map how methane is processed in a mound. This task was especially difficult, he recounts, as “you have all three processes in the methane cycle – production, transportation, and consumption – at the same time and place,” making it hard to track individual steps in the process.
“In soils with a methane source, for example rice paddies, you often have separate zones where you have methane production or methane consumption, with transport between them, but in termite mounds it’s a lot more complex. You don’t know where the termites are, so you don’t know where the production is at.”
Other difficulties arose from the properties of the mounds themselves. They’re never uniform structures, they’re porous (but not as porous everywhere), and they’re riddled with complicated networks of channels and chambers. As such, it’s exceedingly difficult to estimate the total volume of gas inside a mound. And the team needed to know exactly that exact figure in order to complete their study.
Measuring net methane emissions to the atmosphere is “relatively easy”, according to Dr. Nauter — just put a container over the mound and measure how much gas comes out. In order to estimate the mounds’ volumes, the team “developed a photogrammetric record, where we took photos at many different angles and then calculated the 3-D structure with software.”
To see inside the mounds, Dr. Nauer appealed to the local medical community. He planned on taking a CT scan of one such mound to get an estimate of how much open volume it holds. He assumed medical staff “would say no, or [that there] was a waiting list of several months.”
“Instead there was this radiographer, the first one I called, who just said, ‘Oh cool, termite mounds. I always wanted to do this. Bring them in’.”
The final step was to see how much methane the bacteria in the mound could consume. They injected one mound with a known amount of methane and ‘tracer gas’ (argon), then drew it out and measured how much methane was gone. On average, half of all the methane was consumed by methanotrophs. This figure was calculated from 29 mounds made by three different termite species, the team explains.
“Some mounds were actually consuming methane from the atmosphere, and some mounds were massive sources, but throughout this whole scale, the percent of the methane that gets consumed is very stable,” says Dr. Nauer.
“The range was 20 to 80 per cent, but most mounds have an oxidation fraction of around 40 to 60 percent, so we think this 50 percent is something that is inherently built in, because the system sort of buffers itself. If you have more production, you get more consumption.”
The team hopes to use their findings to design new systems to keep our own methane emissions in check. The real challenge “is upscaling,” Dr. Nauer admits.
The paper “Termite mounds mitigate half of termite methane emissions,” has been published in the journal Proceedings of the National Academy of Sciences.
Turns out humanity doesn’t have a monopoly on self-destructive behaviors.
Sólheimajökull glacier, Iceland. Image credits Chris / Flickr.
One glacier in Iceland is putting out large quantities of methane, a powerful greenhouse gas, a new study reports. The Sólheimajökull glacier — which flows from the active, ice-covered volcano Katla — generates and releases about 41 tonnes of methane (through meltwater) each day during the summer months. That’s roughly equivalent to the methane produced by 136,000 cows, the team adds.
“This is a huge amount of methane lost from the glacial meltwater stream into the atmosphere,” said Dr. Peter Wynn, a glacial biogeochemist from the Lancaster Environment Centre and corresponding author of the study.
“It greatly exceeds average methane loss from non-glacial rivers to the atmosphere reported in the scientific literature. It rivals some of the world’s most methane-producing wetlands; and represents more than twenty times the known methane emissions of all Europe’s other volcanoes put together.”
Methane is a much more powerful greenhouse gas than carbon dioxide (CO2) — 28 times more powerful, to be exact. Knowing exactly how much of it makes its way into the atmosphere thus becomes very important, both from an environmentalist and a legal point of view (for cap-and-trade or similar systems).
Whether or not glaciers release methane has been a matter of some debate. On the one hand, they’re almost perfectly suited for the task: they bring together organic matter, water, and microbes in low-oxygen conditions (all very conducive to methane), capping them all off with a thick layer of ice to trap the gas. On the other hand, nobody had ever checked to make sure. So the team decided to take the matter into their own labs.
They visited the Sólheimajökull glacier in Iceland to retrieve samples from the meltwater lake it forms. The team then measured methane concentrations in the samples and compared them to methane levels in nearby sediments and other rivers, to make sure they weren’t picking up on environmental methane emissions from the surrounding area.
“The highest concentrations were found at the point where the river emerges from underneath the glacier and enters the lake. This demonstrates the methane must be sourced from beneath the glacier,” Dr. Wynn explains.
Subsequent spectrometry analyses revealed that the methane was generated by microbial activity underneath the glacier. However, the volcano also has a part to play here. It doesn’t generate methane directly, but it “is providing the conditions that allow the microbes to thrive and release methane into the surrounding meltwaters,” explains Dr. Wynn.
The thing is that methane really likes oxygen. It likes it so much, in fact, that whenever the two meet they hook up into CO2. What generally happens with glaciers is that oxygen-rich meltwaters seep to the bottom and convert any methane trapped there into CO2. At Sólheimajökull, however, most of the oxygen in this meltwater is neutralized by gases produced by the Katla volcano. The methane remains unaltered, dissolves into the water, and escapes from under the glacier unscathed.
“Understanding the seasonal evolution of Sólheimajökull’s subglacial drainage system and how it interacts with the Katla geothermal area formed part of this work”, said Professor Fiona Tweed, an expert in glacier hydrology at Staffordshire University and co-author of the study.
Heat from Katla also keeps the environment cozy for the microbes living under the glacier and may “greatly accelerate the generation of microbial methane, so in fact you could see Katla as a giant microbial incubator,” adds Dr. Hugh Tuffen, a volcanologist at Lancaster University and co-author on the study.
Such active, ice-bound volcanoes and geothermal systems are abundant in both Iceland and Antarctica. The present paper suggests that these systems can have a meaningful impact on our climate projections. Katla “emits vast amounts of CO2 — it’s in the top five globally in terms of CO2 emissions from volcanoes,” Dr. Tuffen explains.
“If methane produced under these ice caps has a means of escaping as the ice thins, there is the chance we may see short term increases in the release of methane from ice masses into the future,” says lead author Dr. Rebecca Burns.
However, the team says it’s still unclear such processes will play out in the context of climate change. There could be a short-term spike of methane released while glaciers melt and thin out, but the process may be self-limiting in the long-term: without ice, the conditions for methane production are removed.
The paper “Direct isotopic evidence of biogenic methane production and efflux from beneath a temperate glacier” has been published in the journal Scientific Reports.
A NASA study of certain bubbling lakes in the Arctic suggests that methane deposits are being released due to an understudied phenomenon called ‘abrupt thawing’. Methane — which is 30 times more potent at trapping heat than carbon dioxide — has been frozen for potentially thousands of years and its sudden release could significantly impact the climate by the end of the century.
Methane bubbles up from the thawed permafrost at the bottom of the thermokarst lake through the ice at its surface. Credits: Katey Walter Anthony/ University of Alaska Fairbanks.
Methane and carbon dioxide are both produced in thawing permafrost as animal and plant remains decompose. As long as this organic matter remains frozen, it will stay in the permafrost. However, if it thaws, it starts decaying, releasing carbon dioxide or methane into the atmosphere — which is why scientists are deeply concerned with the present development.
Right now, Earth’s atmosphere contains roughly 850 gigatons of carbon (a gigaton is about the weight of 100,000 school buses). Scientists estimate that there is about twice as much carbon frozen in permafrost than present in the atmosphere today.
That doesn’t mean that all of the carbon will end up in the atmosphere. The trick is to find out how much of the frozen carbon is going to decay, how fast, and where. The full picture seems to be even more complex than previously thought. In a new study, scientists have discovered a new source of methane that hasn’t been accounted for by climate models — methane emissions from ‘thermokarst‘ lakes.
Such lakes form when permafrost taws at a faster rate and deeper levels than usually happens. This sudden thawing creates a depression which fills up with rainwater, ice, and snow melt. The water’s presence then leads to even more thawing at the shores of the lake, speeding up the rate of methane release into the atmosphere.
“The mechanism of abrupt thaw and thermokarst lake formation matters a lot for the permafrost-carbon feedback this century,” said first author Katey Walter Anthony at the University of Alaska, Fairbanks. “We don’t have to wait 200 or 300 years to get these large releases of permafrost carbon. Within my lifetime, my children’s lifetime, it should be ramping up. It’s already happening but it’s not happening at a really fast rate right now, but within a few decades, it should peak.”
Walter Anthony and colleagues used a combination of computer models and field measurements to reach the conclusion that abrupt thawing more than doubles previous estimates of permafrost-derived greenhouse warming.
“Within decades you can get very deep thaw-holes, meters to tens of meters of vertical thaw,” Walter Anthony said. “So you’re flash thawing the permafrost under these lakes. And we have very easily measured ancient greenhouse gases coming out.”
Current models estimate carbon emission from thawing permafrost as a gradual process. These new results suggest that in reality, the Arctic’s thawing feedback loops are more complex than we suspected. It’s all especially concerning considering that the IPCC — the leading international body for the assessment of climate change — did not incorporate any permafrost carbon emissions and the resulting amplification of climate change in its most recent climate projections.
This means that it will be even more challenging to keep global temperatures below the 1.5- or 2- degrees Celsius target set by the international community under the Paris Agreement.
Even so, methane emissions from thawing permafrost pale in comparison to the amount of human fossil fuel emissions. According to the researchers, permafrost methane emissions account for only 1% of the global methane budget. So the best thing we can do is to transition as fast as possible to a carbon-neutral society.
“But by the middle to end of the century the permafrost-carbon feedback should be about equivalent to the second strongest anthropogenic source of greenhouse gases, which is land use change,” Walter Anthony said.
The U.S. oil and gas industry emits roughly 13 million metric tons of methane (a potent greenhouse gas) per year. The figure is 60% higher than that estimated by the Environmental Protection Agency (EPA).
Image via Pixabay.
Most of these emissions didn’t come from the industry’s main activity; rather, it oozed out from leaks, malfunctioning equipment, and other “abnormal” operating conditions. Still, irrespective of their source, these emissions do take a toll on the environment. In 2015, the paper notes, these emissions had roughly the same environmental impact as the carbon dioxide emissions resulted from all of the U.S’ coal-fired plants.
“This study provides the best estimate to date on the climate impact of oil and gas activity in the United States,” said co-author Jeff Peischl, a CIRES scientist working in NOAA’s Chemical Sciences Division in Boulder, Colorado.
“It’s the culmination of 10 years of studies by scientists across the country, many of which were spearheaded by CIRES and NOAA.”
The paper drew on measurements performed at over 400 well pads in six oil and gas production basins and multiple midstream facilities. The measurements were focused around valves, tanks, and other equipment. In addition, the team also drew on aerial surveys covering large areas of the U.S. oil and gas infrastructure.
Methane was the main focus since it’s the principal component in what we commonly refer to as ‘natural gas’. It’s also a very powerful greenhouse gas, having over 80 times the warming impact of CO2 for the first 20 years after release (it breaks down in the atmosphere after that). The study estimates that methane emissions in the U.S. total about 2.3% of total production — which would negate any potential benefit of the U.S. switching from coal to natural gas in the energy sector over the next 20 years.
The total cost of these methane leakages is around $2 billion, according to the Environmental Defense Fund, “America’s most economically literate green campaigners.” That quantity, they add, would be enough to heat 10 million homes in the U.S.
On one hand, the findings raise concerns around our efforts to mitigate climate change — if the U.S. leaks so much methane under our collective noses, how much does the global oil and gas industry leak? On the other hand, it’s an easily fixable problem. Repairing the leaks and addressing other factors that contribute to the methane emissions would be a quick and cheap way to keep a lot of methane out of the atmosphere. However, this is not the first time the U.S. leaks methane — similar findings were reported on in 2016.
The paper “Assessment of methane emissions from the U.S. oil and gas supply chain” has been published in the journal Science.
Titan, one of the least Earth-like places in our solar system, turned out to have surprisingly Earth-like features.
Doom Mons (mountain) and Sotra Patera (depression), two remarkable features on the surface of Titan. Topography has been vertically exaggerated by a factor of 10 for visibility. The false color shows different surface material compositions as detected by Cassini’s visual and infrared mapping spectrometer. Image credits: NASA/JPL.
Until recently, not much was known about Saturn’s moon Titan. But the Cassini-Huygens mission changed all that. Titan, a Mercury-sized world with a surface shrouded in a thick, nitrogen-rich atmosphere, was found to be the only place other than Earth where clear evidence of stable bodies of surface liquid has been found.
Titan is also a prime candidate for finding extraterrestrial life, which is why researchers have been trying to better understand its structure. Now, in two published papers, astronomers present the first proper map of Titan, revealing its features in unprecedented detail.
It took doctoral student Paul Corlies a year to assemble the map from all existing data. It was no easy feat since only 9 percent of Titan’s topography has been observed in relatively high-resolution. Another 25-30 percent of the topography imaged in lower resolution. The rest was created using an interpolation algorithm — which means we don’t really know how the rest of Titan is like, but we know how it probably looks like.
Cassini’s radar mapper has obtained stereo views of Titan’s surface during 19 flybys over the last five years. Image credit: NASA/JPL/USGS.
For starters, the map reveals Titan to be a bit flatter (more oblate) than previously thought. This suggests that the thickness of Titan’s crust also varies more than expected. Corlies also reports that the surface of Titan is covered by mountains, though none of them are higher than 700 meters (2300 feet). The map also shows Titan’s lows, allowing scientists to confirm that two locations in the equatorial region are in fact depressions — and not dried seas, as another theory proposed.
Researchers also analyzed Titan’s impressive lakes, but don’t get your hopes up just yet. As opposed to Earth’s lakes, which are covered by water, Titan’s lakes are filled with liquid methane, a hydrocarbon.
Starting from sea level
Corlies found that Titan’s three most massive lakes (or seas) share a common equipotential surface — which is just a fancy way of saying that they have a common sea level. Titan’s lakes communicate with each other through the subsurface; the lakes that are dry are all at higher elevations than the filled lakes in their vicinity. Alex Hayes, assistant professor of astronomy and also an author, predicted this in his previous models of Titan.
“We don’t see any empty lakes that are below the local filled lakes because, if they did go below that level, they would be filled themselves. This suggests that there’s flow in the subsurface and that they are communicating with each other,” said Hayes. “It’s also telling us that there is liquid hydrocarbon stored on the subsurface of Titan.”
The fact that astronomers are understanding so much about a satellite so far away from Earth is truly astounding, yet this is only a stepping stone for other research. Study authors say that the map will help others working on Titan’s geology and morphology, as well as those trying to improve models for extraterrestrial bodies. Ultimately, it could even help scientists understand whether or not life exists on Titan.
“We’re measuring the elevation of a liquid surface on another body 10 astronomical units away from the sun to an accuracy of roughly 40 centimeters. Because we have such amazing accuracy we were able to see that between these two seas the elevation varied smoothly about 11 meters, relative to the center of mass of Titan, consistent with the expected change in the gravitational potential. We are measuring Titan’s geoid. This is the shape that the surface would take under the influence of gravity and rotation alone, which is the same shape that dominates Earth’s oceans,” said Hayes.
P. Corlies, et al. Titan’s Topography and Shape at the End of the Cassini Mission. Geophysical Research Letters, 2017; 44 (23): 11,754 DOI: 10.1002/2017GL075518
A. G. Hayes, et al . Topographic Constraints on the Evolution and Connectivity of Titan’s Lacustrine Basins. Geophysical Research Letters, 2017; 44 (23): 11,745 DOI: 10.1002/2017GL075468